CHAP. I. Of the Elements and chief Accidents of Ʋrine.

WHEN the Liquor of the Urine, being either fresh rendred from the body, or putrified by a long digestion, is exposed to a spagirick Analysis, it is wont to be resolved into these parts or principles: In the Distilling, first, ascends whatever of a vi­nous spirit is in it, diluted with water; but yet in so very small quantity, that it is not easily to be perceived by the taste it self. To this follows a watry liquor, large enough in proportion, with which are mixed some more loose particles of Salt, and Sulphur especially. Thirdly, There is stilled forth a very penetrative water; which is commonly called the spirit of Urine, but in truth almost without any vinous spirit, and is chiefly phlegm highly sharpned with Salt, and therefore it ascends last, as in the distillation of Vinegar: but forasmuch as the salt of Urine is volatile, but that of Vinegar only in the Flux; therefore the liquor stilled forth, which is greatly impregnated with its particles, is very acid: That which is imbued with the saline Particles of the other, is exceeding sharp and pricking. It is a sign that this kind of Spirit of Urine (as it is commonly known) ows its sharp­ness chiefly to the Salt; because, though it be most subtil it will not take fire, but being put to it extinguishes it. After the humidity is wholly exhal'd, another porti­on of Salt remains with the earth, in the bottom of the cucurbit; to which if a more hot fire be made, that Salt will be sublimed into the Alembick, and the earthy feces only remain. This kind of Anatomy of Urine plainly shows, that the Elements of which its liquor is composed, are a great deal of Water and Salt, and a little of Sul­phur and Earth, and a very little of Spirit.

The saltness in Urines is perceived by the taste and touch; it comes nearest to a Nitrous salt in savour: It is drawn indeed from saline particles of things eaten, which being more plentifully exalted by the concoction in the Bowels, and the circulation in the Vessels, for the most part go into a volatile Salt. That is truly Salt and Spirit, by reason of the long accompanying of either together, are gathered into a most strict bond; and therefore it happens, that the Salt it self otherways fixed, is carry­ed up on high, and rendred able for motion, as it were by the wings of the other. Urines contain in them more or less of Salt, according to the disposition of our body, and have it either more volatile or fixed; which are therefore of a divers colour and consistency.

That there is Sulphur contained in Urines, their quickly putrifying, and stink, sufficiently testifie: it arises from the fat and sulphureous particles of Meats, in the concoction being most minutely broken, and boyl'd with the serum and salt; so as also there is less plenty of Spirit in it, than is in Blood, Soot, or the Horns of Ani­mals: wherefore in the distillation of Urine, there ascends nothing almost of an oylie form or fat. But indeed, whilst the blood is circulated in the Vessels, the spiri­tuous and sulphureous little bodies, which fall away from it, do for the most part evaporate out of dores; in the mean time, the saline recrements, and the watery, chiefly constitute the Piss: nevertheless, Urines do always participate a little of sul­phur, but its quantity and proportion, is diversly altered according to the various degrees of Concoction and Crudity; and thence also the colour and consistence re­ceive many mutations in Urines.

That there is but a very little of vinous spirit in Urines, the defect of it in the liquor first distilled forth, also the soon putrifying of the Stale do testifie: but that there is some, the intestine motion of the particles in the Urine, doth argue, to wit, the departure of the thin from the thick, and the spontaneous separation of some parts from others, and a collection of them into a settlement: besides, the sa­line particles (for that they are made volatile) are married to spirituals, and so they are of a more ready motion, and energy; yet according to the divers plenty of spirits in Urines, and their power, there arise divers manners of hypostases and settle­ments; also the Urines themselves, sooner or slower putrifie.

The watry part of the Urine far exceeds the rest in quantity, and is greater than they by almost a sixth part: it is not so simply drawn forth by distillation, but that some particles of Salt and Sulphur (for as much as they are volatile) ascend with it, and impart to the water an ingrateful stink: the potulent matter, copiously taken with aliments, affords an original to this; which of what kind soever it be, before it is changed into Urine, lays aside its proper qualities, and acquires others; for tru­ly, from the assumed liquor, there is nothing sincere almost left in the Piss, besides meer humidity.

That there is earth, and muddy feces to be had in Urines, its distillation, or eva­poration sufficiently declares: for when the rest of the parts are exhaled, the earth as it were a caput mortuum, will remain in a moderate quantity in the bottom: Foras­much as in the nourishing juice, there is required something solid besides the active principles of salt, sulphur, and spirit, whence the bulk and magnitude of the body grows; the recrements of this, viz. the earthy seculencies, are plentifully dissolved in the serum, and contribute to it a thick consistence and contents: but these shew themselves after a divers manner, according to the state of Concoction and Crudity.

These are the principles which constitute the body of the Urine, also into which it is easily resolved, by a Chymical Analysis: Out of the divers changes, and various contemperation of these, the other accidents of Urine arise, viz. Quantity, Colour, Consistency, and Contents, which are as to the sense the most notable concerning it, and the chief objects of the rendred Urine: For when there is nothing almost be­held besides in the Piss, they constitute these first Phaenomena, in which rightly sol­ved, consists the whole Hypothesis of this Science: Wherefore we shall speak in the next place concerning these, and first of the Urine of healthful people, what its quan­tity may be, how coloured, with what consistence and contents indued; and toge­ther shall be unfolded, out of what mixture of Elements, and by what Concoction in the Viscera, and Vessels, each of these depend. Secondly, shall be shown how many ways the Urines of Sick people vary from the square or Rule of this of the Sound: and I shall endeavour to assign, for the several differences of them, proper Causes of their alterations; and these shall conclude our first proposition in this Discourse, viz. the Anatomy of Urine.

CHAP. II. Of the Quantity and Colour of the Urines of Sound People.

THE Quantity of the Urine in found people ought to be a little less than the humor, or liquid substance daily taken; for moist and drinkable things dayly taken, are the matter it self of which Urines are first made: But these (hunger and thirst urging) are more plentifully required, both that they may suffi­ciently wash the mass of the Chyme, by which means it may rightly ferment in the Viscera; and that they may serve for a Vehicle, both to the Chyme, whereby it may be conveyed to the bloody Mass, and to the Blood it self, that it might be circu­lated in the Vessels without thickening; and to the Nervous Juice, whereby it might actuate and water the Organs of sense and motion: when the serous Latex by this means hath bestowed whatever it hath almost of Spirit and Sulphur, for nourish­ment, Heat, and Motion, it gives way to a new nutritious humour; and it self as unprofitable, being secluded from the Blood, by the help of the Reins is sent away. [Page 3]The nourishing liquor, which will at last be changed into Urine, of its own nature is divers, viz. now watry, now impregnated with Spirit, now with Salt and Sulphur, and according to the various forces of this or that Element in it Urines are wont to be somewhat altered: However all liquors taken in at the mouth, do not pass thorow our body whole and untouched; but that they undergo mutations in various parts, and lose a little portion of their quantity, before they are made into Urine: For the Latex or Humour to be converted into Urine, is first of all received into the Ven­tricle, (for I assent not to Reusner, who affirms the same falling for the most part on the Lungs, to cause the more quick making water after drinking) whilst that it stays in the Ventricle, it is there boyled; also impregnated with Salt and Sulphur of its own, or from more solid Aliments dissolved: then very much of it is confused in the blood, with the nourishable juice; which, when it is a long time Circulated, from thence receives a farther tincture of Salt and Sulphur, according to the various temper of the Blood, and its inkindling in the Heart: Hence some portion of it is derived with the Animal Spirit, to the Brain and nervous stock; and afterwards from thence, being made lifeless and weak, is lastly reduced into the bosom of the Blood; after that it hath bestowed on the Blood and Nervous Juice, whatever of ge­nerous or noble is conteined in the Serum, also no small quantity is consumed by sweat and the other emunctories; what remains, whilst that the Blood continually washes the Reins, a precipitation being made, either by a straining or force of a certain ferment, it is there separated from the Blood, and from thence passes thorow the Ureters into the Bladder, and so is carryed forth of doors.

From the origine and lustration of the Serous Latex, but now described, it plainly appears, that the Urine ought to answer to the quantity of the liquids taken, in somewhat a lesser proportion, perhaps under a third part; which plainly shews the disposition and strength of the Viscera serving for Concoction, as also the temper and distribution of the Blood it self, and after a sort of the nervous juice; moreover it carries with it signs of the affections of the Urinary passages. The quantity of the Urine declines often from this Rule, so that sometimes it superabounds, also some­times is deficient: and either for a short time, may consist with a disposition not much unhealthful; but if these kind of distempers continue long, they argue a sickly condition. Concerning these we shall speak among the appearances of the Urine in a diseased condition of the Body; we shall now next consider the colour of a sound Urine.

The Urine of Sound People, which is rendred after Concoction is finished in the Body, is of a Citron colour, like Lye a little boyled: which without doubt proceeds from the Salt and Sulphur of the nutritious juice, and the Blood, dissolved in the Concoction, and boyled in the Serum. This colour doth not arise only from Salt (as some would have it) because the Liquor impregnated with Salt, unless it be evapora­ted to a certain thickness, will not grow yellowish: Also Salt of Tartar, being dis­solved by melting, continues still clear. What may be objected concerning the Lye of Ashes, I say, there the whole Sulphur is not consumed by burning, but the Citron colour arises from some saline Particles, and others Sulphureous burnt, and sticking together in the Ashes, and then infused or boyled in the liquor. Neither doth the Urine of sound people acquire this same colour from Sulphur only, because Sulphur in a watry Menstruum, is not dissolved unless by the addition of Salt, nor will it give any tincture of it self; but if Salt of Tartar and common Sulphur be digested together in water, or if Antimony be boyled in a saline Menstruum, both liquors will by that means grow yellow like Urine; after the like manner, the saline and sul­phureous Particles of Aliments, being incocted and most minutely broken in the Se­rum, by a Digestion in the Ventricle and Intestines, and by a Circulation with the Blood in the Arteries and Veins, impart to it a Citron Colour.

This kind of dissolution of Salt and Sulphur, by whose means the Urines are made of a Citron Colour, is first begun in the Bowels; and afterwards perfected in the Vessels, and very much depends upon the Concoction performed in the Ventricle and the Intestines: For here, by the help of heat and of ferments, the Aliments taken are chiefly subdued; the bond of mixture being broken, the saline and sul­phureous Particles being most smally broken, and made small, go into a milkie Cream, and from thence the Serum remaining after that Concoction and distribution of that milkie juice, becomes of a Citron colour: after the same manner, as when the Salt of Tartar and common Sulphur being dissolved together, and mixed with some acid [Page 4]thing, indue a milkie colour; then the contents being separated by setling, the re­maining liquor grows yellow like Lye. If that the aliments, by reason of an evil disposition of the Ventricle, are not rightly digested in the first Concoction, as in the Longing Disease or Pica, the Dropsie, and other ill dispositions of the Bowels, usually comes to pass, the Urine also is rendred crude, clear, and almost insipid, like Fountain water; but if by reason of the ferments of the Viscera being more than duly exalted, or otherways depraved as in the Scurvy, Hypochondriac distemper, or Feavourish intemperance, the particles of things eaten are too much dissolved in the first Region, by that means Urines are rendred red, and thick.

The Serum, as hath but now been said, being imbued with a lixivial tincture in the first Concoction, and confused in the Blood, so long as it is circulated with it, it is yet further Concocted, and acquires a more deep colour; for the particles of the Blood being roasted and scorched, although for the most part they are laid aside into the Gall bag, yet being in a manner boyled in the Serous Latex, they heigh­ten its colour; hence the Concoction being ended, the Urine which is first made, is more Pale, and that which is last, more Red. That which is made after long fasting, is yet more high Coloured. Where the Blood is more cold, as in Cachectical people, the colour of the Urine is made less; where the Blood grows raging with a feavourish Heat, and is roasted, the Urine grows highly Red.

Concerning the Urines of sound people, it is worth observation, that which is made after plentiful Drinking, hath no tincture, but is pale like water; of which we shall enquire, by what means the Serous Latex so suddenly slides away out of the Ventricle, (contrary to what is vulgarly believed) and passing thorow all the Chyli­ferous passages, then the Veins, Arteries, the bosom of the Heart it self, and the turnings and windings of the Veins, and Ureters, is put forth of the Body within so short a space: moreover, how it comes that the Urine being so precipitately made, contrary to most other things, is not only changed into no Colour in its passage, but it also loses its own proper: For as the Proverb is, Our Drink goes thick in, and comes forth thin: or We Drink thick Beer, and Piss clear.

Concerning this we say, that besides the long wandring of the nourishing juice, to wit, whereby, after some stay in the Ventricle, it slides into the Intestines, and from thence thorow the milkie Vessels into new passages, and thence is carried into the Veins, (which carrying about cannot be quickly performed) it is most likely, that there is another nearer passage of the same Nutritious Juce, whereby indeed it may be conveyed immediately and without delay to the Mass of Blood, and perhaps to the nervous Liquor; and therefore, after fasting there immediately follows a most quick refection of strength and spirits, after Eating, and especially after Drinking; which indeed cannot be thought to be made by the Spirits and Vapours; also from such drinking, the Urine is presently rendred, and indeed sooner than it can be thought, that the Mass of the Chyle can be sent out of the bosom of the Ventricle; wherefore, it is not improbable, that when the Alimentous Liquor is entred the Ventricle, pre­sently the more thin portion of it, which consists chiefly of Spirit and Water, is im­bibed by its Spongeous Membranes; and from thence being instilled into the little mouths of the Veins, it is presently confounded with the Blood, flowing back to­wards the Heart. For of this opinion (though not very stubbornly) I always was, That the Chyme was in some measure immediately derived from the Ventricle, and Intestines, by the branches of the Vena Porta, into the Mass of Blood; and as the mil­kie passages carry it about by a long compass, whereby it may be instilled into the de­scending Trunk of the Vena cava; so that it may be carried in a more near way, viz. into the ascending Trunk of the same, by these Vessels; forasmuch as the Blood be­ing made poorer in its Circulation, returning from either part, before it had entred the Heart, it ought to be refreshed with a new juice, whereby it might more lively ferment in the bosom of the Heart; but forasmuch as the much greater part of the Blood is carryed upwards, surely it may seem agreeable to truth, that at least some portion of the nourishing Juice may be added to this, as it were a sustenance, it be­ing before burnt forth, and almost lifeless, for its new inkindling in the Heart. The Arguments that seem to perswade to this, not of light moment, I could here heap together, but I should so divert far from our proposition: wherefore, that we so suddenly make a waterish Urine after Drinking, I esteem to be done after a man­ner as was but now said; therefore the Liquor that is carryed so hastily from the Aliments to the Mass of Blood, passing thorow the so narrow windings (as are the [Page 5]Membranes of the Viscera) being drawn as it were by distillation, the more thick matter being rejected, consists almost only of Water and Spirit; with which indeed it refreshes the vital Spirits, and dilutes the Blood; about which task, when the spi­rituous part is consumed, the watry Latex, because of its plenty, being heavy and troublesome, is continually sent away by the Reins; and when it comes from the Ven­tricle, not yet imbued with Salt and Sulphur, nor is long circulated with the Blood, that it might by that means acquire a lixivial tincture, it is rendred thin, and clear.

CHAP. III. Of the Consistence and Contents of the Urine of Sound People.

SO much for the Quantity and colour of Urines, which proceed from a sound Body; but as to what belongs to the Contents, we must know, that there ought to be nothing besides the Hypostasis in a sound Urine; but what this is, and by what means it sinks down, remains to be unfolded in the next place.

So long as the Mass of Blood, being fused with the serous and nourishable humour, is continually Circulated in the Vessels, from it a certain nutritious juice is made, by a perpetual digestion, which being put continually to the solid parts, goes into nourishment: This first of all is digested into a glutinous humour, like the white of an Egg, afterwards into thin Filaments or Rags, which being interwoven in the Pores and little spaces of the solid parts, still afford to them an increase of new sub­stance; but whilst the Serum being mixed with the Blood, washes all the Regions of the Body, it sucks up into it self a certain superfluous portion of this last Aliment, to be lay'd on the solid parts, and carries it forth of dores with it self; and this it is that constitutes the Hypostasis or settlement in Urines; wherefore so long as this is pre­sent, it indicates how far Concoction and Nutrition in some measure is performed, and is accounted a laudable sign; its absence shews Crudity and Cachectical people, or a Dyscrasie in Feavours; it consisting of small Threads or Filaments, is dispersed at first thorow the whole body of the Urine, and then is collected into a little Cloud, by this means. These Filaments or Threads, are long, and smooth, also indued with some sharpnesses like Brier-pricks, that from thence being shaken about, they easily lay hold of one another, and are fastned together; even as if into an Urinal full of water, you should cast many Hairs, and then by shaking about the Vessel, the hairs at first swimming dispersedly, in a little time would lay hold on one another, and be col­lected into a little bundle; after the same manner (as it seems) the little threads which constitute the Hypostasis or settlement being variously here and there agitated by the colour and spirits implanted in the Urine, intangle and thrust upon one another, un­till they gather into one little Cloud by the mutual knitting of all together; and be­cause these Filaments are compacted, and more solid than the other Contents of the Urine, they sink towards the bottom with their weight.

It is very likely, that these kind of Filaments, make the Hypostasis in the Urines of Sound people, for that the Blood being well constituted, and disposed to nourish­ment, is very much stuffed with Fibres, or white Filaments: because, when a Vein is opened, if the Blood let out be received into warm water, it will be conspi­cuous to any one; for the red thick substance being diluted with the liquor, these smooth and white threads swim in the water; wherefore it seems, that some of these thin or slender rags, being snatch'd away with the serous juce, are the matter of this cloud subsiding in the Urine; wherefore in Cachectical people, by reason of Cru­dity, the Blood being very waterish, and unfit for nourishment, is destitute of these well labour'd Fibrils; also in Dyscrasies, when the nutritious humour, the Blood being too much scorched, is not rightly concocted into these kind of Filaments, the Hypostasis in Urines is either wholly wanting, or is very confused and disturbed.

It is said to be a good and laudable Hypostasis, which is of a whitish colour, of a round and equal figure, and sinks towards the bottom, to which are required, First, that that last Aliment be rightly labour'd, whereby the Filaments may become white, smooth, and solid, like to slender Fibres. Secondly, that the Urine be sufficiently strong in spirits, which (as is beheld in the growing hot of Must, or new Wine) [Page 6]may agitate, and compel here and there all parts. Thirdly, that the liquor be not too thick, nor that its Pores be first possessed by strange bodies, whereby the motion of the contents may be hindred, but that a sufficient space may be lest, for the free agitating and tossing about these kind of Particles.

If the substance be red, it is a sign that that last Aliment is scorched and burnt, with too much heat; wherefore such a sediment, for the most part is in the beginning of a Feavour, so long as the Coction in the Viscera and Vessels, is not wholly perverted; if the Hypostasis be broken and unequal, it is a sign that the nutriment destinated for the solid parts, is not rightly and equally concocted, and that its Particles are not homogene, and alike in every part: wherefore the Filaments do not cohere together, but these with those, and they with others, are entangled apart; hence some more thick descend towards the bottom, and others more light swim upon the top. When the Hypostasis does not wholly sink down, but hangs all of it, either in the middle or upper Region, that happens, because that those Filaments are not per­fectly laboured, nor solid and compact, but more rare and spungy, or because the liquor is thicker, and more impregnate with Salt and Sulphur, and therefore like Lie it sustains some weights, which otherwise would sink to the bottom. Sometimes the Hypostasis is wholly wanting, in sound people, after long fasting, immoderate labours, or copious sweating, the matter being wholly consumed into nutriment, or evaporated by sweat; in Feavours, by reason of the very depraved condition of the Blood; also in the Pica, Cachexie, and other Distempers of that kind, by reason of the great Crudity.

Concerning the consistency of the Urine in sound people, there is not much wor­thy consideration to be met with: It is wont to be of that sort, as midling Beer is, being purified by a long Fermentation; or Lye a little boyled, viz. the watry liquor of the Urine, ought to include in its Pores and passages, a great many Particles of Salt, and Sulphur, most smally broken, and dissolved; and besides a little of earth, divided very exceeding small, and dispersed thorow the whole body of the Piss; if the consistence be thinner than it ought, as it is in clear, or limpid Urines, and watry, it is a sign of indigestion and crudity; that the Aliments are not fully overcome, and Concocted; but if the Urine be thicker, and closer than it ought, it is a sign, that the body of the liquor, is filled with preternatural Contents. But of these elsewhere, when we shall speak of the Urines of the Sick.

Thus far of Urine, forasmuch as it is an Excrement, and sign of Concoction in a sound body (truly performed in the Viscera and in the Vessels) the quantity or bulk of which is to be determined by the potulent matter; the colour Citron, from the dissolved Salt and Sulphur, and boyled in the Serum; the Hypostasis or Contents depend upon the Filaments, elaboured in the Blood, for the nourishment of the solid parts; the consistency on the Salt and Sulphur, together with the Particles of Earth, filling the Pores and passages of the serous liquor. It next remains, that we treat of the Urines of sick people: in which also, the Quantity, Colour, Contents, Con­sistence, and some accidents besides, offer themselves to consideration.

CHAP. IV. Of the Quantity and Colour in Urines of sick People.

IN a Morbous provision of Bodies, or Sickly estate, the quantity of the Urine does not exactly quadrate with the proportion of the liquid things taken; for sometimes it wants of its due measure, and sometimes exceeds it. When the Urine is much less than the drinkable things taken, the reason is, because the watry Latex either stays somewhere in the Body, or is diverted by some other way of Ex­cretion, than by Urine: if it remains within; First, it is either heaped up about the Viscera, and their Cavities, and so is stay'd now in the Ventricle, more than it ought to do, and induces by the distention of it, troubles, with spitting; but more often, it is laid up in the hollowness of the Abdomen, and sometimes of the Thorax and head, and there is wont to cause Hydropic Diseases. Or, Secondly, the Serum stagnates in the Vessels, and so increases the bulk of the Blood, and Nervous Liquor, [Page 7]and notably perverts its motion; whence Catarrhs, Rheumatick distempers, and often Palsies and Convulsions are caused. Or thirdly, this watry humour is fixed in the habit of the body, and so creates a swelling up of the whole body, or of some parts. Or fourthly and lastly, it is obstructed in the urinary passages, by the Stone, or thick matter, as it were a dam opposing it; and causes in those parts pains and Convulsions, and a fulness of the Serum in the whole body. When the serous water is other ways bestowed, the Patients are for the most part prone to frequent and troublesom Sweats, or almost to a continual Loosness.

The distempers therefore which the small quantity of the Urine is wont to indicate, are sometimes the swelling up of some of the Viscera, and a heaping up of water in them, sometimes Catarrhal distempers, sometimes evil dispositions of the nervous stock: sometimes an Anasarca and watry Tumors; and sometimes the stony disposition of the Reins and Bladder. And sometimes also the diminution of the Ʋrine is the effect and sign of some other preternatural evacution, viz. an immoderate excretion of Sweat, Lask, or some other thing. To describe here exactly all the subsistences of the serous Latex, either in the body, or the causes of it other ways excreted, and the manner of doing it, were to transfer hither almost the whole matter of Pathology; for many and divers are the occasions and circumstances, whereupon this Serum is heaped up in this or that part, and subsisting in the body, diminishes the quantity of the Urine; but for the most part the principal and most frequent cause of this consists not so much in the fault of the Liver, Spleen, or Reins, as of the blood it self: to wit, a copious and free making of Urine, as also its stay in the body, and only made in little quantity, depend chiefly on the temper of the blood, and either on its kindling, or fermentation in the heart: for if the blood be strong in rightly exalted principles, (viz. Spirit, Sulphur, and Salt) it grows very hot in the Vessels, and so the frame of the liquor being loose enough, it is duly kindled by the ferment of the heart; and almost spiritualizes the whole, passes through all parts with heat and a rapid motion, without stopping, and whatsoever is superfluous and volatile, evaporates out of doors: and whilst the blood is rarified, and boiling with heat, passes through the Reins, what is serous is easily separated, either by the strainer of the Reins only, or (which is most likely) by a coagulation, and is as it were precipitated from the remaining mass of the blood. The same thing al­most happens after this manner to the blood, as we may observe in Milk, viz. whilst it is warmed, and grows hot, it most easily goes into parts, and its Serum is most easily separated by the least drop of Runnet, or Coagulum put into it: but if you pour much more strong and sour ferment into it, when it is cold, a precipitation will hardly follow; so if the blood becomes through an evil constitution, or ill man­ner of living, more cool and watry, that being less endued with active Elements, it grows but dully hot, and is but little kindled in the heart; it is circulated very slow­ly and difficultly in the Vessels; passing through the Pores and passages of the Viscera, it cleaves a little to them, and leaves something behind it; whence are begotten every where Obstructions and Tumors; also the blood by this means becoming viscous and cool, and so unfit for precipitation or percolation, lays aside less readily its excrements in the Reins; but leaves them every where in the body, because it hardly, and not without the residence of a certain humor, is circulated. Wherefore in this state, those things that move the blood very much, as exercise and a more quick motion; or also such as may fuse it, as it were with a Coagulum or Runnet, as are sharp things, and preparations of Salts, will more freely provoke Urine.

It sometimes happens, that the Urines of the sick are made in a large quantity, and very profuse, that in a day and a nights space, they make perhaps twice or thrice as much water, as the Liquids they have taken; the causes of which distemper are also various, and the significations very divers; if after the suppression of Urine, or its quantity formerly lessened, if in Hydropick distempers, Rheumatisms, or passions of the nervous stock, or in the Crises of Feavers, a flowing down of the Urine follows, either of its own accord, or by the use of Diureticks, it denotes a Cure of the disease, or preternatural disposition, or at least a declining of it. But if (as I have often observed) in a lean and weak constitution (without any of the previous distempers but now recited) the Urine exceeds much the Liquids taken, and from thence a great debility of the whole follows; this indeed signifies an evil disposition, with a tendency to a wasting or Consumption. I have known some women of a tender and most fine make, who sometimes being ill, for many days, [Page 8]were wont daily to make water in a great abundance, (exceeding twice the Liquids taken) and that watry and thin, without contents or settlement; at which time they have complained of a languishing of strength, difficult respiration, and an im­potency to motion. I suppose in this case, that the blood and nervous juyce grow too sour, from the salt carried forth, and suffering a Flux, and therefore that they are somewhat loosned in their mixture, and fused so much into serosity, as to be made fit for it. For it is to be observed, that all Liquids, though more thick and mucilaginous, if they be kept to a sourness, presently become for the most part wa­try and limpid: also the flowing down of the Urine is sometimes seen to arise from such a disposition of the blood and humors: for that the Urine so copiously excreted, is like Vinegar in taste; and these kind of distempers are usually cureed, chiefly by Chalybeates, and not by binding and thickning things.

But as to what respects the Colour, the Urine of sound people may be the square or rule, to which all the rest of the sick may be referred; for as the colour of sound peoples is Citron, the Urine of the sick is paler than Citron, and so either watry, or white, or higher coloured than it; whose chief kinds are, flame-colour, yellow, red, green, and black. I shall run through every one of these briefly, and endeavour to weigh them together, by what causes all the alterations may be made, and what distempers, or provisions of diseases they are wont to make known.

The Urine is watry or limpid, when by reason of the indigestion of the Ventricle, the saline and sulphureous particles of things eaten, are not rightly subjugated, nor being smally broken, are made so volatile, that being dissolved in the Serum, they may impart to it a tincture, which it may carry with it, through the several turnings and windings of its passage: For the Latex or juyce to be changed into Urine, because it is forced through very secret passages, and narrow, as it were by a certain distil­lation; therefore it is wholly deprived of the colour and consistency, which it had from the taken Liquids, and imbibes almost nothing, but the volatile part, from the Chyme, whose Vehicle it is. Wherefore, if by reason of the great crudity, the Salt, Sulphur, and other contents are not first made volatile in the Viscera, nor afterwards dissolved in the Vessels, that they may make their passage together with the serous juyce; it being at last stripped almost of all, is sent out like clear water. That such Urines do want the active principles, it is a sign, because they are kept a long time from putrefaction: This sort of Urine denotes in Virgins, for the most part, the Green-sickness, in most the Cachexy or Dropsie; in all it is a note of in­digestion and crudity. Sometimes in those obnoxious to the Stone, it foretels the approach of the fit, viz. whilst the Serum is coagulated by the stony juyce in the Reins, its dissolutions and contents are congealed into a tartareous matter, only a watry juyce or Latex staying behind. Those who for some time make a thin and watry Urine, whatever sickness they are obnoxious to, have often adjoyned to it a difficulty of breathing, and shortness thereof after motion, and a distention about the region of the Ventricle, and as it were a swelling up after eating. The reason of the former wholly depends on the defect of spirits in the blood, because its liquor is not fully imbued with active principles (of Spirit, Sulphur, and Salt) rightly ex­alted; therefore it is not sufficiently kindled by the ferment of the heart, whereby the whole may presently leap forth, and break as it were into a flame: but that hardly fermenting, and being apt to stagnate in the heart, and for the most part to reside there, burdens it grievously: wherefore if the blood so disposed, is urged more than it is wont, by a more quick motion, into the bosom of the Heart, because not being rarified of its own accord, it may presently go wholly forth, therefore there is need of great endeavour of the Lungs, and a more quick or frequent agitation, whereby it may be carried forth. Therefore watry Urines signifie this kind of Cru­dity in the blood; because, for as much as they receive no tincture almost from the Salt and Sulphur, it is a sign that the Particles are little dissolved in the mass of blood, or are rendred volatile. As to what appertains to the inflation of the Ventricle (of which also limpid or clear Urines are the effect and sign) I say, because of a defect of due Fermentation, the Chyle goes not into a volatile Cream, but (like bread not fermented) into a sad and heavy mass; which indeed is slowly, and not without a residence of viscous Phlegm, carried out of the stomach: its reliques being impacted in the folds and Membranes of the Ventricle, obstruct all the Pores and passages, that nothing may vapour forth, nor that the thin and spirituous part may be conveyed (as it ought to be) by the secret passages, to the blood: hence flatulencies are be­gotten, [Page 9]which continually distend the Ventricle, and blow it up beyond its due bulk: also when those Feculencies are left a long time in the stomach, they abound in a fixed Salt, and degenerate now into an acid, now into a vitriolick matter, or of some other nature; from whence Heart-aches, desire of absurd things, oftentimes Heat with cruel thirst, and sometimes Vomiting arise: some of which though they argue a very sharp heat to lye hid within, yet by reason of the want of concoction, such distempers often render the Urine crude and watry. We have treated thus largely of a limpid or clear Urine, because from hence the reasons of the rest (which as to colour and consistency are pale and thin in healthful persons) may be drawn. For from the Salt and Sulphur, more or less dissolved and boiled in the Serum, the appearances of a pale and straw-coloured Urine, and of other colours, under a Citron colour, are excited; and by the like means, which was said of the watry, they may be unfolded.

There remains another certain kind of Urine, more pale than the Citron colour, not thin, but thick and cloudy, and of a whitish colour; it appears by common ob­servation, that children do often make such water, when they are troubled with the Worms: The reason of which seems, because the matter whereof the worms are made, is a certain viscous Phlegm, heaped up in the Viscera, by reason of the in­digestion of the Chyle, and a defect of making or generating Spirits, which matter at first transmits no tincture to the Urine, because of its fixity, the same afterwards putrifying is exalted, and is in some manner volatilized; and then partly by heat and spirit, is formed into worms, and partly being confused with the passing Chyle, and carried into the vessels, when 'tis made unfit for nourishment, it is separated with the Serum from the blood, and being mixed with the Urine, gives it that white co­lour. Sometimes also in Feavers, especially of children, the Urine is whitish: the rea­son of which is, because the supplement of the nutritious juyce being poured from the Chyle to the mass of blood, is not rightly assimilated, but degenerates into an ex­crementitious humor: A portion of which being incocted in the Serum, imparts to it the thick consistence and milky colour: otherwise than in the Feavers of those of riper years, where when the heat is stronger, the same degenerate juyce impresses on the Serum a red colour. Also the Urine is whitish in the flowing of the Whites, the Gonorrhoea, Ulcers of the Reins and Bladder, and of the urinary passages, by reason of the confusion or mingling of the filthy matter, or the corrupted seed: how­ever it be, that the colour of the urine be white, it is produced from its contents, which at last putting down its settlement to the bottom, the liquor for the most part becomes of a palish and yellowish colour; even as it may be perceived by the making of the Milk of Sulphur, where the milky substance sinking down to the bottom, the over swimming liquor is of a Citron colour.

Urines whose colour is deeper than Citron, owe their appearance, not only to the Salt and Sulphur dissolved more than usual, but in some sort to the more thick contents in the liquor. The more plentiful dissolution of the Salt and the Sulphur, is chiefly performed in the vessels, in the mass it self of the blood, and from thence the Tincture is impressed on the serous Juyce: But this happens to be done for the most part, after a double manner, viz. either by reason of the feaverish fervour, for as much as the blood boiling in the vessels, and being more kindled in the Heart, is very much loosned in its mixture, and so copiously fixes on the Serum the parti­cles of Salt and Sulphur, wasted as it were by the boiling: Or without a Feaver, when these kind of sulphureous and saline little bodies, wont to be sent forth at other sinks, are restrained; and so being by degrees heaped up in the blood, are poured into the Serum. Of this also there are two chief causes or means; for ei­ther the excrements of the blood, which chiefly participate of adust Sulphur, and that ought to be sent away by Choler-carrying vessels, are retained, and so they impress, being suffused on the serous humor, a tincture of yellowness: or else the Effluvia's, which are chiefly of a saline nature, and ought to be evaporated by insen­sible transpiration, are restrained, and from those the urine is filled with a lixivial tincture. The urines of the former kind are proper to people that have the Jaun­dice; but those of this latter are familiar to the Scurvy: for in the Scurvy the saline particles of the blood depart from volatilization, and get a Flux: wherefore, by reason of their fixity, they will not evaporate, and so being more fully heaped to­gether in the blood, they more and more pervert its Crasis, and very much im­pregnate the serous humor with a saltness. The contents which heighten the colour [Page 10]of the urine, are of a twofold kind, to wit, either adust recrements, remaining after the deflagration of the blood, or particles of the nutritious juyce, degenerated into an extraneous matter: Concerning which we shall speak hereafter in their proper place. It now remains that we describe particularly the several Colours of Urine more intense or deep than Citron colour.

1. The first is a flame-coloured urine, which shines with a brightness like the Spirit of Nitre: and this is very often seen in an intermitting Tertian Feaver; this colour arises from a portion of the thinner yellow Bile, mixed with the Serum, whilst it is in motion: for that in this Feaver there is a sharp and hot intemperature of the blood, which burns and scorches all the humors, and so plentifully begets Choler. But al­though this, for the most part, is separated from the mass of blood by the bilary vessels and passages; yet when it abounds in the vessels, a part of it, or (which is the same thing) some burnt and adust particles of the blood and humors being boiled in the serous water, impart to it an high or deep yellowness. This urine is thin and shining, for that there is in this disease almost a continual breathing forth, that thrusts out the recrements of the nutritious Juyce, and all the thicker parts of the Serum towards the circumference of the body.

2. The Saffron-coloured urine, and which dyes Linen with the same colour, un­doubtedly is a sign of the Jaundice: it is tinged after this manner by the yellow Bile or Choler, or by the Salt and Sulphur burnt and plentifully mixt with the Serum: for the yellow Bile is necessarily begot from the yoked heat and motion of the blood; but for this the Gall bag is designed by Nature, for the separating it from the mass of the blood, its passages being rooted in the Liver: But if such a separation be any ways hindred, that humor flowing back in the blood, and copiously heaped together, infects the skin with its yellowness, the blood, and especially the serous Latex. The Saffron-coloured urine differs from the flame-coloured, because in this only a certain portion of the more thin Bile is poured into the urine, but in that the more thick part, and much more plenty: besides, in the yellow Bile the Sulphur, with the Salt, being joyned and long circulated, is fully dissolved by it, that it becomes like paint, imparting to every subject a Saffron-coloured tincture; as when common Sulphur and Oyl of Tartar are mixed together. But what things cause a redness in urines, without the restagnation of this Bile, happen after the same manner, as in the Lye of Ashes: where the particles of the Sulphur, without any previous disposition from the saline, are forthwith put down with them in the Liquor.

3. It remains that we speak next of red Urines, which are of a divers habit, nei­ther do they always depend on the same causes, nor plainly denote the same kind of distempers; we shall briefly run through the chief differences and proper significa­tions of them. First, the liquor of the urine is either red of it self, and remains after the same manner, nor is the colour altered by the setling or sinking down of any of the parts: or secondly, the redness of the urine chiefly owes its colour to the Contents, which being setled to the bottom, the liquor grows yellow, or is less red. The distempers that these kind of urines are wont to shew, are chiefly Feavers, and a confirmed Scurvy, and Consumption. We shall consider the reasons of each.

1. When the Urine that is made red so remains, it is first either of a mean con­sistency, and somewhat clear, and then it owes its colour to the Salt and Sulphur, being burnt more than usual, and so boiled more copiously in the Serum: or second­ly, such an urine is red, and also troubled and cloudy: but this, besides the contents of Salt and Sulphur, has boiled in it some earthy particles also, which indeed being impacted in the Pores and passages of the serous Latex, do not descend: because the liquor of the urine is destitute of convenient spirits, which may segregate all hete­rogeneous things, and drive them to the bottom, as is wont to happen usually in dead drink, or Beer growing sour by reason of Thunder; where the liquor is infected with a troubled Feces, and by reason of the defect of spirits, will not grow clear; wherefore this kind of urine is a very bed sign in Feavers, because it shews such a con­fusion in the blood of adust and to be separated matter, such as the vital spirits are not able to master by taming and subjugating it.

2. Sometimes the Urine is made red, by reason of its contents; which setling in the bottom, the liquor becomes of another colour: but these contents, as before we hinted, are twofold, viz. now thin, which are the remaining matter, or adust re­crements after the burning forth of the blood; now more thick, to wit, the dege­nerate particles of the nutritious Juyce; both these being torrified, and separated from [Page 11]the burning blood, are partly thrust forth by Sweat, and partly mixed with the se­rous Latex, thicken its consistence, and heighten its colour, viz. so long as these kind of contents are included in the Pores and passages of the liquor, they are sustain­ed, the colour of the urine appears more deep, and the consistency thicker: but these being precipitated to the bottom, both the redness and thickness of the liquor are lessened. The reason of this shall be given anon, where we shall speak of the Causes of the Colours, and also of the Clearness and Cloudiness of Urines: we shall now inquire, what is the reason of the difference, that red urines are wont to be made both in Feavers, and also in the Scurvy, Consumption, and perhaps in several other distempers.

1. In Feavers, the liquor of the Urine is filled with redness, because of the more plentiful dissolution of the Salt and Sulphur, and their particles copiously boiled in the Serum; for whilst the blood and humors grow hot, from the feaverish cause, by reason of the heat being more fully inkindled, the saline and sulphureous little bodies, being burnt and torrified, are more dissolved; and being boiled in the se­rous Juyce, impart to it a deeper tincture: Even as if the Lye of Ashes be boiled over the fire, it grows more red, than if it were only made by infusion. Also in Feavers, the contents of the urine most often increase its colour, viz. by reason of the intem­perance and deflagration of the blood, both the degenerate particles of the nourish­ing Juyce, and also other matter (as it were the Ashes remaining of the burning of the blood) are burnt together, as it were into a reddish Calx; which being included in the Pores of the urine, renders its colour deep, and afterwards sinking down, makes a sediment like red Oker.

2. In a long Scurvy, the liquor of the Urine grows sometimes so highly red, that it cannot be greater in a burning Feaver: if such urine be evaporated, or exposed to distillation, it will shew great plenty of Salt, with a muddy Feces or dregs: where­fore it seems to be manifest, that this deep redness doth chiefly arise from the Salt, (as we have already hinted) by this Experiment; because in Scorbutick people the saline particles, which ought to be made volatile, and so constantly exhaled by trans­piration, become fixed, and being hindred from a flux, are heaped together more plentifully in the distempered body. The Salt remaining within, is variously coagula­ted with Sulphur and Earth, and then is continually dissolved: and from this diverse coagulation and dissolution, the to be admired Symptoms of this Disease are caused. Also from the saline little bodies plentifully dissolved with Tartarous feculencies, and diluted with the Serum, urines are filled with an high redness; to which most often happen in this inveterate disease vices of the Liver and Gall; for when these Inwards, being either obstructed or other ways depraved, cannot perform their tasks, for the separating the adust particles of the blood, they being more fully heaped up in the blood, are dissolved in the serous Juyce, and infect it yet with a more lixivial tin­cture. And if the adust particles of the Sulphur do excel the rest of the fixed and scorbutick Salt, the yellow Jaundice happens together with the Scurvy, and the urine fixes to Linen a Saffrony tincture. But if they be less than they, and that the saline particles excel, the Scorbutick distemper only is produced, in which the urine is in­tensly red, yet does not dye the Linen. I am perswaded that it is thus; because, when I have opened the dead carcasses of many dead of the Scurvy, in whom there was a red urine, I observed that the Liver or Gall was in fault: In some the Liver was wholly without blood, and dry like a Cows Udder; in others the bag of the Gall was empty, and nothing in it; in others it was beset with little stones; in others it was filled with filth, not bitter; in all these Inwards were so distempered, that the secretion of the Bile was hindred.

3. By reason of this kind of dissolution of the Salt, Urines sometimes grow red in Arthritick diseases: for besides the Gout (in which such urine is often made) I have observed in some a painful distemper, and as it were like a Feaver, caused, with a very high-coloured urine; they had wandring pains, now in this place, now in that, grie­vously tormenting, that the sick were scarce able to stand, or to stir their limbs: they were obnoxious to wakings and frequent sweats; they were also troubled much with thirst, and heat of their mouth: and they had a urine highly red, with a plenti­ful red sediment. In the mean time it did not appear, either by the Pulse, languishing of the Spirits, or Head aches, that the blood grew excessively hot, or that they had a Feaver. Wherefore I suppose that this kind of distemper doth chiefly consist in the nervous stock, and depends on the exorbitances of the saline Principle, rather than the sulphureous.

4. Also in the confirmed Phthisis or Consumption, especially if an Hectick Feaver be joyned with it, there is a red Urine; the reason of which is, if at any time an Ulcer is excited in the Lungs, the putrid filth from thence being mingled with the blood sliding by, causes in it almost a continual effervescency, whereby the sulphu­reous and saline particles being more plentifully dissolved and boiled in the Serum, affect its liquor with redness: besides, by reason of the blood being defiled after this manner, the nourishing Juyce degenerates almost wholly into putrefaction, by whose recrements the urine being filled, grows more red, and is very much stuffed with contents: The sign or note of this is, that the sick for the most part grow hot after eating, and that they are troubled with an heat through their whole body, fol­lowed with a nightly sweat; besides, their urines yield a thick and copious sediment, to wit, when the nourishing Juyce, being mixed with the blood, is not assimilated, it stirs up in it a fervour, and being degenerate into an extraneous matter, exhales partly by sweat through the Pores of the skin, and partly being transmitted to the urine, very much heightens its colour and consistency.

Thus far of a red Urine, whose several species, but now related, have more de­grees of intention and remission, accordingly as the causes, altering the colour and consistence in them, are either weaker or stronger.

4. As to what belongs to a green and black Urine, I confess I have never seen those kind of deep colours (exactly like those of Leeks and Ink) in any urine: but I imagine I may have seen the appearance of a greenish colour from a more deep yellow, and of a blackish urine from the same with a cloudy and somewhat a dark mixture, and from thence called by Authors a green and black Urine. But those urines, coloured after that manner, are esteemed either signs of the Jaundice, or of being distempered with some virulency of the blood, if they continue so con­stantly for some time: or such urines, as occasion offers, are variously changed, and are now of this or that, and presently of another colour. So I have known Hypochondriacks wont to make such urines, as it were critically for some time, and then afterwards to render them like sound men. As to the first, when the Jaundice is very great upon them, that the adust portions of Sulphur and Salt remain a long time in the mass of blood, they acquire by a long incoction a fulness of the yellow colour, at first green, and afterwards black, and impart the same to the Serum: For if the yellow Bile, being taken out of the bag of the Gall, and put into a Cucurbit, be exposed to the gentle heat of a Bath, the same in a short time will grow green, and afterwards appear like the blackest Ink: wherefore in the black Jaundice, which is only the yellow carried forth into a worse state, by its long stay or continuance, there is nothing more usual than to make black urines. Besides, these kind of urines sometimes appear in a malignant Feaver, and in the Plague, also often from drinking of poyson, and in this case it is for the most part a sign of death, because it argues the blood greatly corrupted, and the spirits profligated, and the bond of the mixture loosned, as it were the deadly or mortified distemper: even as where some part of our body, being distempered with an Ulcer, is afterward taken with a Gangrene or mortification, forthwith the flowing corrupt matter, which was at first white, waterish, or yellow, becomes black. Wherefore in the forementio­ned distempers, when the urine grows black, the Serum and the blood being wholly vitiated, the skin also is dyed outwardly with such a colour. As to what belongs to urines periodically tinctured with a greenish colour, and especially with black (which happen often to Hypochondriacks) it is most likely, that such arise from the melancholick Feculencies laid up in the Spleen, and from thence, by reason of its con­gestion, too much flowing forth sometimes, and confused with the blood: for such a matter, being often poured into the Ventricle in some men, stirs up black Vomi­tings, also in others, the same being supp'd up from the blood passing through, may impart suffusions of the same colours to the serous Juyce.

So much for the Colours of Urines, of which the more pale arise from too much Crudity, almost all the high-coloured, either from the Salt and Sulphur plentifully missolved, and sometimes from the adust recrements throughly boiled in the Serum, or from the more thick contents of the urine; whether they be the Calx and remain­ing part of the aliment, degenerated in the concoction, or the wasting or melting of the pining body, or some part of it evilly distempered: what hath been said may be better understood, if the means, whereby these kind of dissolved things or contents are able variously to change the colour of the urine, be unfolded.

The causes of the diversity of appearances of colours, and their variously chang­ing, as also of the cloudiness and clearness in Urines, (as in all other Liquors) depend only on the various incidency and emersion of the beams of light, as is hinted in another place, in the Tract of Fermentation: For if the substance of the liquor be rare and thin, with open Pores and passages, that the beams of light may easily pass through, it is shining and clear like fountain-water: but if the Pores of the liquor be filled with contents, or little bodies swimming in it, so that the luminous beams are broken in their passage, but so that at length they may shew themselves, accord­ing to those various manners of refraction and emission, there will appear a Citron, a Saffron, or red colour in a yet clear liquor. If that, in the little spaces of the Pores yet more obstructed, the light cannot pass through, there is a darkness induced: but then if the immersed beams be a little or nothing reflected, the liquor will appear of a brown or dark colour; but if they are beaten back, according to the diverse manner of reflection, a white, ashy, or some other kind of appearance, is induced. From this being supposed, according as the liquor of the urine, sometimes almost wholly deprived of Salt and Sulphur, and other things dissolved, easily admits of light, sometimes either very much stuffed, or else moderately with these kind of contents, either distorts the beams falling on them in their passage, or wholly imbibes them, or lastly beats them back; it were easie to explicate all the Phaenomena or appea­rances of colours and their consistence.

It often happens, that the colour of the same Urine is variously changed: for what is made red, being exposed to the air, becomes white, or of a dark colour, and then after a long time of a Citron colour: the reason of which is this, if I am not decei­ved, this kind of urine, when it is made, is red, because the Pores of the Liquor are very full of contents; yet so long as they are dilated with heat, they transmit the rays of light, (although variously distorted) that they may at length shew themselves or appear; but this urine is no sooner exposed to the cold, but that the Pores being straitned, the site and position of the parts is changed in the contents, and by that means the passage of the beams of light is hindred: wherefore the liquor presently becomes cloudy, and according as those beams are reflected after this or that man­ner, a white, or brown, or some other kind of colour is induced: but at length the contents falling down towards the bottom with their weight, the Pores being freed, transmit again the rays of light, and do not distort them; wherefore a clear or a Citron colour appears.

From these things which have been spoken concerning the Colours of Urines, may appear what is the cause of the various consistence of urines. For as the particles of Salt and Sulphur, of the adust matter, or nutritious Juyce, depraved in the assimila­ting, are more or less boiled in the Serum, urines also get their more thin or thick consistency. It remains next that we speak more clearly of the Contents in preter­natural Urines, whereof we have often made mention.

CHAP. V. Of the Contents in the Urines of sick People.

WE suppose the Contents in the Urines of sick people to be twofold, viz. either universal, which proceed from the mass of Blood, and of the ner­vous Liquor, and respect the habit of the whole Body; or particular, which are the layings aside or excrements of one bowel, or part ill affected, of which we shall speak anon. Those of the former kind, which come away from the whole, are either natural, viz. Filaments or small threads constituting the Hypo­stasis or settlement, as in sound Urines; or preternatural, which chiefly are parti­cles of the nutritious humour degenerate from assimilation, and constitute the more thick bodies of the sediment in Urines; and lastly to these, (if there be a feaverish intemperance) the adust matter of the blood after deflagration, and diluted in the serous Juyce, is added, and increases the bulk of the Contents.

But these Contents, both natural and preternatural, of Urines, represent them­selves after a various manner, as the blood more or less unduly grows hot, also as [Page 14]the aliments in the bowels and vessels are variously concocted, and either the super­fluities or corruptions of the Chyme, from thence made, are washed away with the Serum: for if the nourishable humour transmitted to the blood, is not all perverted, but a great portion of it, laid upon the solid parts, is changed into nourishment, some parts of this also rightly made, being mixed with the Serum, impress yet some marks of an Hypostasis in urines: Also from the adust or degenerate matter, a pre­ternatural sediment is framed, yet little and thin, neither doth it wholly blot out the appearances of this natural. Wherefore in the beginning and declination of a Feaver, sometimes also in a Consumption, or a Cachexy an Hypostasis, though not so perfect, is perceived. If that the greater portion of the same Chyme, growing hot with the blood, by reason of the immoderate heat, is perverted into an hetero­gene matter, which afterward is sent away with the Serum, as hurtful and unpro­fitable, presently an obscure and imperfect Hypostasis appears; and besides it, very many contents are seen in the urines, which heighten their colour and consistency. Such an urine, which contains an Hypostasis, though imperfect, together with other things of the same kind dissolved in it, if it be kept in a warm place, the Hypostasis will be perceived alone; but the rest of the contents, comprehended in the pores of the urine, dilated by the heat, are made wholly inconspicuous or not to be seen: yet afterwards the little spaces of the Pores being straitned by cold, the same contents are precipitated, and by that means they render the site and position changed, and the urine troubled and cloudy, and blot out the appearance of the Hypostasis. These kind of urines in the better state of Feavers, in a Catarrh, Cough, difficulty of per­spiration, fulness of humours, and in the more light Dyscrasies are wont to be made.

But if in the more grievous state of sickness the Concoction be wholly vitiated, and the whole nutritious Juyce changed into a putrefaction, these kind of contents also may be perceived in the urine without an Hypostasis, and signifies variously in diseases, after their various ways of being precipitated, and sinking down, and constituting a diverse kind of sediment; to wit, as the separation of the parts suc­ceed soon or late, or not at all; and as the matter falling down shall be little or much, or also of a white, red, or dark colour. I will briefly run through what is most no­table and worthy observation concerning this thing.

1. This kind of Urine being full of contents, is not sometimes at all precipitated, (unless the substance of the liquor be dissolved by putrefaction a long time after) but remains a long while troubled and somewhat cloudy, with little bodies swimming through the whole. The reason of this is, either because these contents are too much incocted in the Serum, so that the spirits implanted therein, cannot separate the pure from the impure, the thick from the thin; as may be perceived in brewing Beer, if that the Mault be too much boiled, the liquor shall never grow clear: or else the urine remains troubled, because it is wholly destitute of spirits, which may compel the parts of the liquor into the motion of Fermentation; as it usually comes to pass in Beer growing sour by reason of Thunder, or of immoderate heat, and being infected with a troubled Feces or Lee, will scarce ever be rightly made clear again. This kind of urine is perceived for the most part in very dangerous Feavers, and sometimes in a desperate Cachexy, and always portends evil.

2. Sometimes it happens, that the Urine is so full of contents, that it begins to be troubled whilst it is yet warm. I have often observed it, after this manner, in a slow Feaver, whose heat was gentle and more remiss, to wit, in which the particles of the nutritious crassament or substance are depraved, but being a little subdued by heat, or boiled in the Serum, they easily fall out of its pores: as when common Sulphur is boiled in Lye, if that before it be perfectly dissolved, it be taken from the fire, the liquor at first clear and red, by reason of the quick precipitation of the dissolved matter, becomes presently troubled, dark, and of a somewhat whitish colour.

3. But what most usually comes to pass, that this sort of Urine, big with con­tents, as long as it is hot, and some time after, seems clear and perspicuous when it grows cold, is wont to be troubled, and as if some Runnet were infused to be pre­cipitated according to all its parts; yet the same, if held near the fire, or in warm water for a little space, shall grow clear again. The reason of this is already fully unsolded, where we spake of the Causes of Cloudiness and of Clearness.

4. After that the Urine being exposed to the cold, is precipitated in this manner, [Page 15]it may be observed by what means its contents descend to the bottom; for some­times they settle in a short time: and if the liquor grows clear in the space of two or three hours, it is a sign that the liquor of the urine is not too thick, nor very much filled with Salt and Sulphur: wherefore in the beginning or declination of Feavers, when the heat is slack, such an urine is most often made: sometimes such a settle­ment follows not but in the space of many days; the reason of which is, because the consistence of the liquor is thicker than it should be, therefore the contents or dissolved things are not so easily let go from its embrace, that they may fall down to the bottom by their weight. These kind of urines are wont to be made in the state or height of Feavers, and most often precede an evil Crisis.

5. Of no less a diverse kind are the sediments which fall to the bottom. That I may pass over in this place the filthy matter, and blood, sand, gravel, and the like, deposited from some parts, I shall mention those which are the products of the whole body, and they for the most part are either white or brown, or red like Oker: If you strain urine, when it hath stood long, through brown paper, you may collect these contents. I have often seen a whiteness like Chalk, and sometimes red like Bole Armene, without doubt there is the same matter of all, to wit, the recrements of the deflagrated blood, and of the nutritious juyce depraved in the assimilating: which, as they are burnt by heat in our body, and diversly perverted, appear also in the urine under a various colour and form; even as Antimony mixed with Nitre, as it is more or less calcined exhibits a Calx, now red, now Saffron colour, now yellow, now brown: The like reason is (as it seems) of the sediments of urines, which are as it were the Calx of the sulphureous and earthy matter burnt forth by the fire of the Feaver in the Viscera and Vessels.

6. Besides these kinds of Contents, which happen in the Urines of sick people, I have often observed, that after the urine had stood a long while, something was affixed to the sides of the glass like sand, and indeed in divers figures; for now these little bodies like sand grow together with a sharp and unequal superficies, now with ridges like the Crystals of Nitre, and some shine and are pellucid like Ice. I have seen these kind of Crystals fixed to the Urinal, sometimes in the urines of those trou­bled with a Dysentery, also in those troubled with pertinacious wakings. Some­times in urines, when they have stood long, a certain Cream will swim on the top, as when Tartar is boiled in water: this kind of whitish crust growing together in the superficies of the urine, is commonly thought to be fat and fattish things, and taken for the melting of the solid parts: wherefore such as are wont to make such an urine, are presently pronounced to be consumptive, and in a desperate condition: But indeed that is only a saline concretion, which if put into the fire, will not melt, but grows hard into a crusty substance. Yea both this and the other concrescences of urines are as it were the Tartar brought forth in them by a certain Coagulation: But such a concretion depends altogether on the particles of the fluid or acetous Salt, combined with others of the fixed or Alcalisate Salt: For in every subject where there is a commixtion of the Salts of either kind, Crystallizations and Coagulations of a diverse manner are caused, either spontaneously by Nature, or may be procured by artificial separation: wherefore this kind of urine, on which this Cream swims, or that Crystals gather in the sides of the Vessels, indicates the blood to be departed from its sweet and Balsamick nature (such as depends on the volatile Salt) into an acid and corrosive, by reason of the flux and fixity of the saline Principle. Such an urine, if it be evaporated, leaves in the bottom of the Vessel great plenty of Salt: the distempers wherein it is usually sound (as I have often observed) are spitting of blood, Atrophy, or general wasting, and the Hypochondriack disposition.

In the Urines of sick people it is worth observation, whether they dye the Urinal or not? For sometimes in Feavers the urine is no sooner put into the Glass, but pre­sently it darkens its sides with a whitish cloud, and again at another time this does not happen: I suppose that the Glass is dyed, when the liquor of the urine is fuller of dissolved Sulphur than its pores can contain within themselves; as may be per­ceived in Lye, wherein common Sulphur or Antimony is boiled: Also every urine, if it stand in the Glass till it putrifie, will infect its sides with a crust or cloud, some­times whitish, sometimes reddish, sometimes of another colour: for the frame of the liquor being loosned by putrefaction, the particles of the Sulphur being loosned from the bond of mixture stick to the Glass: But in the urines of sick people some­times this presently follows, because the Sulphur is more copiously dissolved than can be included in its pores.

As to what respects the particular Contents of Urines, they indeed are manifold, and may come from many parts and places: yet they most often depend on diseases implanted about the Reins, Bladder, and Urinary passages: sometimes it happens by reason of an Imposthume in the Liver, Spleen, Lungs, of other Inward; or by reason of preternatural humours heaped up in those places, and flowing out with their fulness, an extraneous matter is transmitted into the mass of blood, and thence into the serous Juyce: but this happens more rarely, because an Imposthume being bro­ken within, for the most part pours out its matter into the cavities of the Viscera, from which there is no passage open into the urinary passages: besides the mass of blood flowing with impurities, does not presently endeavour to send them forth by urine, but oftner by sweat, spitting, breaking out of Wheals, Tumors, or by other ways of excretion. Wherefore it appears by common observation, that the other contents of urines (than which we have above cited) are chiefly sent from the Reins and their dependences; the chief of which are sand, stones, blood, matter, bits of flesh, skins, branny or mealy sediments, which for the most part signifie either the stony or an ulcerous distemper, or both together, planted beyond the emulgent Vessels.

It is an usual thing for some to void with their water, gravel or small sand of a red colour in great quantity; some of these are obnoxious to the stone in the Reins, and are frequently tormented with Nephritick fits: I have also known others without pain, or other grievous Symptom, for a long time to make a sandy water. All urines whatsoever, if they stand for some time in a leaded or earthy glazed vessel, affix this kind of red sand to the sides and bottom of the Pot, to wit, the volatile Salt of the urine is coagulated with the fixed Salt of the Metal: so when Sal Armoniac being mixed with the filings of Steel, Sea-Salt, or Vitriol is sublimated, the elevated flours grow notably red: wherefore it seems that these kind of little sands are begot in the Reins, for that the Salt of the urine is coagulated with the Tartarous feculen­cies laid up about the windings of the Reins, from whence the sandy matter is made, which is presently washed away by the serous Juyce passing through: Therefore the gravel that is so frequently made are no small parts or fragments of a greater stone, (as is commonly thought) but extemporary products of the blood and Serum washing the winding passages of the Reins.

By what means little stones are produced in the Bladder or Reins, is not to be fully discoursed in this place: But without doubt it is done rather by Coagulation than Exsiccation or Excalefaction, by drying or heating. I have observed some sick of the Stone in the Bladder, who after they have made water, were wont to void with great striving and pain a thick and viscous Juyce, which presently hardned into a scaly matter: the smell of this was like Lye, and of such a consistence as Lye eva­porated to a thickness, the liquor of which being made thick, presently stiffens into a saline hardness. Lesser stones sometimes pass through the urinary passages, and are carried out: the greater remain unmoved in their Cells. The places wherein they are usually begotten are the narrow winding bosoms of the Reins, from thence the smaller slide into the Bladder, and if not excerned, they grow into great stones. I once saw many great stones shut up as it were in a Chest about the sides of the Bladder between its Membranes; these without doubt being sent from the Reins while smal­ler, remained in the passages of the Ureters, creeping between the Coats of the Bladder, and there by degrees did increase in bulk. A Matron so distempered long before her death, cast out of the urinary passage a Membrane thick and broad, full of sandy matter, which (as appeared after her body was opened) was part of the interior Tunick of the Bladder worn and broken by the stones there included.

It is ordinary for Nephritick people, or such as are troubled with the Stone, fre­quently to void blood or matter with their Urine: for from a greater stone, and endued with sharpness, the flesh of the Reins is easily worn, and the mouths of the Vessels opened, whereby blood flowing out tinges the urine; and when a solution of unity is caused in this manner in the Reins, an Ulcer most commonly follows, whereby matter and filthy stuff are poured out with the serous water, and constitute a plentiful and stinking sediment in the urine: then the sore being more inlarged by the Ulcer, more large profusions of blood often follow, and the flesh it self of the Reins being worn away, and by degrees eaten off, is voided with the urine. I visited once an ancient Woman, who daily voided with her urine, for many months, pure blood in great quantity; besides, as often as she made water, she used to void in great [Page 17]quantity pieces of flesh, great gobbets, as it were the little Tubes of the Vessels eaten away, that it was suspected one of her Kidneys was all thus cut away from her body: yet afterwards by a vulnerary Decoction acidulated with Spirit of Vitriol, that bloody water was staid, and this Woman lives still well and in health. I knew another Ma­tron, who used for a long time in making water to void at first blood with a purulent matter, and Membranes: then the bloody water ceasing, for many years she made a waterish urine with a copious sediment, and white like snot, sinking down to the bottom of the Urinal. Afterwards when she began to want that sediment, a feave­rish intemperance followed with pains wandring here and there, with a languishing of strength, and other dangerous Symptoms: and when this sick Woman was brought into danger of her life, a Tumor arising in her left side about her Reins, and ripening into a Boil or Sore, by reason of the large flowing out of the matter, freed her: but yet an hollow and sinuous Ulcer pouring out a thin matter, remained in that place during her life: and being sometimes healed up, would presently break out again. Scarce two years after this Noble Lady having endured the suppression of her urine for fourteen days, became apoplectick and dyed. Her body being opened, her left Kidney was quite gone, in the place of it a membranous substance growing to the Loyns, infolding the extremities of the Vessels and Ureter, was grown up: some prints or marks of the Ureter remained, but without any opening into the hol­lowness of the passage: yea a certain ichor or serosity dropping out from the little mouths of the emulgent Artery, was carried outwardly into that sinuous Ulcer. The other Kidney was very full of sandy matter and small stones; besides, near the top of the Ureter a stone about the bigness of ones thumb was fixed, whose extremity was so fitted and firmly impacted to the passage or cavity of the Ureter, that it shut it up just like a Tap, and quite hindered the passage of the serous Juyce. The purulent matter comes into the urine, not only from the Reins, but sometimes out of the Bladder and urinary passage distempered with an Ulcer; and sometimes also a cor­rupt seed, or white flux, or menstruous blood are poured into urines from the Vessels and genital parts, and produce in them preternatural settlements.

4. In the Urines of sick people are often seen abundance of white Contents com­posed of most small bodies; which, when they are setled, fill up above half the li­quor, and make it white and duskish, the rest remaining limpid, and thin in the upper region of the Urinal: this kind of sediment is called Mealy, because it is like water imbued with meal. Concerning this it is doubtful, whether it proceeds from the whole mass of blood, or only from the urinary Viscera. It appears by observation, that the same sort of urine is always made in the stone of the Bladder, also sometimes by reason of the Kidney being oppressed with some great stone. I ne­ver saw such a settlement in urines without a Nephritick distemper; wherefore I have thought it almost indubitable to be always a sign of the Stone: And it seems that it should wholly depend on the juyce or humour heaped up about the bulk or substance of the stone: For where the stone is fixed in the Kidney or Bladder, the nutritious humour is there perverted from assimilation, and degenerates into a more thick mucor, which uses to be copiously heaped up; like Ichor, which by reason of a Pea put into an Issue, runs out plentifully. But this mucor or filth being washed with Serum, makes that white sediment.

CHAP. VI. Of Judgments to be given concerning the Urines of sick People.

SO much for the Anatomy of Urines, wherein are unfolded their Elements and constitutive Principles, together with their chief Accidents, viz. Colour, Consistence, and Contents, both what ought naturally to be in them per essen­tiam or essentially, and also what are wont to happen to them preternaturally, by rea­son of the body being ill affected. It will be easie for any one to accommodate this Hypothesis to practice, and to give Judgment on Urines beholding them in the Uri­nal; for from what hath been said it appears of what parts the Diseases are made known by the inspection of the Urines, and what the Urine signifies in each of them. [Page 18]Concerning this subject there hath been enough said by Authors; I shall therefore only touch upon it briefly, and lightly pass it over.

Although the matter of Urine, viz. the Serum of the blood washes the whole re­gion of the Body, and is circulated with the blood through all the several parts, yet it doth not lay open the condition and diseases of them all, but only of those to which it owes either the natural perfection and genesis of it self, or from which it receives every alteration: wherefore in some respect it shews the action and disposition of the Viscera serving to Concoction, and besides denotes the temper and motion of the blood and humours in the Vessels: but that any one should pretend to know from the Urinal, and to divine a pain in the Head, an Imposthume in the Throat, or any other Disease of any part, from whence nothing is communicated to the Serum, he shews rather his ignorance than the knowledge of any Disease.

Urines brought from sick persons sometimes are wholly like those of sound peo­ples, and then they give no light to the disease or distempered part; but it may be lawful, having inspected them, to say something negatively, viz. that the Patient is free from a Feaver, that as to the Ventricle and Concoction of the food, they are indifferently well: wherefore unless he be inclining to a Consumption, or is sick of an Imposthume, or some other disease of the unity being broken; whatsoever it be, the distemper seems not very dangerous or hard to be cured.

But in the mean time I would not have him declare any thing rashly, nor proceed farther than he can with safety return: for I have often observed in some most grie­vous distempers, viz. in a malignant Feaver, when with loss of strength, a weak and unequal Pulse, eruption of Spots, and other dangerous Symptoms, the Patients have been desperately sick, that the urines as to the colour, consistence, and Hy­postasis, have been laudable, as in sound persons, so that in such a case the Phy­sician by only viewing the Urine, as to his Prognostication had grievously erred: wherefore there is scarce credit to be given to the single testimony of the Urine, unless there be other signs agreeable; but that it is a lyar in the Plague and malignant Fea­vers, and deceives: the reason is, that in those diseases the blood is leisurely, and as it were silently corrupted, sometimes without any great fervour: and so, although its liquor be infected by Coagulation, or by mortification or deadness; yet because it doth not burn out much at the same time, so as to make an heap of adust matter, as of Ashes, the Serum is little or nothing altered from its usual disposition or tenour: Besides, sometimes when in such a sickness the blood grows very hot, whatever of ex­crementitious is heaped up in its mass, is presently transferred to the Brain and ner­vous stock: wherefore the serous water being free from preternatural contents, re­mains after its usual manner; besides this case, when the Urines appear of a deep colour, troubled, and without any sediment, there is no reason why the Piss-prophet should make a Prognostication.

As often as the Urines of sick people are unlike those of sound, either something natural is wanting, or what is preternatural is added, or it happens both together.

1. There may be wanting Colour, Consistence, Contents, and Quantity. If the Colour be more remiss than it should, and the Liquor paler, it indicates Crudity, and a defect of making Spirits, to wit, that the nourishing Juyce is not rightly con­cocted or exalted either in the Viscera or in the Vessels; so that the saline and sul­phureous Particles being carried out together, following the distribution as it were the distillation of the Serum, might throughly stick to the same, and impart also to it the tincture: wherefore such Urine being viewed from these kind of Symptoms, you may unfitly divine, that there is a weight in the Ventricle, want of Appetite, evil Digestion, a tension in the Hypochondria, an unfitness for motion, sleepiness, difficult breathing, and a frequent palpitation of the Heart upon exercise, a pale colour, a swelling of the Feet and Belly, you may say they are in danger of falling (if not already fallen) into a Cachexy or Dropsie, and if it be a Maid, that she is troubled with Longings and the Green-sickness.

If the Colour of Urines be remitted in a Feaver without a Crisis, it is a sign that the fermentative matter or adust recrements of the blood are separated from the bosom of the blood, and fixed somewhere, which for the most part happens in the Brain; and for that cause such Urines use to foretel a Delirium or Phrensie; in those troubled with the Stone, a sudden alteration of the urine into a pale and watry co­lour, denotes the approach of a Fit.

A copious and pale Urine often shews the too great resolution or melting of the [Page 19]Salts, by reason whereof the serosities are sent away as it were in a flood from the whole body, and chiefly from the nervous parts: such an Excretion sometimes is healthful, and as it were critical, when the superfluities happen only to be carried away: sometimes it is symptomatick, and causes a great debility, to wit, because the nutritious Juyce and the good humours are purged out.

If the Consistence be thin, and the Liquor pale, it argues Crudity, want of Spirits, or too much Drinking, or the Nephritick distemper: if it be of a flame-colour, it is a sign of an intermitting Tertian Feaver.

If the Contents be wanting, and it be pale, want of Concoction is signified, and a Cachectick distemper of the body. But if it be of a Citron colour, and the consi­stency mean, without Hypostasis, you may suppose the Patient to have used too much labour or exercise; or to be frequently distempered with Sweats in the night, or perhaps to have an Atrophy, or general wasting, or to be inclining to a Con­sumption.

If the Urine be continually made in a lesser quantity than it should, unless there be a larger transpiration, it is a sign that the blood is not sufficiently purged from the serous Juyce: wherefore there is a necessity that it become more watry, and that at length a Cachectical disposition of the body, or a Dropsie be brought in. But if it be suddenly suppressed, or made with pain and difficulty, it is a sign of the Stone or Gravel.

2. Something is added to the Urine, to wit, when the colour is heightned, and in the mean time the consistency and contents shew themselves in due measure, there may then be a suspicion of a Feaverish or Hectical distemper: perhaps some evi­dent cause may precede, as the use of Baths, Heat, Surfeit, or immoderate Exercise, which might have heated the blood; or Cold may have heedlesly been taken, whence may arise a shutting up of the Pores, and difficulty of Perspiration. If the urine be of a Saffron-colour, and tinges the Linen with yellowness, you may say it is the Jaundice: but if it be of a Saffron-colour or red without a Feaver, and doth not dye Linen, it shews for the most part the Scurvy or Hypochondriack disposition.

Though the Colour and Hypostasis may be in good order, preternatural Contents are often in the Urine; therefore when it grows cold it is troubled, and makes a sediment sometimes white, and then there is a suspicion of the blood's overflowing with filth, also of an impure Ventricle stuffed with excrementitious matter, or with Worms; sometimes red, which often happens by reason of Transpiration being hindred, a Consumption, and sometimes by reason of a Surfeit, or the beginning of a Feaver.

Preternatural and thicker Contents are sometimes in Urines, shewing themselves naturally, which denotes a distemper of some part about the urinary passages; whence Matter, Filth, Blood, the Whites, corrupt Seed, or the like, are mixed with the Urine: and you may easily know by asking how, and in what place the Patient is ill, what part is distempered; and the straining the sediments of those urines will shew what the disease is, and you may be more sure of the nature of the di­stemper.

When Urines have stood some time, copious white sediments are thence made; it is not easie at first sight to know from whence they come, viz. whether from the whole mass of blood, or only from a particular bowel imployed for the preparations of the Serum or the Seed. For the impurities of the blood and nervous juyce being deposited under a mealy species in the bottom of the Urinal, are wont to cause a suspicion in the Physician of the Whites in Women, and of the Running of the Reins in Men: such like contents are also seen in Urines, which proceed from the urinary and spermatick parts. Amidst these ambiguities, left you should guess rashly and confidently by the urine, and assert uncertain for certain things, and falshood for truth, the difference of these kind of urines ought to be indicated after this manner. If the contents be universal, and their signs be to be applied to the mass of blood; for the most part these presently after the making (unless sometimes by chance in a Critical separation) are wholly inconspicuous (as in a thinner substance,) then the urine being troubled by cold, they descend slowly to the bottom; and being setled, and the Urinal heated, they disappear again. But if these white settlements are sent from a particular nest, they presently disturb and thicken the urine newly made, are soon precipitated, and vanish not by heat. But that it may appear to what bowel these kind of particular contents should be ascribed, 'tis easily made known to Lear­ned men by other circumstances.

3. The Urine is sometimes wholly altered from the natural state; the colour and contents which should be therein are wanting, and strange things are in their place; then indeed is indicated that there is an intemperance in the whole body, and that the Concoction in the Bowels and Vessels is depraved; you may say the Patient is sick of a Feaver; and thence by asking, you may learn and presently pronounce that he is distempered with the Head-ach, Thirst, Heat, queasiness of Stomach, want of sleep, and by consequence with other Symptoms.

It happens sometimes, that the Urine declines from its natural state, yet not to shew the distemper the Patient complains of, but either the cause of the disease, or the consent of some other part with the distempered; as if any one should complain of a cruel Head ach, or trembling of the Heart, and make a watry Urine, that doth not denote those distempers, but only a crudity in the Ventricle, and some obstructions about the Spleen and Viscera, which may be the cause of those distempers: I say in this case, the urine being inspected, the chief indications are taken about the Method of Curing, and we must not use Cephalick or Cardiack Remedies, but either Ca­tharticks, which cause Vomit or Purging, or Openers, and especially Chalybeats: But the urine is sometimes vitiated, and yet its signification is wholly a stranger to the distemper the Patient complains of, as if any one were subject to the sleepy dis­ease, or a Lethargy, and makes it red and full of preternatural contents, its inspe­ction suggests chiefly coindications, viz. that we insist not on too hot, but tempe­rate Remedies.

The chief use of Inspection of Urines will be for the observing the state and pro­gress of every disease, as also the alterations towards health or death. For in Chro­nical diseases, by daily inspecting the urine, is made known to the Physician, by what degrees the sickness may increase day by day; at what time purging or altering Re­medies will be most fit, and what Medicines will be most profitable: hence is to be observed, whether Nature prevails on the disease or not; and a most certain Prognostication may be drawn from hence, either of the hope or danger of health; to wit, according as the signs of Concoction or Crudity appear in the Urines. In acute diseases, hence the state and height of the Feaver may be best known, at what time the Crises may be expected, and with what success; when it is best to insist upon Evacuations, and when on Cordials. The Compass is not beheld with more cer­tainty and diligence by the Mariner or Steers-man, than the appearances of Urines ought to be observed by the Physician for fit times and ways of Curing.

These were what I had to had to say concerning the Judgments of Urine, not col­lected from the vain Traditions of Quacks, but what are consonant to reason and truth. Besides I know there are ordinarily delivered by Medicasters and Old women almost an innumerable company of Rules and Directions of Urine-divination, that the Urinal is no sooner inspected, but they will undertake to divine, whether it be a man or a woman that is sick, how long they have been sick, what their disease is, and whether the distemper shall end in health or death; whether the Patient be sub­ject to the passions of Love or Sadness, whether a Woman hath conceived with Child or not, or whether it shall be a Boy or a Girl, and an hundred other the like; in which using a vain conjecture, they either impose by their confidence on the minds of the credulous, or (which is more frequently their custom) by a cunning craftiness they other ways sift out the matter by inquiring, and falsly ascribe it to their know­ledge in the inspection of Urine.

CHAP. VII. Of the Examination and various ways of proving of Urines.

ALthough the business of the Examination and Inspection of Urines seems com­monly only a simple thing (viz. the Medicasters and Quacks for the most part behold the Urine sent in a Glass, shake it a little, and presently give Judgment) yet to those who honestly endeavour the recovery of the sick, the matter seems a little more intricate, and they use to observe several circumstances concerning Judgment by Urine; which being omitted, nothing indeed can be certainly or di­rectly [Page 21]learnt in the Medicinal Practice from the Urinal. Moreover, in some disea­ses, besides the mere inspection of the Glass, there are other ways of tryal to be had, by which, what lies hid in the Urines, and out of sight, may be made clear: from whence some not unprofitably taking care of the separation of Urine more accurate­ly, have used to evaporate, distil, putrifie, and precipitate them. Wherefore we shall speak briefly of the right manner of inspecting Urine, and in some cases of the Analysis or separation variously to be instituted.

When the Urine of the Patient is offered to the Physician, if it hath first stood for some time in the Glass, and if the liquor be clear, the Hypostasis as it were gathered into a little cloud, and if the rest of the contents sink down to the bottom, there is nothing more wanting, but that forthwith a prognostick sentence may be given. But if the Urine be newly poured into the Urinal, or be troubled by a former sha­king, you must stay till the confused parts be separated, and the settlement have acquired its due place. If the Liquor be full of contents, and the Pores straitned, it becomes troubled and dark, and the Glass must be put in a warm place, till the urine grow clear again, and then let it be placed for some time near the fire, that whilst the preternatural or more thin contents are absorpt by the Pores dilated by the heat, the more thick may fall down to the bottom, and the filaments or little rags making the Hypostasis, (if there be any) may be gathered together below, or in the middle region; for so will appear what is the power of Nature, and what of the Dis­ease: Also in Feavers, the degree of heat and effervescency, the concoction or depra­vation of the nutritious Juyce, also the congestion or heaping together of the adust matter in the blood, and its separation begun, or wholly frustrated, may somewhat appear by the signification taken from Urines; wherefore you ought to proceed after this manner, when the urine is brought from far, to wit, whose Particles are di­sturbed by much shaking, unless it be kept for some time in a warm place, they will not easily get again their due place of position. But if you often visit any Patient that keeps his bed, it will be convenient, that the urine newly made, and put into an Urinal, be placed near a Stove, where, whilst it grows moderately hot, the several parts may, after the best manner, be disposed to a settlement without any trouble or disturbance.

Afterwards the Urine thus naked, and as it were disrobed from any covering, is offered to the sight, the next caution will be, lest any of its Phaenomena or appea­rances being accidentally contracted, and not properly belonging to it, may impose upon the Physician: which indeed sometimes happens, by reason of alterations cau­sed in them by food taken, and which chiefly consist in the colour and smell of urines, being variously changed besides Nature, and the expectation of the Physician.

For it is an errour commonly committed, when the Urine being yellow, and tinging the linen by the taking of Rhubarb, Saffron, Sanders, and the like, undoubtedly to be­lieve it a sign of the Jaundice; also the urine being imbued with blackness by the ta­king of Cassia, to attribute it to the melancholick Tumor or black Bile; also when the urine is deep colour'd by taking of Pulse-broth, or a Decoction of Madder, or other drinks, we falsly suppose it to indicate a feaverish intemperance. It often happens from the drinking plentfully thin liquor, the urine is lessened of its high colour beyond expectation, and heightned by the drinking of strong drink or hotter things: unless the Physician take notice of these kinds of mutations, he will give but a false Judgment concerning Urines by looking on them. When therefore the colour is changed in the urines without any manifest cause, the manner of living must be inquired into, if that the alteration proceeds from what is eaten or drunk, that it may not be wrongfully ascribed to the disease. A question will here arise, why forasmuch as most things taken in at the mouth, before they go into urine, wholly lose all their colour; yet some others, which being eaten, so pertinaciously impress a tincture to the Serum, that they pass untouched through all the strait turnings and windings of the passages? The reason or cause of which consists chiefly in this, that some mixtures have the constitutive parts of their colour or dye very subtil, and those highly volatile; where­fore these being taken only in a small quantity, dye the whole mass of the Chyle with their colour; and from thence the nutritious Juyce conveyed to the blood, ascends co­loured, and its vehicle, viz. the serous Latex, is sent away still dyed or tinctured.

What the odour of Urines of sound people may be, is obvious to every one that can smell, viz. whilst it is fresh made, it is not very ungrateful, by reason of the sulphureous and saline Particles bound up in the substance of the liquor; when it hath [Page 22]stood so long, that the Sulphur begins to exhale, sharpned with the Salt, the mix­ture being loosned, it putrifies and stinks grievously. Besides we may observe, that sometimes there arises from urines fresh made, a sweet odour like Violets, and some­times they offend the nose with a very ungrateful stink. The former doth not depend either on an healthful or unhealthful condition of the body, but is produced only from things taken: Turpentine, Nutmeg, and other Gumms and Spices taken in at the mouth, though of a diverse nature and operation, impart a like suavity or sweetness to the urine. The reason of this seems to be, because in these kind of mixtures very many particles of the purer Sulphur (that is imbued with Spirits) are eminent; which, for that they are volatile, being confused with the Serum, are not contained in the bond of the mixture: wherefore the urine being made, these alone leap out, and not accompanied with others of the stinking urine, and so diffuse a grateful odour; which, although it proceeds from divers kind of things eaten, yet remains still after the same manner like Violets, for that in all, those sulphureous Particles are set free by digestion from the others joyned with them in the same concrete, nor are infected by different ones from the urine. But as to what respects the stinking urine, that sometimes proceeds from an Ulcer about the Reins, Bladder, or urinary passages; sometimes also it is raised from a too hot intemperance of the Reins, or of the whole Body: for when the Sulphur is deeply boiled in the Serum, its particles being sharp­ned by the Salines, (for that they are less closely shut up) do presently evaporate, and grievously affect the sense of smelling; but besides, sometimes urines contract a stink from things eaten. For the Balsam of Sulphur, Garlick, Asparagus, Cider, Rhenish Wine, and many other things taken at the mouth, do cause a strong smell in the urine. If the reason of this be demanded, we say that such things which impart a stink to the urine, also provoke it in a more plentiful quantity: wherefore it seems that these sort of things being taken, fuse the blood, and greatly hasten the precipitation of the Serum: and when by this means the serous Juyce is pulled away as it were abruptly from the blood, the frame of the liquor is made lax, nor are its parts exactly mixed, nor contained in an equal bond of disposition: wherefore when this urine is made from the body, its frame or substance being before loosned, the particles of the more gross Sulphur (that is combined with Salt) presently breathe out, and so diffuse a stinking smell. For urine thus altered by things taken, seems very like to Lye, wherein Antimony or common Sulphur is boiled, and is aster­wards instilled into some acid thing, because in this Decoction, as also in such urine, the frame of the liquor being unlocked, the little sulphureous bodies leap out, and affect the sensory with a stinking smell.

If that any one more curious in the search of Urines, shall seek further than the examination of the sight and smell, he may easily, by a divers manual operation, re­solve them into parts, and as it were dissect them to the life, and thence draw Medi­cinal directions of no small moment; for that in many Chronical diseases where the Dyscrasies of the blood are more exactly to be sought into, that the proportion and temperature of Salt and Sulphur may be truly found in it, it is sometimes convenient to evaporate urines, or to distil them; something also is to be learned from them, being precipitated, or loosned by putrefaction. I knew an honest Woman greatly afflicted with a scaly filthiness of the skin, which she was daily wont to scratch off in great plenty, as it were a branny matter. Her urine being evaporated in a little Skillet, left sticking to the sides of the Vessel, a crusty and salt sediment, like the excrement of her skin. Not long since I evaporated the urine of a Gentleman, grie­vously subject to convulsive motions and painful stretchings out of the Muscles, in the bottom of which there remained a quantity of salt and tartarous matter, ex­ceeding the weight of half the liquor. By this means it will be an easie thing to find the proportion of the saline Principle in the blood and humours: but whether this Salt be volatile, or becomes fixed beyond measure, the distillation of the urine will presently shew: For if the Spirit (so called) be copiously drawn out of the urine, and that besides the Salt ascends into the Alembeck, it is a sign of volatilization: but the contrary to this argues the fixity of the Salt.

As the evaporation and distillation of the Urine shew the power of the saline Prin­ciple, so the precipitation, putrefaction, and Sulphur lay open the thicker contents of the Urine, as it were in weight and measure. As to the former, although the liquor of the urine be salt, and often big with contents, yet for as much as its saline Particles are not (as it is wont to be in most Menstruums) either wholly in a state of [Page 23]fixity, or of flux, but for the most part volatile, therefore it is not easily nor pre­sently by any salt infusion subject to putrefaction; the Spirit of Vitriol and other acetous things effect nothing: the Salt of Tartar stirs up a little perturbation. But the solution of Alum, for that it greatly constrains into a little space, presently di­sturbs the whole liquor extremely, and delivers all the contents of the urines, as they were thrust out of their dens, to be seen openly by the eyes. Wherefore by this means, without any long stay for settlement, you may presently know how much of sulphureous and earthy matter is deposed from the mass of blood for recrements in the bottom.

The putrefaction of Urines is wont to exhibit the several particles of every kind, yet more distinct, and disposed as it were by themselves; for if the urine be left to stand unmoved for many days in the Glass, the colour, odour, and consistency will be very much altered, for the colour will be deeper, the smell ungrateful, and highly stinking, the consistency thicker, and will have on the superficies a downiness or hoariness, sometimes whitish, sometimes bluish; there will be also fixed in the bot­tom of the Vessel a thick and copious sediment, and often on the sides a sandy or tartareous crust, of a whitish or Ash-colour. From these kind of appearances, and as the urines sooner or later putrifie, and so are more or less altered from their former state, it may be conjectured what the proportion of Salt or Sulphur may be, whether of them exceeds the other: also no unfaithful Judgment of the quality and plenty of the earthy matter or the contents may be taken from hence.

And thus, Sir, at length you have the Doctrine or Method of Separation of Urine, such as our unskilfulness hath rendred it: I desire you would be pleased not only to pardon the errours and barrenness of this Discourse, but also to excuse it in other things, because at first writ by your perswasion, and then by your command and request made publick. Wherefore pray take care of this child hardly brought forth and almost an abortive, and as it were exposed and deservedly laid at your door, without portion. Farewel.

CHAP. I.

AMong the various parts of an animated Body, which are subject to Anato­mical disquisition, none is presumed to be easier or better known than the Brain; yet in the mean time, there is none less or more imperfectly un­derstood. All of it that appears, and is commonly described in the fore­part or forehead, is beheld almost at a sight or two after some rude cutting up; but if you seek what lyes hid in the recesses for that end, new bosoms and productions of Bodies, before hid, are every where laid open: yea the parts of the Brain it self are so complicated and involved, and their respects and habitudes to one another so hard to be extricated, that it may seem a more hard task to institute its perfect Anatomy, than to delineate on a plain, the flexions and Meanders of some Labyrinth: Because, as we are not able to estimate the measure or to paint forth the pattern or draught of the frame of this, so neither of that, unless the bulk or substance of the subject be first searched to the bottom, and its frame broken into pieces. Hence it came to pass, that the old Anatomists in dissecting the Brain, not sufficiently attending what was placed first, what second, and what after that in the order of Nature, cut its Globe as it were into slices or parts, and the Phaenomena arising by chance from such a dissection, they easily esteemed for true parts of the Brain; when yet in the mean time, by others from a dissection otherwise made, the parts and processes of it ap­pear far different from the former. The reason of which is, because the substance or frame of the Brain and its Appendix lyes so within the Skull, that there are many swellings or tuberous risings, with several tails or little feet compacted together: all which, although distinct one from another, and are endued with figures diversly ex­panded; yet they, that they may be contained in a lesser room, are thrust as it were into the same Globe, and so complicated among themselves, that it is a hard thing to find out where the beginning and end of the Brain, as also where the limits and partitions of the near adjoyning parts do remain; further, that the several parts of the Encephalon so complicated, may retain their site, nor presently being loosned one from another, may spring forth, they are knit together into due foldings, with Fibres and Membranes stretched out from part to part. And as often as the substance or bulk of the Brain so conglobated or rolled together is cut, there is as often a necessi­ty that the slips being cut, the portions of divers parts cleaving together, are carried away with them. Wherefore that a true and genuine description of the Brain might be shewed before its substance and continuity is dissolved, before all things its whole frame or substance ought to be explicated, and the knitting of the Membranes being wholly loosned, the several parts ought to be turned over and stretched forth into their proper dimensions. By what means these things may be done, and by what [Page 56]Method the dissection or Anatomical administration of the Brain may be best per­formed, ought here in the first place to be shewn; then these things being first done, we will more largely deliver the Description of the Brain, together with the use and action of its several parts.

That the perfect knowledge of the Brain and its parts may be gained, it is necessary not only to dissect and look into mens Heads, but all other kind of living Creatures heads: for besides, that the humane Heads or Bodies are not so readily to be had, that one may from day to day behold the Brain and its frame, and carefully consider the situation of the parts, and search one after another their respects, habitudes, and dependencies; besides also, the immense bulk of an humane Head is in it self an hindrance, whereby its most intricate frame and various recesses and Appendices are the less accurately discerned and investigated: all which being reduced into an Epi­tomy, are plainly represented more commodiously in the dissection of Beasts. Where­fore when the form and composition of the Brain in a Dog, Calf, Sheep, Hog, and many other four-footed beasts, were little different (the magnitude only excepted) from the figure of the same, and the disposition of the parts, in a man, I was the more satisfied to compose a certain Anatomy of the Brain by the frequent dissection of all sorts of living Creatures. And in this imployment, for that I shall shew the com­munities and differences which the subjected parts obtain in various Animals, com­pared among themselves, and with Man; certainly from such a compared Anatomy, not only the faculties and uses of every Organ, but the impressions, influences, and secret ways of working of the sensitive Soul it self will be discovered. Concerning the Heads of living Creatures, in the dissection of which it happened for us chiefly to be exercised, it was observed, as to the chief parts of the Head, that there was a notable Analogy between Man and four-footed Beasts, also between Birds and Fishes: For when the first Inhabitants of the new-made World were produced, as one day brought forth Fowl and Fishes at once, another in like manner Man and four-footed Beasts; so there is in either twin species a like form of the Brain; but between that Child of the former, and this of the following day, there is found a great difference as to those parts. For as much therefore as Men and four-footed Beasts have got more perfect Brains, and more alike among themselves, we have ordered our Observations from their Inspection: Then afterwards we shall deliver the Anatomy of the Brain in Fowl and Fishes. And here first concerning the Heads of Men and four-footed Beasts, (as we hinted but now) we will propose a Method of Dissection it self, or of Anatomical Administration, and will at once recite all the parts one after another, and as it were in a compendious Catalogue; then we will by and by more largely draw out the Particles of the Brain and of its Appendix, so sha­dowed, in a short Table, and will design their uses and actions for the exercise of every faculty.

When therefore we had in our hands the Head of a Man, or Dog, Calf, or Sheep, its more outward coverings were taken off; concerning which, as they are well enough known, we are not at all solicitous: then the covering of the Skull being divided by a Saw or Instrument, and taken away, on every side the bones are broken off with a pair of Scissers or a Penknise to the Basis of the Skull, that so the Contents might, as much as may be, be all made plain or open to the Spectators. What therefore comes first in view is the hard Meninx including all the rest with a common covering. This Membrane outwardly and above is knit to the Skull in divers places, especially about the Sutures; but indeed about the foot or Basis it most strictly cleaves to the bones, so that it cannot easily be pulled away. Inwardly (or in its hollow superficies) it is lax and loose enough, unless that nigh all its bosoms by the insertions of the Veins, and in the Basis of the Skull by the Arteries and the Nerves it is tyed to the Pia Mater.

This same Membrane between the Interstitia or division of the Brain, and besides of the Cerebel it self insinuating it self deeply on one side, and rising up again on the other, leaves some duplicatures or infoldings, in which, being shut up above by the increase of the same Membrane, Cavities, which they commonly call Bosoms, are formed: to wit, by this means, almost the three first bosoms are constituted; but the fourth is a smooth and longish, and also hollow process of the same Mem­brane, which is sent through the Interstitia of the Brain, nigh the end of the callous body, even to the pineal Glandula. The Cavities of the greater Bosoms are severed in many places, as it were into little Cells; as it seems for that end, that the blood [Page 57]passing so through the various turnings in those ends, may be hindred from a more rapid motion.

Besides, this Meninx or Film of the Brain admits two Arteries from either side, one conjugation of which arises not far from the Carotick Arteries through the holes of the Cuniform bone, but the other from the bone of the Forehead: all which in­deed being diffused through the exteriour superficies of the Membrane, water it; but are terminated, partly in the Skull, especially nigh the Sutures, whither they convey the blood, and partly in the bosoms, where, what is superfluous is laid up. More­over, these Arteries perforate the hard Meninge in several places on the top of the Brain (as Webser observes) and impart some shoots to the Pia Mater. Lastly, the exteriour superficies of this Meninge is no where planted with so many shoots of Veins as Arteries; but from its four Bosoms (which are the veinous Receptacles of the blood) many Veins go out through the interiour superficies of this Membrane, which being inserted in the Pia Mater, are presently dispersed through its whole com­pass, and the same sliding down on every side from the bosoms, meet every where the Arteries ascending from the Basis of the Head, and being intermingled with them, constitute the manifold infoldings of the Vessels.

That these may be the better beheld, after the Arteries are sufficiently noted, let the hard Meninx be cut round near the border of the broken Skull; then let what­ever of it serves for a covering and partition to the Brain and Cerebel, be lifted up, that the goings out of the Vessels, viz. the Veins and their distributions into the Pia Mater may be considered; which being afterwards broken asunder, let the Mem­brane with its bosoms be wholly taken away; but the reliques of this Membrane, which stick to the bones at the bottom of the Skull, should be separated; so that the whole frame or substance of the Brain and its Appendix may be somewhat clevated, and moved here and there, be every where conspicuous, and at length taken from the Skull. But that these things may be performed, you must begin from the an­terior or fore part, where the bone of the Forehead separates it.

Therefore if the prow of the Brain, hid under this bone, be a little lifted up, the mammillary processes come presently in sight, together with the smelling Nerves hang­ing to them; which being dissected near the insertion, there will appear an hollow­ness in either process. These are large and round, also full of clear water in Calves: but in either smelling Nerve a manifest Cavity is found continued on either side to the anterior Ventricles of the Brain, to which if a Pipe be put and blown into, pre­sently the whole substance of the Brain will swell.

Next the smelling Nerves about the Cocks-comb two small Arteries are seen to arise from the Skull, and to be carried towards the Interstitium of the Brain, which in truth are branches of the Carotides, which are knit to the dilated Comb before, and from thence are seen to be reflected to the anterior Brain.

These Vessels being there dissected, the coming together and going out of the Optick Nerves follow, the trunk of which being cut off a little lower, the Tunnel, and out of both its sides the Arteries called Carotides, arising out of the Cuniform­bone, do appear; which are more clearly beheld, if the Brain be lifted up. These also being cut off, and the brain farther bent back, the moving Nerves of the Eyes pre­sently shew themselves; and so from thence the other pairs of Nerves follow in order, that one pair of them being cut off, and the brain with its Appendix more lifted up, the next is still obvious to those beholding it, till all the Nerves arising within the Skull, and also the Arteries, both the Carotides, and the Vertebral being at length cut off, the whole frame of the Head may be taken out of the Skull.

But (that these Vessels may be described in the same order as they are met with in the cutting them up) two small Nerves follow after those moving Nerves of the Eyes, which, for a reason hereafter rendred, we call Pathetick. These Nerves higher than the rest, arising behind two round Prominences called Nates and Testes, (the Buttocks and Stones of the Brain) and bending down forward, and entring for a little space under the dura Mater, then coming out through the same hole, together with the former, from the Skull, are propagated into the sight of the Eye. This pair is called by Fallopius the eighth, by us the fourth.

Beneath these little Nerves, from both sides of the annulary protuberance, (which being sent from the Cerebel compasses the oblong Marrow) two Nerves of noted magnitude arise, which, after they have passed through the dura Mater, send forth another notable branch on either side straight down without the Skull, the other [Page 56] [...] [Page 57] [...] [Page 58]branch, by a longer tract, passing through both sides the Skull near the Turky Chair. These Nerves (as is shewn afterwards) having gotten a larger Province, are inlarged in the Palate, the parts of the Mouth and Face, and also their branches in the Nose and Eyes, yea they impart roots to the intercostal Nerve. We call this pair the fifth, commonly esteemed the third.

Nigh to the beginning of these, out of the lowest foot of the oblong Marrow or Pith, two lesser Nerves, endued with a single trunk, arise, which being dilated for­ward, and presently entring under the dura Mater, come out of the same hole with the moving Nerves of the Eyes, and are all carried into the balls of the Eyes. This pair is called by us the sixth.

Next to these Nerves follow the auditory or hearing pair, which indeed arises higher from the sides of the oblong Marrow, in what part the Cerebel is hanged to it, viz. nigh the lesser annulary process; from whence it is immediately carried with a double process into the hole of the stony Bone: one of its branches is harder, serving chiefly for motion, the other altogether medullary and softer, as it were only destinated to sense.

A little lower arises the wandring pair, which is commonly called the sixth. This seems to be made of many Nerves, many of which arise together; and to them comes another, endued with a greater trunk, which being brought from the end of the ob­long Marrow, yea beyond this, out of the spinal Marrow, is united with the former. And so all being made like a bundle of Nerves, go out through the hole of the hinder part of the Head; through which also goes out the greater branch of the internal ju­gular Vein. This is by us called the eighth pair.

Under the wandring pair, almost out of the Basis of the oblong Marrow, another pair arises, consisting also of many Fibres, which going straight down, and being presently immersed in the dura Mater, comes forth again through a peculiar hole out of the Skull; then either Nerve, being inoculated into the trunk of the wandring pair, is presently bended back towards the Tongue. In a man, a peculiar protube­rance grows above the oblong Marrow, out of which the beginning of this Nerve proceeds. This we call the ninth pair.

Below this, in the lowest part of the hinder part of the Head, out of the sides of the oblong Marrow, where it is about to go into the spinal, another pair, consisting also of many Fibres, arises; which tending towards the spinal Marrow, enters the dura Mater at the same place where the vertebral Artery ascends into the Brain; yet it arises out of the bosoms of the bones, but below the first Vertebra or Joynt, from whence it is carried into the Muscles of the hinder part of the Neck, so that it is doubt­ful, whether this pair ought to be called the last of the Skull, or the first of the Vertebrals.

When these parts, viz. the aforesaid Nerves and Arteries, both the Carotides and the Vertebrals, with the jugular Veins (by which the Encephalon is fastned to the foot or basis of the Skull) are cut off, and their ends stretched out as much as may be; either let them remain in the taken out substance or frame, whereby the be­ginnings of all the Nerves may be plainly noted; or the trunks of them being cut off near the roots, may be left in the holes of the Skull, whereby their goings out and distributions may be observed. The images of either Example are delineated in the first and second Table.

The business of Dissection being thus far brought, the residue of the Skull shews many things worthy consideration, of which we shall speak particularly afterwards. But first we ought to view throughly the taken out frame or substance of the Brain, together with its Appendix, and to examine all its appearances as they follow in the order of Dissection.

The substance or bulk being taken out, which is of a somewhat round figure or spherical, it exhibits to the sight in its superiour and convex part the Brain and Ce­rebel; but the oblong Marrow, with the utmost borders or edges of the superiour bodies, possesses almost all the basis or its lowest part. The thinner Meninx covers these three placed near, and the outward superficies of them all; nor doth it clothe the same loosly, but deeply insinuating it self into all their cavities and recesses, covers and binds them strictly. And as this Membrane is every where interwoven, with the folds of the Vessels, by its stretching out, it reaches the same to every part and por­tion, and so waters the whole with a sufficient afflux of blood. Here we must consi­der the Vessels of this Membrane and its protension.

As to the former, the whole superficies of the frame of the subject may be seen, covered with the infoldings of Vessels, as it were with a net admirably variegated or flourished, and its sight or aspect shews like the picture of a fruit-bearing wood; the Idea of which, the Vessels of the Brain more aptly represent, and are themselves seen better and more distinctly, if you first squirt into the Carotidick Artery some black li­quor. The Vessels interwoven within the thin Meninge or Pia Mater are Arteries and Veins. The Arteries are four, viz. two Carotides and two Vertebrals. Out of either side of the Tunnel the ends of the cut off Carotidick Arteries shew themselves, the trunks of which ascending upwards, are presently diffused from either side into the anterior and posterior, or fore and hinder branch. Either pair of these inclining one towards the other, are mutually conjoyned: moreover, the posterior branches so joyned, are united with the Vertebral branches (growing together first into one trunk.) For the Vertebral Arteries, arising from the last hole but one of the Skull, fall at first di­vided through the sides of the oblong Marrow; then united in its basis, they go into a single chanel, which meeting with the hinder branches of the Carotides, (as it is said) it is joyned with them; and from that place of the joyning of them together, a noted branch ascends on either side under the edge or rim of the Brain, which be­ing dilated upon the shanks or stocks of the oblong Marrow, is cleft or divided into very many small shoots like hairs, some of which ascend to the Glandula's placed behind the Cerebel, but the rest make the arterious part of the Choroeidal infoldings. The anterior branches of the Carotides, before they are united, send from themselves on either side a noted branch, which creeping upwards like a bounding River, distin­guishes either Hemisphere of the Brain as it were into two Provinces; but after the aforesaid branches are united, presently departing again from one another, they are carried to the Prow of the Brain, and from thence bending back between its Hemi­spheres, they fall upon the callous body. All these Arteries, before and after their mutual joyning together, send forth shoots and little branches on every side, which do not only creep through and intimately bind about the utmost compass of its Sphere, but its Penetralia and more inward recesses, like the young branches of Vines. The ramifications or these sorts of branchings, both of the Carotides and of the Vertebrals, are shewn in the first Table, as they are found in a Man, and as in a Sheep in the se­cond Table.

Moreover, this thinner Meninx or Pia Mater cloathing the whole Brain and its parts, as it receives the Arteries ascending (as hath been said) from a fourfold Fountain, so it is stuffed throughout with Veins, sent from four bosoms. These Vessels mutually meeting are complicated together, and almost every where constitute by their branches derived from both, and meeting one the other, and variously contorted among them­selves, the net-like or retiform infoldings; which indeed are not only outwardly in the superficies, but in the diffection, where-ever you may separate one part from another, without breaking it, these kind of infoldings of the Vessels are to be found. Because, if you behold this frame, taken out of the Skull, collecting together the tops of all the turnings and the Interstitia in this Membrane, and covering them with the joynings of the Vessels, it will make the whole compass or frame of the Encephalon appear like a curious quilted ball. But if you go on to cast abroad this Sphere, and to separate the cleaving parts, knit together, of this Membrane, one from another, you will soon find, that this Meninx covers the gapings of the crevices or turning chaps of the Brain, binds the Interstitia of either moity or Hemisphere, draws together the hinder part of the Brain, otherwise being lax and hanging loose, and compassing about every border of it, as it were with a Welt, knits it to the oblong Marrow: and what is the chief of all, the universal Cortical or shelly substance of the Brain (to wit, in which the animal Spirits are procreated) is covered over with this Membrane plant­ed with most frequent infoldings of the Vessels; notwithstanding the interior super­ficies of the Brain being stretched out, (which being called the Callous body, is alto­gether medullary and white) is not cloathed with this Membrane; but instead of it many foldings of Vessels, commonly called Choroeides, are hung and as it were freely flow within its complicature. The reason of which is, because as this part, to wit, the callous body, is rather designed for the Circulation than for the generation of Spirits, therefore it admits not a more plentiful influx of blood: nevertheless, for as much as there is need of heat, whereby the Spirits may be there more easily circulated, the blood being moved, within the Vessels hanging there through the empty space, might afford heat as it were from a fire kindled within a Stove. But within all the [Page 60]other recesses of the Brain, and besides within the folds or lappets of the Cerebel, yea and the Interstitia or gaps of both these, and of the oblong Marrow, this Meninx insinuates it self, and inserts the distributions of the Vessels. In truth, the proten­sion or out-stretching of this Membrane seems therefore the more admirable, because having no where a peculiar place of its origine, it not only binds about the Head or Encephalon with a common covering, but also cloaths all its parts with proper co­verings, and knits together their tops and processes. Yea this Meninx seems to en­joy a manifold and diverse original: for where-ever the gapings or Interstitia of any parts or processes happen, portions of this Membrane there springing forth, cover them all, and gather them together, and reach to them the ramifications or branch­ings of the Vessels. In a moister Brain this Meninx may be easily separated, and ample and large portions of it pulled away with the fingers; which being drawn away, the insertions of the Vessels, into the substance of the Brain and its Appendix, every where clearly appear. Lastly, by this means the brain being thus left naked, unclothed of its Membranes and Coverings, its make or fabrick, and the disposition or order of all its parts are next subjected to Anatomical Inspection.

That the Anatomy of the Brain, properly so called, might be rightly celebrated, I judge we ought not to proceed after the common way of Dissection. But whenas the substance of the whole Head, taken out of the Skull, stands in view, first let the hinder partition of the brain, where it is knit to the Cerebel and oblong Marrow or Pith, the Membranes being every where cut or pulled off, be freed (as much as it may be) from its cleaving to the subjected parts; then it will easily appear, that the substance of the brain is not united to those bodies, but of it self is altogether free and independent of them, unless where it is joyned towards the superficies by the knitting of the Membranes. Also this keel or hinder part of the brain being divided by this means from the neighbouring parts, if the fore part be bent back, the shanks of the oblong Marrow will appear wholly naked, and distinct from the brain and Cerebel (unless where they are in some places hung to it.) Moreover, when the partition of the brain, being loosned from its cohesion, is lifted up, the three Ventricles, com­monly so called, go into one empty space or mere vacuity, resulting from the com­plication of the brain. Besides, it may be observed, how the brain before is only united to the oblong Marrow; and that in two places of its shanks, as it were the tops, it is fixed; which Fornix so called, or arched Vault, is as it were a string or ligament, which arising before, where the brain is hanging to it, is carried to its hinder border, to which it is united as it were with two stretched out arms, and so it holds together the whole frame of the brain, lest it be rolled out into a plain, still in a spherical figure, and firmly binds the same to the shanks of the oblong Marrow. From the knitting of the other parts of the humane brain divided and lifted upwards, whereby the vacuity resulting from its infolding, and esteemed for Ventricles, also whereby the Fornix or arched Vault and shanks of the oblong Marrow, naked and distinct, may be beheld, is represented by figure in the fourth Table.

And truly, this Position or Aspect of the Brain, to wit, when its hinder border or partition, being freed from its cohesion by the Membranes to the oblong Marrow, and elevated, is bent forward, exposes to be seen by the eyes themselves, its whole frame or substance, to wit, whatever it hath without or within, or before and be­hind, and also plainly detects what its habitude and respect is to the other parts. The chief things of these I shall add, and in the same order wherein they occurred to Inspection.

The figure of the Brain, especially in a man, shews somewhat globous or spherical: the outward superficies is on all sides noted with chinks turning and winding like to the rollings about of the Intestines: each breach or involution, yea the whole circuit of it contains a twofold substance, viz. the Cortical or rindy, which is the outmost and of an Ash-colour; and the medullary or marrowy, which lyes under it, and ap­pears white. The brain being as it were plowed with these kind of rollings about, like so many ridges and furrows, is cleft in the middle, and parted as it were into two Hemispheres; yet both the moities come together, and are as it were founded in one like white substance, which covers inwardly, and as it were in Chambers or Vaults, the whole bulk of the brain. This is harder than any other portion of the brain, and as it is altogether medullary, it receives all the marrows of the circumvo­lutions within it self, and is to them instead of a common basis. In either Hemisphere of the brain, about the fore parts, this callous body or marrowy substance, becomes [Page 61]more firm and thick by far than in any other place; and there it is on both sides fastned to the tops of the oblong Marrow. From those tops, as it were its beginning, this medullary substance, covering over or chambering or arching the brain, is stretched out towards the hinder parts, and by degrees lessens in its thickness: at length the outward border of this stretched out, is drawn together more narrowly, and more below, it is conjoyned by the knitting of the Membranes and Vessels (as we but now mentioned) to the tail of the oblong Marrow. Besides, for its more firm connexion, a medullary process arises from the fore part of the callous body to­wards the tops of it, which stretching under the fissure or cleft of the brain, reaches to its border; to which it is united, as it were with arms bending on either side: which arms indeed embrace the tail of the oblong Marrow, and so more firmly knit to it that border of the brain.

This medullary process, commonly called the Fornix, under its rise or beginning, hath two white and medullary roots, either of them alike going out from the callous body, which roots nigh the tops, where the brain is hung to them, meeting toge­ther, pass into the Fornix or Vault it self, as if it were a broad process, which stretches under the chamber of the brain, like a beam. Under this twofold root of the Fornix is laid cross-wise, of the same magnitude, a medullary trunk, by which, like a bridge, there is a certain passage and communication between two processes of the form of a Lentil, and chamfer'd or furrowed bodies beaming or shining in them. Further, from the midst of the superficies of this Fornix, a thin and pellucid hedge or pale is erected, which is affixed to the chanel or furrow of the callous body, almost along its whole passage. And for this reason, whilst the three-sided Fornix stretched underneath a chamber, arising from the complication of the brain, it distinguished its appearing cavity as it were into three partitions, and so caused, that in it three Ventricles were represented.

The interior recesses of the Brain will lye yet more clearly open, if the border, being on every side separated and lifted up, as much as may be, from its cohering with the oblong Marrow, be cut a little further through the substance at the sides of the same Marrow, to which it is united, nigh the chamfer'd bodies, and also the Fornix, being cut nigh the roots, be bent back, together with the brain; for then the frame of the brain may be wholly lifted up, turned forward, and unfolded into a plain, so that the whole interior superficies of the callous body being stretched out into a broad floor, may be seen and handled. Where, besides the medullary, and its most white substance, may be observed many white parallel lines, which cut the par­tition of the brain in right angles, as if they were certain tracts or footsteps, in which the animal Spirits travel from one Hemisphere of the brain to the other, and return back again.

After this manner, in very many perfect four-footed Beasts, the frame or substance of the brain was wont to be turned over, the Sphere being projected into a plain, and its interior superficies to be unfolded into breadth. Also this kind of Method of Dissection may be used in a mans brain, where the same Phaenomena wholly occur to Anatomical observation. The chief difference is, that the bulk of the brain of a man, for that it is very large, and also far thicker, and endued with more turnings and windings; therefore it cannot be so easily and throughly inverted, as that of a Calf or Sheep, and reduced into a broad plain: yet it may be so far expanded and lifted up near its border or partition, that all the interior recesses may appear in view. The third and fourth Figures shew the image of an humane brain bent back: but in the seventh Table is shewn the aspect or sight of a Sheeps brain wholly unfolded, and as it were spread plain.

In the lesser four-footed Beasts, as a Mouse, an Hare, Coney, and some others, the superficies of the brain being wholly plain or even, wants the turnings and wind­ings; however from the complication of the border, and the under-stretching of the Fornix, there results a cavity representing Ventricles.

After that we have throughly viewed all things which belong to the Brain, in the order as we have said, let either Hemisphere, covered within with the callous body, by which it hangs, be divided and removed from the tops of the oblong Marrow: which indeed may be exactly done, by cutting it near to the sides of the Lentiform prominencies, which are found in the vulgar dissection of the Head, within the inte­rior Ventricles: for those prominences are the tops or heights of the shanks of the oblong Marrow, to which the callous body is immediately fixed. When the brain [Page 62]is cut after this manner, that the prominencies, which are the tops of the shanks of the oblong Marrow, may be left naked, let them be cut long-ways through the midst (to wit, in the medullary part, where they are conjoyned to the callous body) and their interior substance will appear through the whole chamfered or streaked; viz. medullary streaks or chamferings are seen to ascend and descend forward and back­ward; that none may doubt, but that these chamferings or streaks were made by Nature, as it were passages or chanels for the passage and return, or going to and fro of the Spirits out of the callous body into the oblong Marrow, and on the con­trary. The Figure of the shanks of the oblong Marrow, divided from the Brain, with their tops, which are the chamfered bodies, is expressed in the eighth Table.

After these striated or streaked bodies, the shanks of the oblong Marrow being divided for a little space, go forward, then being united, they meet together in the same stock, made up as it were of two stems. But the stock or trunk of the oblong Marrow in its whole tract, viz. before and after the coalition of its shanks, hath many Processes, Appendices, Prominences, and Infertions of Vessels, some of which arise from one side, and others from the other side, and make it unequal, with va­rious productions and protuberances; of which hereafter.

CHAP. II.

HAving described both the Meninges, and the ramifications of the Vessels in them, also the fabrick of the Brain, properly so called; and next shewed its outward partition gathered together into folds about the shanks of the ob­long Marrow, and either middle or marrowy part of it hung to the chamfered bodies; we will now follow the remaining parts of the Head in order.

The chamfered or streaked bodies, or the tops of the oblong Marrow, are two lentiform Prominences, which are beheld within the former Ventricles of the Brain, as they are commonly termed; the heads of these, which are more large and blunt, incline mutually one to another, and are almost contiguous. Out of the angle of this inclination the Fornix arises with a double root; to which is subjected or underlaid a certain transverse medullary process, and seems to knit together these streaked bo­dies, as may be seen in the seventh Table GG: but the ends of those bodies, being made sharper, are reflected outward, and make as it were two sides, with a sharp triangle, to whose anterior superficies the marrow of the callous body sticks for a long tract; where, if these bodies be cut long-ways through the midst, the medullary streaks (as was already said) will presently appear. The figure and place of these, as also the medullary chamferings, are truly represented in the eighth Table.

Where the streaked bodies end, the chambers or Thalami, as they are termed, of the optick Nerves, possess the next part to the oblong marrow; to wit, in this place, [Page 64]its shanks rise into unequal protuberances, out of the ridges of which the Optick Nerves arise, and from thence, being bent down in the fore-part with a certain com­pass, they joyn together about the base of the same marrow, and seem to be united; by and by being again parted, and going forward towards the ball of the Eye, they go out of the Skull. In this place the shanks of the oblong marrow in a Man are for the most part distinct, and gaping one from another, leave a descending opening, which is the passage to the Tunnel; but in most four-footed Beasts the shanks of the same medullary stocks are there distinct, only a little lower, and have a chink cut for the Tunnel: but the ridges of them, in which the beginnings of the Optick Nerves lye hid, are somewhat conjoyned, and for the space of half an inch do grow together. Wherefore in Brutes there is one hole before this growing together, and another be­hind it, both which lead towards the Tunnel. The reason of this difference is, be­cause in a Man, for that the frame or substance of the brain it self is very large, and that its marrowy parts are remote one from another, it is behoveful for its shanks, whereby the tops of the oblong marrow may be the better fitted to the same, to be separated, and from their mutual touching to be bent into a greater aperture. Hence it is observed, that in a Man the shanks of the oblong marrow, from the hanging on of the brain, go forward with a greater angle of inclination, and with a certain bend­ing compass; but in Brutes the same lye almost parallel. After what manner these parts are sormed in an humane brain the third and fourth Figure shews; after what manner they are in four footed Beasts is shewn in the seventh Figure.

From the same ridges of the medullary shanks, from whence the Optick Nerves take their origines, certain medullary processes arising, and being dilated on either side above the brim of the second hole, grow together about the root of the pineal Glandula. These processes (as it seems) are those parts, which the Famous Cartes supposes to be Nerves belonging to the pineal Glandula: but I rather suspect them to be productions only, by which the Optick Nerves may also communicate near their origines. Their figure is very well described in the seventh Table.

After the Thalami or Chambers of the Optick Nerves, other notable protuberances, commonly called Nates and Testes, the Buttocks and Testicles (of the brain) grow to the superior part of the medullary Trunk or stem, and cover its superficies about the space of an inch; and for that they are not contiguous in the midst, there is under them a certain hollowness in their whole tract. These protuberances are lesser in a Man, also in a Dog and Cat; lastly, if we observed rightly, in other living Crea­tures, which are newly brought forth, that are impotent, and not instructed for the finding out of sood. In a Calf, Sheep, Hog, and the like, they appear far greater: in Fishes and Fowls they are wholly wanting.

In number they are four, viz. two grow to either side of the oblong marrow. The former called Nates or the Buttocks, seem the greater and principal; to which the other latter called Testes or the Testicles, hang as if growing out of them. As to their figure, they are round, and are commonly taken for two shanks on either side of the brain and Cerebel planted near, which being bent inwardly, and turned back one towards the other, are said to grow together, and so to constitute the oblong marrow. But this opinion, as we shall shew more largely hereafter, by the dissection ordered according to our Method, is clearly false. For it plainly appears, that the brain is fixed, long before these bodies, to the oblong marrow; nor is there any commerce between these and that, unless very remote.

But if the site of these parts, and their respects and habitudes to the neighbouring bodies, be well noted, it will appear plainly, that they make as it were a certain peculiar Region wholly distinct from the Brain and Cerebel, also from the oblong marrow it self. Their situation is remote enough from the fore-parts, and sufficient­ly separated by the Cavity or Ventricle under-lying from the medullary stock or stem: yea a proper way, or one process, seems to lead from the long marrow into these prominences, and another to go from them, and thence to be carried into the Cerebel. From hence we may suspect, that these prominences (especially the Nati­form, or of the shape of a Buttock, which are the chief) are certain places of diver­sion, in which the animal Spirits go apart in their passage from the oblong marrow into the Cerebel, and from this to that on the other side, and there stay for some animal uses, of which we shall speak hereafter. As to the way, which leads from the oblong marrow into these prominences; it is manifest, that beneath the origines of the Optick Nerves on either side a medullary Process descends, with little Villages [Page 65]proper for it self, which terminates in the aforesaid prominencies. Then, if from these, you look for a passage out, it is equally clear, that from the hindermost pro­minences, which are called Testes, on either side, a medullary process doth obliquely ascend, which being dilated into the Cerebel, is divaricated through its whole frame. But that the Natiform or Buttock-formed Prominences are Principals, and the Testes their dependences, or the heads of medullary Processes, which are carried from thence into the Cerebel, manifestly appears in a Sheep, Calf, or Horse, and in some others, where the Nates are of a noted magnitude, the Testes of a very small bulk grow to them, and in the middle between these the medullary Processes, the Appendices of the former Prominences, exist. The aforesaid Prominences, as also the medullary Processes, which lead forward and backward, to and from them, are aptly repre­sented in the fourth Table, but yet more clearly in the eighth Table TT. PP.

Further, because the animal Spirits residing in either Promptuary and Appendix, be­fore they are carried to the Brain, ought to be confounded and mingled together, there­fore the two prominences of either side do mutually grow together as it were with wings stretched out one to another; but for as much as it is behoveful for those grow­ings together to be distingushed from the oblong marrow, therefore an hollowness comes between, which is by some esteemed the fourth Belly, and by others a passage to it. These prominences in a Man, Dog, and Cat, and some other Animals (as was above mentioned) are very small, and almost even; also they appear, as the other portion of the oblong marrow, of a white colour. In a Calf, Sheep, Horse, and many other four­footed Beasts, the former protuberances, commonly called Nates or Buttocks, are re­markably great, also outwardly they appear to be of a flesh colour, because they are cloathed with the thin Meninx or Pia Mater, which contains in it self very many Veins and Arteries; which if separated, the interior substance of those parts is of a wannish colour, and such as is not in all the oblong marrow or pith besides. But it plainly ap­pears, as in Brutes, so in Man, the hinder or posterior prominences are Epiphyses or additions of the former, and that from these additions or dependences the medullary processes ascend obliquely into the Cerebel; near which, other processes cutting those, descend direct from the Cerebel, which seem not to be inserted into the medullary Trunk, but going about it, do constitute the annulary or ringy protuberance. This annulary protuberance is greater in a Man than in any other Creature. Besides, it is observed, that where ever the superior prominence of the Buttock-form is larger, this inferior annulary is very small; and so on the contrary. Further, those medul­lary processes, ascending towards the Cerebel, communicate mutually among them­selves by the other transverse medullary process; and out of this transverse process, two small little Nerves arise, the fourth pair of those which we have recounted, and which are called by us Pathetical. Each of these, delineated in fit figures, the se­venth Table shews clear enough.

Not sar from the aforesaid Prominences, to wit, between these and the Chink, which is called the Anus or Arse-hole, the Pineal Glandula or Kernel is placed. This is put in a Valley, which lyes between the Natiform protuberances, and those which are the Chambers or Thalami of the Optick Nerves; in which place that Glandula or Ker­nel is fixed, sometimes by very many small Fibres, and sometimes by two noted me­dullary roots subjected to the part; and besides, it is included in a Membrane, which is a portion of the Pia Mater, as in a Chest; and as this Membrane is stuffed with very many Arteries and Veins, some small Vessels also enter into this Glandula.

Under the Prominences but now described, (as was above hinted) a narrow Ca­vity or Ventricle is stretched out with a long passage, which, although it obtains some egregious uses, yet it self seems to be only secondary, and as it were by chance; for that the processes of either prominence ought to be conjoyned among themselves, and to be distinguished from the under lying medullary Trunk. Two holes lye open into this Trunk, one of which is placed in the beginning, and the other in the end of it, and through the middle of its passage the down-bending aperture tends towards the Tunnel; so that the serous humor entring at either hole, may presently slide away into the Tunnel. Moreover, into the same aperture of the Tunnel there lyes open another passage, to wit, through the first hole, which is placed near the roots of the Fornix; so that from every quarter of the Head the serosities might be carried into that sink: to wit, that through the first hole, from the infoldings or the anterior Ventricles of the Brain; through the second hole, the humors which are gathered about the orbicular prominences, do come away; and through the third hole, those [Page 66]which are laid up nigh the confines of the Cerebel, do find a passage. These several holes, with the distinct ways to the Tunnel, are plainly delineated in the seventh Table H. M. T.

Above the Pineal Kernel, as it were above the Button, the infolding of the Cho­roeides seems to be hung; now this infolding is made after this manner: out of either side of the oblong marrow, where the border of the brain is knit to it, two Arteries arising from the posterior branches of the Carotides, where they are united to the Ver­tebrals, do directly ascend; which being presently divided, like many Rivers planted near together, are carried towards the pineal Glandula, and there seem to be termi­nated by a mutual meeting: and in that place, out of the fourth bosom, sent down upon the pineal Glandula, the veinous branches come out on both sides, which in like manner being divided into filaments or small threads, meet with the capillary or hairy Arteries, and are in many places inoculated into them, and variously com­plicated with them; and so these Vessels, being Net-like, much interwoven among themselves, and interserted with the Glandula's, do constitute the to be admired in­foldings. These kind of infoldings of the Vessels, as it were with two out stretched wings, are thrust out on either side upon the shanks of the oblong marrow, even to the streaked bodies; but yet they only lye upon their superficies, nor are they more firmly affixed either to the oblong marrow, or to the callous body by any insertions of the Vessels; so that the blood seems only to be brought to these places, and carried away without any afflux of it made into the subjected parts; for what uses shall be spoken of hereafter. The Choroidal infoldings, with the pineal Glandula, are drawn out in the seventh Table G. F. E.

And thus far concerning the appearances sound above the oblong Marrow, between the streaked bodies and the Cerebel; which indeed are almost constantly after a like manner both in Man and four-footed Beasts, unless that they only differ in bigness. Within this space, in the Pedestal or Basis of the same Marrow, many things worth noting occur: For besides the ends of the cut off Vessels, which are above recited, the site and structure of the Infundible or Tunnel deserve consideration. For behind the coalition or joyning together of either Optick Nerve between the shanks of the oblong marrow there gaping, is sent down a receptacle as it were tubulated or made like a Pipe, covered without with a thin Membrane arising from the Pia Mater, and defended within with a medullary substance. The orisice of this is placed higher be­tween the shanks of the oblong marrow, and receives their bending aperture; from thence a short Tube or Pipe being sent down, is inserted to the pituitary Glandula or Kernel. We see this Tube in an Horses brain greater than a Gooses quill, also shi­ning and full of clear water; that it is not to be doubted, but that by this way the serous humors slide away from the brain to the pituitary Glandula: but how these humors are carried away from thence, shall be afterwards inquired into, because they are not carried into the Palate or roof of the mouth, as is commonly believed.

Nigh the lower border of the Tunnel, in a Man, underneath there are two whitish Glandula's; though in Brutes only one, but greater, is found. What is the proper use of this part shall be told hereafter: in the mean time, whether it be doubled or only one larger, it seems to be as it were instead of a bank to defend or preserve the thin Membrane of the Tunnel, lest it should be broken or thrust out of its place: on the other side the growing together of the Optick Nerves serves instead of the same kind of defence.

What besides is contained in this space are only the shanks of the oblong marrow it self, which proceed directly from the chambers of the Optick Nerves towards the hinder part of the Head in a straight passage; and when both grow together below the Tunnel, they are afterwards distinguished in their whole tract by a line drawn through the midst. These shanks of a mans brain are far larger than in brute beasts: to wit, in that they seem to be made up of very many medullary chords or strings joyned to­gether in one, as if in this common passage and high-way of the animal Spirits, they were so many distinct paths, which the Spirits enter into respectively, according to the various impulses of sense and local motion. Moreover, this space of the oblong marrow therefore appears shorter and more broken in a man, because much of it is hid by the annulary protuberance, which is sent from the Cerebel, and is very big. The Pia Mater, all about covering the sides of this medullary Trunk, cloaths them with most thick infoldings of the Vessels; by which heat and the nervous juyce are carried, as a continual provision for the Spirits, taking a long journey. Thus much [Page 67]for the first Section, or anterior portion of the oblong marrow: now our order car­ries us to the inspection of its hinder Region, to wit, where the Cerebel grows to it; and the Processes sent from this either compass about its Trunk, or are inserted into it; out of which also, the other Nerves produced within the Skull, take their be­ginnings. Concerning these we will speak in order.

CHAP. III.

BElow the orbicular Prominences, the Cerebel follows to be inspected. The figure of this, like the Brain, is somewhat globous, also it appears unequal, marked with certain turnings and windings about; the ridges and furrows of whose turnings about the Pia Mater stretches over, and reaches out the infoldings of the Vessels to them all, and deeply inserts them into all. However the Cerebel is diversisied or variegated with its turnings and rollings about, not as the Brain, after an uncertain manner; but its folds are disposed in a certain orderly series; for the exterior frame of it seems to consist of thin lappets, or little rings or circles, being contiguous and infolded, also going about through the whole compass with a parallel site or situation.

Either Region of the Cerebel, to wit, the former and the hinder, is terminated in a process in form of a Worm. According to these ends, as it were in a double Pole, these Circles are very short; thence ascending towards the top or Equator, they are by degrees enlarged, as it were Parallels in a Sphere or Globe. These Circles are out­wardly Cortical or barky, and within medullary, and all their marrowy parts pass into two ample middles; which indeed seem to be the same in the Cerebel, as the callous body in the brain.

The Cerebel in some Animals consists of one frame, and all its little circles are placed in the same parallel site, and keep the same proportion among themselves; but in others there grow to the Cerebel as it were the primary Sphere, and endued with greater circles, some other bodies as it were Wens or Extuberances, or additio­nal Spheres marked with lesser circles. These being eccentrick to the Cerebel it self, have oftentimes labels or folds ordered in a diverse series from it.

But the Cerebel it self (whether it hath these little Excrescences growing to it or not) is found almost in all Animals of the same figure and proportion, also made up of the same kind of labels or lappets. Those which have the brain diversly framed from a Mans, as Fowl and Fishes, also among four-legged Creatures, Conies and Mice, whose brains want turnings about or convolutions, have the like species and the like disposition of the folds and composure of the other parts of the Cerebel. The reason of this difference in the brain, and of the conformity in the Cerebel, is rendred hereafter, when we treat of the Use of the Parts.

As the Brain, within its Cavity, hath the Choroidal infolding made up of Arteries and Veins variously complicated, and of Glandula's thickly interserted; so also the Cerebel hath got the like infoldings of Vessels, and those marked with very many Glandula's, and greater than those in the Choroidal infolding. These infoldings and heap of Kernels, the Pia Mater being separated, which clothes the hinder part of the Cerebel, easily appear in sight; for in that place these creep upwards on either side nigh the Worm-shaped process, as it were with two branches; and receive the Artery on either side, from the Vertebral Artery, lying under the Basis of the oblong mar­row and the veinous passages, sent from either lateral bosom. We shall inquire here­after into the use of this Infolding and of its Glandula's.

In the mean time, that we may describe the site and hanging on of the Cerebel; the same standing on the oblong marrow seems to be fixed to its sides, as it were by two little feet; between which, planted on either side, and the Cerebel placed above, and the trunk of the long marrow below, (because all these should be distinct one from the other) there comes a cavity or hollowness between, which is commonly called the four Bellies.

In either little foot, sustaining the Brain, are found three distinct medullary Pro­cesses. The first of these, sent from the orbicular Protuberances, ascends obliquely; the second descending straight from the Cerebel, and passing through the other across, compasses about the oblong marrow; the third process, descending from the hinder Region of the Cerebel, is inserted into the oblong marrow, and increases its trunk as it were with an additional cord or string. These several Processes are truly repre­sented in the seventh Table Q. P. R.

But as to what belongs to the annular or ringy Protuberance, by which the medul­lary Trunk, both in Man, and in some four-footed Beasts, is compassed about, that is made after this manner. The second or middle process of the Cerebel, descending straight to the oblong marrow, seems not to be implanted in it, assoon as it touches its sides, but growing into a larger bulk, goes about the superficies of the same marrow with divers circular Fibres. And so when in either side both those kind of processes of the Cerebel, being dilated or carried from the top of the medullary Trunk toward its Basis, do mutually meet, they make that circular protuberance. The substance of this is far larger in a Man than in any other Animal; in an Hare, Rabbet, Mouse, and the like, it is very small; in Fowl it is either wholly wanting, or for its smalness scarce to be discerned by the eyes. Concerning its bulk, this is a con­stant observation. They who have the orbicular prominences before the Cerebel small, have this annulary protuberance very big; and on the contrary, they who have those prominences big or very great, have this ring very small: further, they who wholly want the Buttock-form protuberances, as in Fowl, seem also to want this annulary.

In many brute Animals, but not in Man, nigh to this greater Protuberance, a lit­tle lower, another lesser, in like manner orbicular, stands, and compasseth about the superficies of the oblong marrow; the root of which is a white and medullary line, stretched out under the Cerebel, above the bottom of the fourth Ventricle. From the sides of this lesser protuberance the auditory Nerves arise: In Man the audi­tory or hearing Nerves are seen to arise out of the utmost brim of the greater protu­berance, in like manner they have for their root a white medullary line covering the fourth Ventricle.

That this line, and the three distinct medullary Processes, which constitute either little foot of the Cerebel, may be more plainly shewn, also that the most inward frame of the Cerebel may be viewed, its whole globe ought to be cut through both Poles, viz. in the middle through the Vermiform or Worm-shaped processes; then it will plainly appear, that in either Hemisphere there is an ample middle or mar­row, wherein the marrowy branches, being stretched abroad on every side, like those of a tree, spread through the Cortical substance of the Cerebel, every where diffused; and that in either middle or marrowy part, the three distinct processes, which make either trunk, or little foot of the Cerebel, are inserted. Each of these are fitly represented in the seventh Table.

Thus much for the Cerebel, and by what means it is fastned to the oblong marrow, Beside these, it is to be observed, that about the bottom of the Basis of the oblong marrow, out of the greater Ring, come out two medullary strings, which being di­stinct from the rest of the medullary Trunk, go right forward towards the spinal marrow, and in its progress, being made straiter by degrees, like Pyramids, after about the space of an inch, end in sharp points. The extremities of these consist on the other side, where the wandring pair of Nerves have their orignal, and make a certain rising up in the oblong marrow. Hence it is likely, that these strings are passages or chanels of the animal Spirits, wherein they are carried from the greater Ring, or what is the same thing, from the Cerebel into the wandring pair, and the beginnings of other Nerves implanted near; for what end, shall be said hereafter. These pyramidal Bodies do not so manifestly appear so long as the Pia Mater clothes them, and hides them with the infoldings of the Vessels; but this Membrane being pulled away, they are so conspicuous, especially in a Man and a Dog, that they seem like greater Nerves. In those Animals, where the annulary Protuberance is greater, these processes being brought from the same in right angles, are greater and more conspicuous; and on the contrary, in Fowl they are clearly wanting.

Concerning this hinder Region of the Head, there is not much besides worth no­ting, except the productions of the Vessels. But there are Vessels which chiefly be­long to these parts, the latter six pair of Nerves arising within the Skull and the Ver­tebral [Page] [Page]

[Page 69]Arteries. We have already described in some measure the beginnings of the former; what belongs to the more full knowledge of them, we shall leave to be handled in its proper place. As to the Vertebral Arteries, they reach from about the farthest end of the oblong marrow, now about to end in the spinal, to its sides. These Vessels, as they are smaller, so they enter the Skull with lesser provision than the Carotides; for they are neither flourished first with Net-like infoldings, nor are carried in a long journey by compassing about; but either Artery, passing directly through the Cuniform or Wedge-like Bone, embraces the medullary Trunk on either side. Although these go forward divided for a little space, yet afterwards they are united, and with a single chanel or passage, they meet with the posterior Carotides inclining mutually one towards the other; and so all the branches, meeting as it were in a threefold way, are inoculated one in another. The Vertebral Arteries, first shewing themselves within the Skull, are disposed otherwise in Brutes than in men: in the latter they fall through the sides of the oblong marrow parallel for some space, then as it were with a certain semicircular compass, they mutually incline one to­wards the other, and presently meet. The branches which first go forwards divided, are sometimes only two, to wit, one on either side, sometimes three, and then be­sides the two former, another is produced in the middle. But in Brutes, either Trunk of the Vertebral Artery, at the first coming to the marrow, inclines presently to the meeting of the other with an acute angle, and quickly both meet together. The Vertebrals, even as the Carotides, send forth manifold branches in their progress with an innumerable series of shoots, which cover over the oblong marrow, the Ce­rebel, and all their cavities and recesses, and water them all with a plentiful flood of blood.

These are the Phaenomena or Appearances which the whole frame of the Brain and its Appendix is wont to exhibit Anatomical Inspection, and which, as to its fa­brick, and all its parts, and processes, are to be found both within and without. As it is a hard and troublesom business to inquire into the actions and use of each of these, so it is also joyned with so much pleasure and profit, that I dare promise to my self and others, that it will be a thing worth our labour and while. Yet before we enter upon this, there remain to be unfolded some things hid in some of the bones of the Skull, such as are the pituitary Kernels, the admirable Net, and some others; also we ought to shew first, briefly at least, a type or figure of the Brains in Fowl and Fishes.

CHAP. IV.

IT is not our intent, nor will it be needful for us to delineate the figures and situa­tion of the several Bones of the Brain-pan, or to describe their various holes, which transmit the Trunks of the Vessels like the hanging weights of a Clock. All these are well enough known; so that to treat of these Gates or Entries is superfluous. Besides also, by what means the Nerves, arising within the Skull with their ramifi­cation or branching forth, enter the dens and caverns of the Bones, shall be delivered particularly afterwards. Wherefore for the present our business shall be only to take notice of some things, chiefly worth noting, concerning the sanguiferous Vessels passing through the Cuniform or Wedge-like Bone, not sufficiently noted by others.

Among the various uses and offices which the Cuniform or Wedge-like Bone yields to the Brain and its Appendix, it is not of the least note or moment, that it transmits the Carotidick Arteries, not without a certain mechanical or artificial provision; and that in the middle way, by which they must pass, it contains the pituitary Kernel, and sometimes the wonderful Net. Each of these deserve consideration; the more, for that in divers Animals they are after a different manner; and because it is much controverted among Physicians concerning their frame and use. But we will first speak of the pituitary Glandula, because this part, being placed higher, is observa­ble to Anatomical Inspection before others.

The pituitary Glandula or snotty Kernel is hid within a proper Cell or stall, made hollow in the middle of the Wedge-like Bone, being shut up in the Chest sometimes [Page]

[Page] [Page 71]more strictly, sometimes more loosly: For in a Dog, Cat, and some other Creatures, stick­ing to the Tunnel, it is pulled away together with it when it is removed; and then its bulk consists of two Glandula's or Kernels distinct among themselves, and easily to be separated one from another. But in a Calf, Sheep, Hog, and many others, it is strictly included on every side, except where it admits the Tunnel, and clothed with the hard Meninx or dura Mater, and with its coverings shut up between the cavity of the bone. Besides, in these, its frame or substance seems but one and undivided, though, in truth, it is made up of a substance which is of a twofold nature or kind.

This Glandula is found in all perfect Creatures; for Man, all four-footed Beasts, yea Fowl and Fishes are provided or endued with it: from whence we may conclude it to have some necessary uses in the Brain. But as to its quantity or bigness, its proportion is various in divers Animals, according to the bigness of the head and body wherein it is; because in a Lamb it is greater than in a Man or a Dog; also its bulk in a Horse is lesser than in an Ox. But the reason of this difference seems to consist in this chiefly, for that the pituitary Glandula in some, respects the bulk of the brain only laid upon it, and in others both the brain and the Carotidick Arteries ascending near it; and so as it hath a respect to both these together, or only to one, its substance or bulk is ei­ther greater or lesser. For truly in some Animals the Carotidick Arteries being di­lated within the Skull, are presently divaricated into Net-like infoldings, and from those infoldings many shoots of the Vessels every where enter this Glandula, and are interwoven into its substance. Further, because this infolding of the Vessels, called the wonderful Net, is found very large in some, and in others very small; therefore this Kernel, for as much as it admits from these, few branches, and from those far more, and in some other Animals scarce any shoots from the Arteries, answers to this divers distributions of the Vessels, with the various proportion of its bulk. Be­cause it is observed in some Animals, as chiefly in a Man and a Horse, that this wonder­ful Net is wholly wanting; and whereas in such, either Artery is carried about by a long compass between the recesses of this bone; from its trunk in a man sometimes one or two shoots, sometimes none, are carried into the pituitary Kernel; also in an Horse fewre branches enter into it, and so its bulk in these becomes lesser.

But in very many other Animals (especially those who have the wonderful Net) it may be proved, besides ocular inspection, also by this Experiment, that many san­guiferous Vessels enter this Glandula: for if an inky liquor be squirted into the Caroti­des with a Syringe, the exterior part of the Glandula, that is interwoven with the blood­carrying Vessels, will be very much dyed with a black colour. Wherefore without doubt, it may be thought, that this Glandula doth receive into it self the humors, to wit, flowing into it from the Tunnel in all kind of living Creatures, and in some from the branches of the Carotides. Yet by which way these humors are carried away again, doth not so plainly appear; for we affirm, with the most Learned Schneider, that they do not at all fall down into the Palate through the holes of the under-lying bone. Yet in the mean time, we suppose those holes to be only made to procure lightness to the bone; because in those Animals, which have the greater pituitary Kernel, those holes in the bone are more and larger: further, I have often found vessels or chanels to be contained between those holes: and when I had injected Ink within the great hole of the same bone in a Calf, the black liquor presently entred the lesser Vessels subject to the bone, and at last the Jugular Vein. And by this Ex­periment chiefly we conjecture concerning the office and duty of this Glandula; of which we shall speak more fully hereafter, when we inquire into the use of this and the Tunnel.

Nigh to either side of the pituitary Kernel, if the dura Mater be opened, the Ca­rotidick Artery lyes stretched out upon the wedge-like bone, about the length of an inch: for as this Artery rises up below the Turky Chair, sometimes higher, some­times farther within the Skull; the same being presently bent in from its first ascent, goes in under the dura Mater till it comes to the anterior border of the same Chair; where again being intorted, and being sent forth upwards with a certain compass, it perforates the hard Meninx, and is carried straight towards the Brain. So this Ves­sel with its double ascent and crookedness (to wit, above the Basis of the Skull, and then above the hard Meninx, together with its situation, stretcht out in length under the same) represents in most the letter [...] inversed; but in a man (as shall hereafter be more largely shewn) its site, by reason of the longer tract of the Vessel and its greater curvature, represents the same letter double after this manner [...].

The Carotidick Artery in all Animals ascends obliquely within the Skull; but as to its site or protension nigh the pituitary Glandula, it is not after the same manner in all: for in a man passing through the Canal-bone, peculiarly ingraven by it, with a single Trunk, it lyes every where stretched out at length; and out of this Trunk it sends forth sometimes, though not always, some shoots to the pituitary Glandula. Also in a Horse, its Trunk is single; but where it first arises within the Skull, either Carotides, through the cross branches sent from one side to the other, before they perforate the dura Mater, communicate among themselves. And as in most other living Creatures, the Artery, however before branched forth, yet being made one sin­gle Trunk, goes into the Brain; in a Horse either Carotick Artery being parted in two, sends forth upwards two branches, arising from the dura Mater, in two di­stinct places.

In a Dog, Fox, Sheep, Calf, Stag, and many other four-footed beasts, either of the Carotides, whilst hid within the Skull under the dura Mater, being divided into small shoots, and complicated with other Vessels, to wit, both Veins and nervous Fibres, constitutes the Net-like infoldings; which infoldings, being stretched out on either side of the Turky Chair, fill the cavity there existing; then after manifold divarications of all the Vessels, some arterious shoots being disintangled from the others, and again united, grow together into one Trunk, which boring thorow the dura Mater, pasles straight into the Brain.

The aforesaid Infolding is, commonly called the wonderful Net, and that deser­vedly, for there is nothing in the whole fabrick of the animal Body more worthy of admiration; in which, besides the arterious little branches which proceed from either of the ascending Carotides, the veinous shoots, though fewer, meet with those de­scending from the inward Jugular branches; and both kinds of Vessels being divided into small shoots, like a bundle of twisted silk, are variously folded together: which complications of the Vessels however are sustained by the nervous Fibres, supplied from the greater Trunk of the fifth pair of Nerves. The aforesaid infolding of the Vessels or wonderful Net in some Animals is far greater, and contains much more di­varications of the Vessels than it hath in others; for in a Calf, Sheep, Goat, which are fed with grass, its frame is larger than in a Dog, Cat, and other flesh-eating and hotter Brutes. Further, it is observable, where the wonderful Net is greater, that the infolding of one side is ingrafted into the infolding of the other opposite side, and that from both, many more shoots of the Vessels do enter into the pituitary Ker­nel; so indeed, that if you shall inject Ink into the Trunk of the Artery below the Skull, the Vessels on either side, or the infoldings, will be dyed with the same tincture, and the black liquor will flow out of the Trunk of the opposite Artery.

In truth we have often seen this kind of Experiment repeated. Let the Carotidick Arteries be laid bare on either side of the Cervix or the hinder part of the Head, so that their little Tubes or Pipes, about half an inch long, may be exhibited together to the sight; then let a dyed liquor, and contained in a large Squirt or Pipe, be inject­ed upwards in the trunk of one side: after once or twice injecting, you shall see the tincture or dyed liquor to descend from the other side by the trunk of the opposite Artery: yea, if the same be more copiously injected towards the Head, from thence returning through the Artery of the opposite side, it will go thorow below the Prae­cordia, even to the lower Region of the Body; when in the mean time, little or no­thing of the same tincture is carried thorow the outward and greater Jugular Veins. Then the Head being opened, all the Arteries, before the entrance of the Head, and the Veins of the same band with them, will be imbued with the colour of the same injected liquor. Further, in the Vessels which constitute the wonderful Net, and which cover the Basis of the Brain, some footsteps of the same tincture will appear. But that this liquor doth descend so plentifully by the opposite Artery, and not by the Jugular Vein, either associate or opposite, the reason is, because it cannot enter those Veins, unless the region of the whole Brain, being first passed thorow, it had entred the bosom; but the liquor being plentifully injected, could not so suddenly pass through the very small Vessels covering the Brain: wherefore rather than the force should be carried to the Brain by the violent impulse of the liquor, it, return­ing from the injection, and otherwise threatning a flood to the Brain, finds the way of receding also by the opposite Arteries, for that end, both before they enter the Brain, and after they have entred it, communicating among themselves. And here we cannot sufficiently admire so provident (and to be equalled by no mechanical Art) [Page] [Page]

[Page 73]a dispensation of the blood within the confines of the Brain. For in as much as the Carotidick Arteries do communicate between themselves in various places, and are mutually ingrafted; from thence a double benefit results, though of a contrary effect: because by this one and the same means care is taken, both lest the brain should be defrauded of its due watring of the blood, and also lest it should be over­whelmed by the too impetuous flowing of the swelling stream or torrent. As to the first, lest that should happen, one of the Carotides perhaps being obstructed, the other might supply the provision of both; then, lest the blood rushing with too full a tor­rent, should drown the chanels and little Ponds of the brain, the flood is chastised or hindred by an opposite Emissary, as it were a Flood-gate, and so is commanded to return its flood, and haste backward by the same ways, and to run back with an ebbing Tide.

By this kind of provision the Arteries about to enter the Brain are provided: yea, and the passages of the Veins, destinated for the returning of the blood from thence, seem also to be disposed with a wonderful artifice. For when the anterior bosoms transfer their load into the two Laterals, which are the posterior, and they them­selves end in the Jugular Veins, it is observed, that those latter bosoms have furrows or cavities insculped whereby they may settle or rest upon the hinder part of the Head: and whenas either bosom, through a proper hole, being about to go into the Jugular Vein, slides out of the Skull; nigh that hole, in the outward part of the Skull, a round and ample den is made hollow, and covered over by the extremity on either side of the same bosom, inlarged into a greater capacity, to the end, that the blood, whilst it slides forth out of the Head with a full torrent, should not rush into the Veins with too rapid and vertiginous an influx, and so make a forcible entry on the Heart it self, therefore it hath here a diversion large enough, in which estuating or boiling up, till a more free and open space may be granted to its course, it may be staid with­out any trouble. Certainly there can be nothing more artificial thought upon, and that can better argue the Providence of the great Creator, than this fit or convenient disposition of the blood in the brain, and without it, and the way of its reciprocation in divers Animals, accommodated to the necessity of every one. And lastly, in the dissection of Beasts, other miracles of the same nature happen, whereby shewing the finger and Divine workmanship of the Deity, a most strong and invincible Argu­ment may be opposed to the most perverse Atheist.

CHAP. V.

WHat hitherto we have shewn concerning the description of the Brain and its Appendix, we chiefly owe to the observations made of the dissection of the Heads of a Man and of four-footed Beasts. We shall now proceed to the commenting upon these Observations; to wit, that we may endeavour, from the fabrick rightly considered of the parts of the Brain, so described, to erect their offices and uses, and so to design the government of the animal Function: But because a compared Anatomy may yield us a more full and exact Physiology of the Use of Parts; therefore before I enter upon this task, it will seem worth our labour to in­quire into the Heads of some other Animals, to wit, of Fowls and Fishes.

We have already hinted, that the Brains of Men and of four-footed Beasts, were alike in most things; and also that the contents in the Heads of Fowls and Fishes being far different from both the former, yet as to the chief parts of the Head, are found to have between themselves an agreement. The kinds of either Animals being coetaneous, and as it were Twins from the Creation of the World, do testifie their affinity in nothing more than in the fabrick of the Brain. That it is so in Man and four-footed Beasts plainly appears already: we shall now see if that the Anatomy of Fowls and Fishes will shew us any thing worthy of note.

That we may begin with Fowls; the covering of the Skull being taken off, the hard Meninx or Membrane embraces strictly the bulk or mole contained within. In the midst of it, where the brain is divided into two Hemispheres, it hath a bosom stretched out at length, which notwithstanding, no Falx (or Scythe) being let down between the interstices, is inserted less deeply in the brain: then, where this Mem­brane distinguishes between the brain and the Cerebel, two lateral bosoms are for­med. Besides, in Fowls there is a fourth bosom, which hath its place a little more backward than in a man or four-footed beasts; for a little below the pineal Kernel a hollow and smooth process of the hard Meninx is sent down upon the shanks of the oblong marrow, where presently it is divided into two branches, on either side where­of it sends forth one upwards into the cavity between the streaked Membrane and [Page]

[Page] [Page 75]the Hemisphere of the brain, planted in the hinder part of the brain.

This superior Membrane or hard Meninx being cut off, and separated round about the Pia Mater, appears very thin, which is not, as in man or other perfect Crea­tures, marked with such frequent infoldings of the Vessels; but this most subtil Me­ninx being made of a texture of Fibres, only clothes, and every where intimately binds about the even and plain superficies of the brain contained within, and wholly destitute of turnings and windings about.

The fabrick of the brain in Fowls is otherwise than in man or four-footed beasts: for besides that in its compass the inequalities and the turnings and windings are wholly wanting; also more inwardly, the callous body and the Fornix, as also the chamfered bodies, which we described before, are all lacking: and besides, the sub­stance of the brain it self is figured after another manner. That these may the bet­ter be beheld, make the dissection of the brain of a Goose or a Turky-Cock; and the Membranes being cut off, by pressing lightly the fissure or cleft of the brain, you may divide the middle of it one from another, and go forward to separate it, till you come to its bosom, in which place are two marrowy bodies, which being stretched out like Nerves, connect the Hemispheres one to another. Either side of the Inter­stitium or the space between, is clothed with a whitish Membrane, which is marked with streaks or beams, lying or running from the whole compass or circumference, to the lower corner; and these streaks concenter about the insertions of the medul­lary bodies. Then, if this Membrane be cut, in either Hemisphere of the brain, there will appear underneath a cavity, which goes under the whole space, from the side of the Interstitium, and for a great part, the hinder region of the brain, and is arched or chambered with that streaked Membrane. Either cavity or hollowness, about the bottom, is opened into an intermediate or common passage, which lies open to the Tunnel; and from either side of this passage the shanks of the oblong marrow are stretched out, to which, on either side, the Hemisphere of the brain is hung by two medullary bodies; to wit, one marrowy or medullary body goes out from the mole or substance of the brain lying under the Ventricle, the other from the streaked Mem­brane covering the Ventricle. From these two, placed on either side, the medullary bodies being stretched out cross-wise, like Nerves, joyn the two Hemispheres of the brain to one another. Besides, these two growing together on either side, fix either Hemisphere of the brain to the shanks of the oblong marrow.

So the figure of the Brain in Fowl, if you compare it with the brain in men and of the more perfect four-footed beasts, seems to be as it were inversed. For as in these the Cortical part is outward, and the medullary laid under it; so in Fowls, the lower frame of the brain, which consists of a thick and closer substance, is instead of the Cortex or shell; but the outmost and upper Membrane, chambering the Ventricle, appears medullar or marrowy above any other part. Moreover, the Ventricles in the brains of a man and four-footed beasts are placed beneath, and near the bottom; in Fowls, above and nigh the outward border. The reason of this difference seems to be, because in a more perfect brain, such as is in man and four footed beasts, the animal Spirits have both their birth and exercise; viz. they are procreated in its Cortical or shelly part, and in its medullary, which being large enough, lyes under this, they are circulated and variously expanded for the acting of their faculties. But truly in the brain of Fowls there is space enough for the generation of Spirits, but for their circulation there is scarce any left: to wit, the brains of Birds seem not to be much possessed with the gifts of phantasie or memory: yea it is thought, that the Spirits begotten in the brain are exercised chiefly in the oblong marrow for the pre­serving the animal function; for there, as we shall shew anon, the medullary sub­stance, which is instead of the callous body, consists; and like the streaked bodies in others, in these are streaked Membranes, through which the Spirits, procreated in the brain, are carried, without any order there, forthwith into the oblong mar­row: but because the Spirits, begot in the brain, ought to lay aside a serous excre­ment; therefore the Ventricles, from the complicature of the streaked Membrane upon the keel or lower part of the brain, and on the shanks of the oblong marrow it self, do serve conveniently enough for this business. Notwithstanding, because in the brains of Fowls, the Fornix is wholly wanting, there are only two anterior Ven­tricles; between which, the Choroeides infolding is stretched out; the veinous portion whereof, as was but now said, arises a little lower from the fourth bosom; but the Arteries ascending, come from either side of the oblong marrow.

Nor is there a greater heterogeneity or difference of conformation in the Brain it self of Fowls, than in the oblong marrow from the same in men and four-footed beasts. For in the first Section, from whence the Optick Nerves arise, two noted protuberances grow to either side. These are much greater in proportion than the orbicular prominences in the more perfect Creatures; so that they seem another additional brain: either of them of a white colour, and purely marrowy, is hollow within; so that in these kind of Animals are found two bellies or Ventricles in the brain, and as many in the oblong marrow. And seeing in these, as in all other Ani­mals, a cavity is put under the Cerebel, the Ventricles in the whole Head differ as well in number as in figure and position.

In the middle of the medullary Trunk, to wit, where those prominences grow to its sides, the Chink, leading to the Tunnel, is cut, but into it the aperture of either Ventricle gapes or opens, that it is not to be doubted, but that the serosities heaped up there, are sent out by that way. Moreover it is likely, that these hollow and me­dullary prominences in Fowls supply the course of the callous body, to wit, in which the animal Spirits are circulated for the exercising their faculties: because in the brain the space is so narrow, that the Spirits cannot be produced and circulated together within its confines. Further, as in Fowls, the use of the animal Spirits is required for the act of the sensitive and loco-motive faculty, more than for phantasie or me­mory; certainly the chief place where they may meet and be exercised, ought to be placed rather in the oblong marrow than in the brain.

The Carotidick Arteries, which carry the blood to the brains of the greater Birds, are so small, that there is no proportion of these to the same in man and four-footed beasts. Their Trunks being carried within the Skull, ascend without any branchings into net-like infoldings, alter the same manner as in other Animals, nigh to the pi­tuitary Glandula, and pass right into the brain, and distribute some small shoots of the Vessels both to its exterior compass, and through its inward recesses. But in truth, the brains of Birds are watered with a very small portion of blood, in respect of other living Creatures; because, where the fancy or imagination is little exerci­sed, there is not much blood required for the refreshing the animal Spirits.

Fowl (otherwise than some affirm) have both the mammillary processes, and the Cribrous or Sieve-like bone. For the anterior productions of the brain being highly extenuated and involved with the dura Mater, stretching out almost to the middle part of the bill, are inserted into the triangular bone, which hath a double bosom, distinguished between with a thin mound or pale. But these processes being dilated within the bosom of the aforesaid bone, and in Bladders full of clear water, which are very like the mammillary processes in a Calf, full of clear water. Besides, as out of the fifth pair of Nerves, a noted branch on either side passing through the ball of the Eye, enters into the cavern of the Nostril, a shoot of it being sent out of the Trunk, is bestowed to the very orifice of the Nostrils; in the mean time, both the greater Trunks, compassing about the Cribrous bone, meet together, and presently going one from the other, and being carried to the end of the bill, are distributed into the palate. After this manner Fowls, even as men and four-footed beasts, are furnished with a peculiar organ of smelling, to wit, with a double mammillary pro­cess; and besides, they have within the Nostrils additional Nerves out of the fifth pair, by whose action and communication of branches into other parts, and among themselves, so strict an affinity is contracted between the smell and the taste. The other pairs of Nerves are almost after the same manner as in men and four-footed beasts. In like manner we also observe, that there is no great difference as to the Cerebel and the other portion of the oblong marrow, between Birds and the other Animals we have already considered on, unless that the orbicular prominences before the Cerebel, and the other annulary under it, meeting within them, are both wanting in Fowls; indeed these latter seem not at all to be required; but instead of the for­mer, they are easily supplied from the hollow medullary prominences, such as we have shewn to be in Fowls.

And these are what are chiefly worth noting to be found in the brains of Fowls. We have already mentioned, that there is a certain likeness between these and Fishes as to the most parts of the head: wherefore it will seem to be to the purpose, that here for a conclusion we should say something of the brain of Fishes. First, we shall observe, that as the heads of Fishes, in respect of the whole body, are greater than of any other living Creatures, yet they contain in them less brain than others. For [Page 77]two little moles or substances, placed before, sustain the whole place of the brain, properly so called; out of these, two signal smelling Nerves proceed, which are car­ried by a long and straight journey to the holes made hollow, out of either side of the mouth, and which are instead of nostrils: and this is singular to Fishes. Moreover, we advertise concerning the Optick Nerves, that they, as in other living Creatures, inclining mutually one to the other, are not however united, unless perhaps towards the superficies; but they are crossed, and a Nerve arising from the right side of the oblong marrow, is carried into the left Eye, and so on the contrary: so indeed, that the visory rays have their refraction, not only in the Eye, but within the very bodies of the Nerves. The oblong marrow in Fishes, wholly after the like manner as in Birds, hath two signal protuberances hollowed within; and in truth, as to local motions, the Spirits in either seem to the exercised after the like mode. For as Fishes swim in the water, so the flying of Fowls or Birds seems a certain kind of swim­ming in the Air. Further, in these 'tis observable, there are the pituitary Kernel, the Tunnel, and the Carotidick Arteries as in other Animals; also many pairs of the Nerves have the same origines and distributions, excepting that the hearing Nerves are here wanting; although Casserus Placentinus attributes this gift to the smelling Nerves. The figure of the Cerebel is the same as in more perfect Animals. Besides, what we have remarked concerning the wandring pair of Nerves in man and four-foot­ed beasts; to wit, many fibres of it arising together, the trunk of the Nerve from the spinal marrow comes to them: in like manner the same is in Fishes. But to describe them all further is needless: for the rest, as those which are proper to them only and Birds, as also those which they have common with Fowls and the more perfect Animals, may be easily known, partly out of the peculiar similitude with birds, and partly out of the universal Analogy of all. Therefore we will now philosophise upon the Use and Action of the Brain and its Parts, and of its Appendix, together with the whole oeconomy of the animal Function: where in the first place, we will inquire into the offices of a more perfect Brain, such as of man and four-footed beasts; and also secondarily and collaterally we shall explain the Offices and Actions of a less per­fect Brain, and of its Parts, such as that of Fowls and Fishes.

CHAP. VI.

THE Poets feigned Pallas to be formed within the Brain of Jupiter, and from thence to be born. In truth, within the Womb of the Brain all the Concepti­ons, Ideas, Forces, and Powers whatsoever both of the Rational and Sensitive Soul are framed; and having there gotten a species and form, are produced into act. Wherefore it will be worth our labour to inquire into these places, of the generation of these more noble faculties, and the first rise and primitive beginnings of them, as also more curiously to consider the divers parts of the Brain, or the Organs serving to their Generation: And I go about this part of my labour the more willingly, that I may by handling the thread of our dissection again, bring all the Phaenomena, before given to our inspection and sense, before the Eye of Reason, and to be again weigh­ed by a more severe Examination of Discourse; at least those things which seem to be of the greater moment, and chiefly worth taking notice of. Neither do we think here to heap up into a great Volume the several things worn out by the handling of others, and offered to common observation.

Therefore recollecting the Anatomy of the Brain, the first things to be considered are its coverings, to wit, the Skull, and the two Meninxes or Maters. Concerning the first it is observed, that all perfect Animals have an hard and bony Skull. A dou­ble reason for which may be given: First, that the Head being destinated for the most noble use, might be protected with a more firm and not easily penetrable covering, as a natural Helmet, against the injuries of external strokes; besides secondly, as this is in the place of Armor, so also of a Cloister; because the same covering the dura Mater within, may restrain and keep within the Brain the Effluvia's of the ani­mal [Page 78]Spirits, lest they should too thickly evaporate, or in heaps. Further, as the Skull for these ends is made bony, the efficient cause are the saline Particles of the blood watering the brain, which being unprofitable to the interior work of the ani­mal Spirits, and so to be sent away outwardly, grow together thus in the circumfe­rence, and are congealed into a stony hardness: For indeed the blood being carried towards the Head, as it abounds very much in Spirit, so in Salt; its Particles highly volatile, being joyned to the Spirits, are bestowed on the brain; in the mean time, the saline little bodies, which are of a more fixed nature, being thrust out into the circumference, from the Spirit implanted in the Brain, constitute the stony Skull, as it were a bubble covering inclosed wind.

Within the hollow superficies of the Skull, there appear many furrows and inequa­lities imprinted by the protuberances of the Vessels; and we perceive frequently either border or plate of it to be perforated by the passing through of the Vessels in several places: but the Arteries, arising in the exterior superficies of the dura Mater, make these kind of little ditches through the concavity of the Skull. For when the whole substance of the brain is at first soft, and easily giving place, like Wax; the Arteries underneath it continually beating, as it hardens by degrees, easily imprint the marks of their tracts.

The figure of the Skull in four footed beasts is narrow and prest down, but in man, the substance of whose brain is large, there is required a more capacious and al­most spherical figure. For as God gave him an upright countenance to behold the Heavens, and also endued his brain with an immortal Soul, and fitted for the specu­lation of Heaven; therefore his face is erect or lifted up: so the brain it self is placed in a more eminent place, to wit, above the Cerebel and all the Sensories. But in Brutes, and such whose faces are prone towards the Earth, and have a brain unfit for speculation, the Cerebel, however serving to the more noted action and office of the Praecordia, is placed in the highest seat to which the mole of the brain is subjected. Besides, some organs of the Senses, to wit, the Ears and Eyes, if they be not superior, they are placed at least equal to the brain. In an humane Head, the Basis of the Brain and Cerebel being placed nigh together, yea of the whole Skull, is made parallel to the Horizon; whereby it comes to pass, that there is less danger for any portion of the Head to be jogged here and there, or to be moved out of its proper seat: But in four-footed beasts, who go with an hanging down head, the Basis of the Skull makes a right angle with the Horizon; wherefore the brain being subjected, the Ce­rebel is put in the highest place; so indeed, that this seems less stable, and that it may shake, or be moved from its seat. However against this inconvenience, lest a frequent concussion of the Cerebel might induce a sinking down or loss of the Spirits, or irregularities about the Praecordia, in some it is taken care of by a wonderful arti­fice of Nature; for as in all the frame or substance of the Cerebel is most strictly bound fast together by the dura Mater, besides in some it is staid by a bony fence; but in others, as in a Hare, Rabbet, and other lesser Brutes, a certain portion of the Cerebel is included on either side by a stony bone, and so by this double hold its whole bulk or substance is firmly tyed to the Skull. Concerning the chief bones of the Skull, viz: the Cuniform or Wedge-like bone, the Cribrous or Sieve-like bone, and the auditory or hearing Organ, they shall be spoken of in their proper places, when we come to treat particularly of the Ventricles of the Brain, and of the Senses to which these bones serve. We shall pass next to the hard Meninx or dura Mater.

The dura Mater or hard Meninx, formed of a double kind of Vessels and Processes, bears also a double Aspect, and owes part of its office to the Skull, that is about it, and part to the Encephalon contained within it. The exterior processes of this Mem­brane are insinuated within all the bosoms and cavities of the Skull; to some whereof they are a covering and defence, but to others they impart a sensible force; which manifestly appears in the Sieve-like bone, through whose holes the fringes of this Membrane passing, conduce something to the sense of smelling. Also the productions of this, lying over the recesses and caverns of the Wedge-like bone, fortifie the ways for the entrance and coming out of the Vessels. The interior processes of the dura Mater, which belong to the Head, divide and distinguish between the parts of the brain and Cerebel; and in those places the dura Mater is very thick, lest in any great concussion of the Head, these two should be smitten one against another, and should press one upon the other. Wherefore in Dogs (as we have already hinted) who are wont to run violently with their heads down, there is sent down between these [Page 79]bodies a bony fence. In like manner in a Cat, Horse, Fox, and many other Ani­mals, from whose manner of living and use it is required, that they be moved with a swift motion, that bony fence, commonly called the Triangular Bone, is sent down deeply between the Brain and the Cerebel; yea, and all the bosoms pass through that bone in the holes curiously made hollow in it.

The Vessels belonging to the dura Mater are either Arteries, that carry the blood thither; or they are Veins, which receiving from thence the superfluous blood, and from the whole Head besides, return it towards the Heart. As to the first sort of Vessels, on either side, two Arteries arising from the Carotidick Artery on the same side, before it comes to the Basis of the Brain, are carried into the dura Mater: which notwithstanding, only possessing the exterior superficies or convex part, carry blood and juyce to this Membrane, also in some measure to the Skull and its cove­rings. As to the Vessels carrying the blood back, this Meninx contains four, into which, as into a great Sea, all the Rivulets of the Arteries, serving the whole Head, do exonerate themselves: to wit, there are observed in this Membrane four noted Cavities, commonly called Bosoms; which are disposed after that manner, that, like Promptuaries or Store-houses framed in several places, they receive the blood return­ing from every region and corner of the brain: For the third bosom, or the longitudi­nal, looks towards the anterior brain, the fourth towards its middle; but the first and second admit the blood flowing back from the Cerebel and hinder part of the brain. Further, out of these the third and fourth disburden themselves into the first and second; and these at length transfer their burden into the Jugular Veins. On every side, from these bosoms, the lesser Vessels, viz. the chanels of the Veins are sent forth, which going out night the interior or concave superficies of the dura Mater, are presently inserted into the Pia Mater, and following its protension, being distri­buted through the whole compass, and all the interior recesses of the brain and its Appendix within the Skull, and being complicated with the Arteries, receive the superfluous blood, and carry it into those greater cavities. That it is so, it plainly appears, because if you squirt a liquor, dyed with ink, into the Pipe of the Artery, that passing through the arterious shoots, and then the veinous, goes through at last into the bosoms.

Whilst the blood, returning from the whole interior Head, is collected within those bosoms, as with a full belly, it seems also in another respect to be of a very notable use; to wit, for the supplying of heat, requisite for the distilling forth of the animal Spirits, as if it were a certain Chymical operation. For as much as the blood to be distilled, is contained in the Vessels, interwoven into the Pia Mater, the supe­riour Rivers diffused on every side through the dura Mater, the heat being brought to it like a Balneum Mariae, flow about the underlying blood, and so force out of it a most subtil Liquor into the substance of the Brain; or rather, the blood raising up heat within the bosoms, is like the fire of suppression, which in the distillation by descent, is inkindled round about the Vessel containing the matter to be distilled. For indeed the interior substance of the Brain, for that it is endued with plenty of Salt and very little Sulphur, is of a more frigid temper: wherefore, that from the blood watering its superficies, the spirituous part may be stilled forth, and forced into its middle or marrow, the degree of the ambient heat ought to be made the more strong, such indeed, as the blood collected in the ample Estuaries of the bosoms, may easily afford. Further, as those bosoms being distended with heated blood, are like a certain distillatory Bath; so the other Membrane of the dura Mater being stretched out about the whole Head, is like an impervious Alembick, which with its covering keeps within the spirituous breaths, that they may not be immoderately evaporated.

Concerning this Membrane there may yet be considered, with what motion or sense it is endued. And as to sense, 'tis not to be doubted, but that it hath it ex­quisitely: For since all the Membranes have feeling, and owe that faculty to the afflux of the animal Spirits from the Brain, surely this Meninx, for that it is nearer and very much of kin to the Brain and its Appendix, so that it clothes very many Nerves going out of the Skull, it obtains a very accurate virtue of feeling: which thing also may be argued from the effect; because the pains of the Head often proceed from the breach of unity excited in this Membrane. But that it hath motion, it can hard­ly be thought, because it is tyed in very many places to the Skull; and yet it is pro­bable, that the same may sometimes, in some parts at least, be contracted and wring­led [Page 80]or drawn together: And certainly there is no doubt, that it is contracted and remitted in sneeling. In like manner, when from an hurt of this a Vomiting or Con­vulsive motions follow in the Viscera or Members, this Membrane is the cause, which being somewhere contracted or divided, infolds with it self the substance contained within with the same Convulsion or Spasm.

Concerning the motion of this Membrane, a curious mind may yet further consider its texture, and especially how it is within the cavities of the bosoms, and the Inter­stitium or separation of the Brain and Cerebel. For in these places are found many Fibres, or as it were greater or nervous cords or strings, such as we have observed to be variously stretched out in the Ventricles of the Heart. Within the bosoms, from the various processes of the Membrane, a cavity full of turnings and windings, and manifoldly divided, as it were with many little Cells, is constituted. This seems to be thus made, to this end, to wit, that the blood returning back from divers little rivers into the cavities of the bosoms, may be retarded by several obstacles, as it were little flood-gates; lest perhaps rushing too impetuously and by heaps, it might flow within this Sea with a vertiginous and inordinate motion. But there is observed, besides these intrications and little cells of this Meninx in the heads of four-footed beasts, that moreover in the whole cavity of the bosoms, very many cords, as it were Ligaments, are every where produced from one side to the other. The office of these is partly, that they may contain the sides of the cavity within their due ends of aperture and dilation, lest they should be distended above measure by the vehement rushing in of the blood, and so may press upon the substance of the brain. Yea the contexture of these whitish Fibres, which are met with, both within the cavities of the bosoms, and in this Meninx, going about the Cerebel, and distinguishing be­tween it and the Brain, seems to intimate, that they serve also to some motion. For it may be suspected, that those strong Fibres, and as it were Ligaments, do some­times contract, sometimes dilate, and variously draw the Membrane to which they are knit. From these kind of motions of the dura Mater, the blood flowing within the bosoms, may be variously agitated, and as occasion serves, sometimes hastened in its Circle, and sometimes restrained or hindred; for in many affections of the sensitive Soul, the blood being disturbed from its equal circulation, is sometimes precipitated by heaps and impetuously to the Heart, and sometimes detained from its nest longer, nigh the confines of the Brain. But that various whirlwinds of pas­sions stir up such irregularities in the motion of the blood, the nervous parts im­planted about the Praecordia, are in some measure the cause, which by contracting or dilating the same, variously moderate the course of the blood; yet so, that in the mean time, some part of this office is due from the brain it self, or at least to its Appendix. Indeed the brain it self wants motion; but the blood passing through its substance, for as much as it is poured wholly in this Meninx, and passes through its receptacles, is at the motion and beck of this Membrane, sometimes driven away from the brain, and commanded to succour the Heart, as in fear and great sadness, sometimes being hastened towards the brain, is for some time prohibited from flow­ing back, as in shame, indignation, and some other affections.

Truly, that these kind of interior processes of the bosoms, and as it were trans­verse strings or cords, do conduce to the more commodious reduction of the blood, we gather also from hence, that in working beasts, whose brain (because they feed and go with a prone and hanging down head) is in greater danger of an inundation of the blood, those processes are very big, for that they being successively contracted, may leisurely thrust out the blood, apt otherwise to stagnate by reason of the incli­nation of the head. Neither is it from the purpose to observe here, that these same Animals are always furnished, for that reason, with a greater wonderful Net: by which means indeed it is provided, that the blood may not too much invade the brain by heaps; as care is taken by the artifice but now described, lest the same should make too long stay in the brain, and so oppress its more weak frame.

Therefore in the last place, that I may recollect what I have said of the dura Mater, and rehearse its chief uses: First, It covers over the Skull within, and reaches to it some­what of nourishment by the Vessels. Secondly, It is a covering to the whole head, and serves to distinguish its chief parts. Thirdly, It contains the Vessels designed for the reducing the blood from the whole interior head; which, in the mean time, by reason of the plenty of the blood contained in them, and the opportunity of their situa­tion, administer requisite heat for the distillation of the Spirits. Fourthly, It pro­vides [Page 81]ways for the admission and going out of all the Vessels within the Skull, and fortifies them; to which may be added, that it bestows on some of them their Coats, as shall be shewn anon. Fifthly and lastly, This Meninx being here and there contracted or divided by the animal Spirits variously moved, according to the passions of the Soul, or the necessities of Nature, stays the blood sometimes longer near the confines of the Brain, sometimes drives it forward from thence towards the Praecordia.

CHAP. VII.

THE interior Meninx or Pia Mater is far thinner than the exterior, and consists of a most subtle contexture of Fibres. This does not compass about the Encephalon's superficies as loosly as the Dura Mater; but embraces it so very strictly, that it is very hardly separated from it: besides, it insinuates it self into all its turnings and windings and furrows, and clothes their inward parts. Further, this Meninx, although it be thin, yet being covered over throughout with the in­foldings of Arteries and Veins, is interwoven with them, and so waters all the spaces of the Brain and Cerebel with innumerable rivers. For as the Region of either of these, especially of the Brain, is full of turnings and windings, this Membrane in like manner grows to the deep furrows of the crankling turnings about, and also to the tops of the ridges; yea, the chief complications of the Vessels are still placed in the vallies, as if they were there hid in regard of their safety. Neither doth this Meninx only cover the gapings of the turnings and windings about; but also ga­thers together the tops or heights of all their interstices or places between, and knits them together, and so makes the whole superficies of the Head plain, globous, and as it were like the World.

That the diffusion of this wonderful Membrane into all the turnings and windings of the Brain, and the distribution of the Vessels through those most intimate recesses, may be the better beheld; let the head of a man, or of a brute beast that dyed of the Dropsie, be opened: For in such, whose brain abounds with much moisture, the little stays, whereby this Meninx is fixed to the substance of the brain, are loosned, so that the Membrane, with the infoldings of the Vessels, may be easily drawn away, and pulled off almost whole: which indeed being pulled off, the folds of the brain will appear naked; also the insertions of the Vessels every where into the more in­ward substance of the brain, may be perceived. But to a sound and dry brain the Pia Mater sticks so closely, that it can scarce be drawn away in any part, or separated with a Penknife.

We have already shewn after what manner the Veins and Arteries (which creeping like Ivy, are knit into the Pia Mater, and variously interwoven into it) cover over with most thick little shoots, the whole compass of the Brain and Cerebel, and their Interstices, the gapings of the crankling turnings and windings about, bosoms, and cavities, and send forth every where small shoots into the medullary substance; so that it is not to be doubted, but that the animal Spirits, being as it were stilled forth immediately from the blood, every where in the whole head, are received into the Pores and passages of the Brain and Cerebel. From hence it will be easie to assign the use or office of the Pia Mater: viz. First, this Membrane clothes the universal parts of the whole Encephalon, and distinguishes them all one from another. For indeed, this lying over all the gapings and interstices of the turnings and windings, is instead of a mound or fence, by which the animal Spirits are restrained every where within their proper cells and orbs of expansion, nor are they permitted by this means to run beyond their bounds, and so confound the acts of the many Faculties. Then se­condly, this Meninx sustains all the blood carrying Vessels, viz. both the Arteries and Veins, together with their manifold productions, and so affords a passage to the blood, by carrying it to and fro towards the brain.

Concerning these Vessels, which are knit to this Meninx, and follow its stretching [Page 82]out into all parts, there are many admirable things to be met with, and highly worthy of note, the uses and reasons of which is our purpose to search into.

As to these, we shall first observe, that these Arteries and Veins, otherwise than in any other part of the body besides, not arising nigh one another go forth as com­panions, but going forth from opposite ends, meet every where mutually, viz. the Arteries ascend from the Basis of the Skull, and by creeping through the whole, emit upwards shoots and branches, which are met by the Pipes of the Veins arising out of the bosoms, and carried downwards. By this means the rivers of the blood seem to be made equal every where in the Brain, viz. whilst the smaller shoots of the Veins follow or match the greater branches of the Arteries, and on the contrary, the small branches of the Arteries the Trunks of the Veins.

Secondly, We have already shewn, that these Vessels are variously and very much ingrafted or inoculated among themselves, not only the Arteries with the Veins, but what is more rare and singular, Arteries with Arteries; to wit, the Ca­rotidick Arteries of one side, in many places, are united with the Carotides of the other side; besides the Vertebrals of either side among themselves, and are also in­oculated into the posterior branches of the Carotides before united. The joynings together of the Carotides, in most living Creatures, are made about the Basis of the Skull under the Dura Mater, and that after a diverse manner; in some communica­ted through the Vessels of the wonderful Net from one side to the other; in others (as in a Horse we have observed with a certain admiration) the arterious chanel is produced between the Trunks of the Carotides, whereby the blood may be carried from one side to the other, and so on the contrary. But besides, between the Dura Mater, about the Basis of the Head, the same kind of ingraftings of the Arteries are still seen in man and all perfect four-footed beasts.

The reason of these seems to be partly, that the blood to be carried from the Heart into divers Regions of the Brain, might be exactly mingled as to its parts and particles, before it come to the place designed. For the Torrent of the blood, because divided into lesser rivulets, is incident to languish in so long a circuit, and its Spirits to be depauperated, and lastly it self to grow cool; unless that various courses of its Latex should anew inkindle this vital flame about to be extinguished or dye.

But there is another reason far greater than this of these manifold ingraftings of the Vessels, to wit, that there may be a manifold way, and that more certain, for the blood about to go into divers Regions of the Brain, laid open for each; so that if by chance one or two should be stopt, there might easily be sound another passage instead of them: as for example, if the Carotides of one side should be obstructed, then the Vessels of the other side might provide for either Province. Also as to the Vertebral Arteries, there is the same manner of provision made. Further, if both the Carotides should be stopped, the offices of each might be supplied through the Vertebrals, and so on the other side the Carotides may supply the defects of the shut up Vertebrals.

After this manner, lest there should be wanting an afflux of the blood at any time in any part of the Brain, or its Appendix, within the Skull, there is care taken with singular Art: For as there are four distinct passages, and those remote one from the other, of this Latex, if perchance three of them should happen to be shut up, the blood being carried through one only, will soon supply or fill the chanels and passages of all the rest. Which thing I have found by Experience often tryed, not without admi­ration and great pleasure. To wit, I have squirted oftentimes into either Artery of the Carotides, a liquor dyed with Ink, and presently the branches on either side, yea and the chief shoots of the Vertebrals, have been dyed with the same tincture: yea, if such an injection be sometimes iterated by one only passage, the Vessels creep­ing into every corner and secret place of the Brain and Cerebel, will be imbued with the same colour. Also in those who have the wonderful Net, the Tincture or dyed Liquor being injected in one side, it will come through the Net like infoldings of the Vessels in both sides. Hence it plainly appears, that there is a communication be­tween the Vessels watering the whole Head; and although every Artery is carried to one only Region, as its peculiar Province, and provides for it apart; yet, lest that any part should be deprived of the influence of the blood, more ways lye open to every part by the ingraftings of those vessels; so that if the proper vessels by chance should be wanting in their office, its defect may presently be compensated by others neighbouring.

It is not long since we dissected the dead body of a certain man, whom a great [Page 83] Scirrhus or hard Swelling within the Mesentery, growing at last ulcerous, had killed. When his Skull was opened, we beheld those things belonging to the Head, and found the right Carotides, rising within the Skull, plainly bony or rather stony, its cavity being almost wholly shut up; so that the influx of the blood being denied to this passage, it seemed wonderful, wherefore this sick person had not dyed before of an Apoplexy: which indeed he was so far from, that he enjoyed to the last moment of his life, the free exercise of his mind and animal function. For indeed, Nature had substituted a sufficient Remedy against that danger of an Apoplexy; to wit, the Vertebral Artery of the same side, in which the Carotidick was wanting, the bulk of the Pipe being enlarged, became thrice as big as both its Pipes on the other side: be­cause, the blood being excluded the Carotidick, adding it self to the wonted pro­vision of the Vertebral Artery, and flowing with a double flood into the same belly, had so dilated the chanel of that Artery above measure. This Gentleman, about the beginning of his sickness, was tormented with a cruel pain of the Head towards the left side. The cause whereof cannot be more probably assigned, than that the blood excluded from the right Carotidick Artery, when at first it rushed more impetuously in the left, had distended the Membrane; and therefore the same distemper did after­wards vanish of its own accord, to wit, the superfluous blood being derived through the Vertebral Artery.

Thirdly, Concerning these sanguiferous Vessels covering the Pia Mater, we ob­serve, that the Arteries and Veins, whilst they meet one another, going out from opposite ends, do not only transfer their burden immediately through the several branches or shoots, mutually ingrafted, as is wont to be done in other parts of the Body; but being variously complicated and interwoven, do constitute every where admirable infoldings, into which, for the most part, very small and very numerous Glandula's or Kernels are inserted. Which thing is seen, not only in the infoldings, which are called Choroeides, (by which name, besides those which are found within the plicature or folding up of the Brain, we also intend others planted together be­hind the Cerebel) but these kind of infoldings of the Vessels, with Glandula's sowed between, are seen every where to be sprinkled through the whole compass and in­terior recesses of the Brain and Cerebel, and especially between the gapings of their turnings and windings and interstices. This is clearly manifest in a moister Brain, or in an Hydropical, where the very small Glandula's, which otherwise are scarce to be seen, being intumified by the moisture, are easily beheld. Moreover, from the aforesaid infoldings, on every side implanted, little slender Vessels, being every where sent forth, enter the Cortical, and in some measure the medullary substance of the Brain and its Appendix; for if you squirt into the Carotides a black liquor, be­sides the shoots of the Vessels, which it dyes every where with the same colour, little blackish pricks will appear sprinkled in the substance of the Brain. Further, if the brain of a living Animal be cut up, the live blood will spring forth both from its Cortex and medullary part. The reason and end of all which, if they be inquired into, it seems that these foldings of the Vessels, being variously complicated with repeated windings about, as if they were little serpentine chanels hanging to an Alem­bick, through whose narrow straits the blood passing with a long circuit, becomes still more subtil and elaborated; to wit, its thicker part, being by degrees put off in its passage, or sent away by the little branches of the Veins, and so at length the only pure and most spirituous blood, and it self now ready to go into animal Spirits, is admitted within the Pores and passages of the brain. But as the blood or sangui­nolent part is supped up by the Veins, so it's very likely the Serum or watry part is received by the Glandula's or Kernels interwoven in them. For it appears not for what other end these Arteries are every where beset with so many Kernels, unless they should lay up in them the superfluous serosities. Between these infoldings there appear not any Nerves to be found, which may require any juyce or serous humor from these Kernels; and 'tis not yet found, whether these Lymphaeducts or Water-carriers be accompanied with any Vessel: wherefore it may be lawful to suppose, that whilst the purer and spirituous part of the blood, being separated from the rest of its mass, is stilled forth into the brain, the serous humidities are received by the Glan­dula's, which are numerous, and that they are for some time retained by them, till they may be sent away into the Veins growing empty again.

Thus far we have beheld only the superior branchings forth of the blood-carrying Vessels, which are every where interwoven in the Pia Mater; and their infoldings, [Page 84]which like the leaves of a Wood, or creeping Ivy, cover the exterior compass of the whole Head. But by what means, and as it were Chymical Artifice, these Vessels do instil the animal Spirits into the Brain and Cerebel, and serve for the use of one another besides, shall be told anon, after we have considered of the inferior Aspect and next the ground of this most thick Wood, viz. the greater Trunks of all the Ar­teries, which are destinated for the Brain, where they pass through the Skull, and shew themselves beyond it.

CHAP. VIII.

THE Arteries, destinated to the Brain, are four in number, viz. two Carotides, and as many Vertebrals. Concerning the former, we have already observed, that their Trunks pass through the Wedge-like Bone, as it were with a mechanical provision; to wit, either Artery is so bowed and intorted in its ascent, that the blood, before it can reach to the Brain by a repeated stopping of shores, or hindred by a certain lett or impediment, might flow to it less rapidly and more slowly. But this is not effected after one and the same manner in all Animals: for although the ascent of the Artery be oblique and intorted in all, yet in some, viz. in a Man and a Horse, it being bowed about with a greater compass, still enters, even to the Brain, with a single and undivided Trunk: when in most other beasts the same passes the Skull with a lesser circuit, and sliding presently under the Dura Mater, diversifies it self there into Retiform infoldings, commonly called the wonderful Net. There­fore it seems to be to the purpose, that we inquire into the various reasons of this difference.

In the first place therefore we shall advertise you, that the Carotidick Artery in a man enters a little more backward the Skull, than in any other Animal, viz. nigh that hole through which the lateral bosom slides out of the Skull about to be implant­ed into the Jugular Vein; for in the rest, this Artery arises within the Skull under the end or acute process of the stony Bone. But in an humane Head, the same being carried about by a longer compass, (that the Torrent of the blood, before it comes to the border of the Brain, might flow slowly and pleasantly with a broken force) at­tains to the Basis of the Skull nigh the den made by the ingress of the lateral bosom; where being presently intorted, it enters the proper Chanel insculped in the Wedg­like Bone, and for the greater assurance it is clothed besides with a thicker additional Coat. This double defence seems to be given it, lest the blood, boiling up too much, and whilst it is carried violently towards the head, should make a Whirlpool about the ingress of the Skull, to wit, where it begins to be wreathed about from its di­rect ascent, and should break by its flood the banks of the Belly, unless they were more firm. The Artery being slid out of the bony chanel, lays aside also its ascititious or additional Coat; and now being well enough defended within the Skull, goes for­ward clothed only with its proper Coat, and creeps under the Dura Mater, and being as it were depressed in the midst of its passage into a valley, being immediately carried out again, it goes on till it comes to the head of the Turky Chair; where again be­ing bent in and intorted, with a certain compass, it ascends straight, and boring through the Dura Mater, is carried towards the Brain. The Trunk of this Carotis, like a Meander, passing through the Skull with a very much bending way or passage, is aptly represented in the first Figure of the following Table.

If the reason of this kind of Conformation be inquired into, it easily occurs, that in an humane Head, where the generous Affections, and the great forces and ardors of the Souls are stirred up, the approach of the blood to the confines of the Brain, ought to be free and expeditious; and it is behoveful for its River not to run in narrow and manifoldly divided Rivulets, which would scarce drive a Mill, but always with a broad and open chanel, such as might bear a Ship under Sail. And indeed, in this [Page 85]respect, a man differs from most brute beasts, in which, the Artery being divided into a thousand little shoots, lest it should carry the blood with a fuller chanel, or more quick course than is requisite, makes the Net-like infoldings, by which indeed it comes to pass, that the blood slides into the Brain very slowly, and with a gentle and almost even stream. If that be true, as some affirm, that the wonderful Net also is sometimes found in an humane Brain, I believe it is only in those sort of men, who being of a slender wit or unmoved disposition, and destitute of all force and ardor of the mind, are little better than dull working beasts in fortitude and wisdom.

Secondly, The conformation of the Carotidick Artery in a Horse, comes nearest its structure in a man; for in this the Artery enters the Skull also lower, and with a greater compass than in other four-footed beasts: which being passed, its Trunk being intorted, with a certain compass, and then a little depressed, goes forward whole to the side of the Turky Chair still with a full and broad chanel: which truly ought to be made so, because magnanimous and fierce forces are convenient for this Animal, born as it were for War and any dangerous attempts; and so there was need, that the blood might ascend the Brain with a free and plentiful course, and (when occasion requires) with a full Torrent. But though the blood passes through the Basis of a Horses Skull in the same undivided chanel, yet it ought not to come to the Brain it self in one single passage; because the frame or substance of this in a Horse being far weaker and colder than in a man, it might be overthrown and drown­ed by the blood rushing in by heaps: wherefore the great River of the Artery disbur­dens it self by two Emissaries, and pours out its Latex at so many distinct places of the Brain. Further, as if by this means there were not yet sufficient caution against the Deluge of the Brain, a transverse or cross chanel, as it were a diversion, is for­med between the chanels of either Artery; through which the blood, being straitned for room, may go aside, and flow and reflow from one bank or chanel to another, rather than oppress or overflow the Brain. Also besides, certain shoots being sent out from the Trunk of either Artery, are inserted into the pituitary Glandula, the use of which is doubtless to separate certain serosities of the too watry blood, and to lay them up into that Glandula, whereby the rest of the bloody Latex, to be carried to the Brain, becomes more pure and free from dregs. By what means the Caroti­dick Arteries, in the head of a Horse, pass through the Basis of the Skull, is repre­sented in the second Figure of the following Table. I have not yet had the means to inspect the brains of a Lyon or a Monkey; but there is reason to suspect, that in these also the Carotides do pass through the Skull with a single Trunk. In a Sheep, Calf, Hog, yea in a Dog, Fox, Cat, and other four-footed beasts, which I have hitherto opened, this Artery is divaricated into Net-like infoldings, which Vessels, for what causes and for what uses they are so made, we shall now inquire into.

Thirdly therefore, most other four-footed beasts, different from a Man and a Horse, have the wonderful Net adjoyned to the Carotidick Artery. In truth, this is met with in so many, that common Anatomy hath ascribed it to all Animals, and also to man it self. In whom it is found, we observe, that the Artery, about to enter the Skull, is not carried about with so long a compass, but rising up nigh the hinder part of the Turkish Chair, is presently divided into small shoots; yet so, as one little chanel is stretched right out, which the blood quietly running to, passes through without any stay, being carried straight into the Brain: but from the side of this many rivulets are derived on every side, into which the blood impetuously ascending, may be easily diverted. These little rivers are partly ingrafted into the veinous passages of the same, and the Vessels of the other side, and are partly carried into the pituitary Glandula, and partly a compass being fetched, are returned into the former chanel or belly of the Artery. That it is so, besides naked inspection, appears plainly by this Experiment. If below the Skull, an inky liquor be gently and by degrees injected into the Trunk of the Carotis, that passing through the strait passage, is carried presently into the Brain, nor does it dye the lateral infolded Vessels with its tin­cture; but if this liquor be immitted continually and forcibly, presently running into the folds, it will make black the Vessels of the same and of the opposite side, also entring the hither part of the Glandula and its interior substance. If the use of these kind of infoldings of the Vessels, or the wonderful Net be inquired into, I say, that it is made chiefly for these ends: viz. First, that the Torrent of the blood being di­vided into small rivulets, its more rapid course may be so far dull'd or broken, that it may be but leisurely instilled into the Brain. For otherwise in labouring beasts, [Page 86]who go with their heads hanging down, and have but a weak brain, the more free influx of the blood might easily overthrow the fabrick of the Brain, and spoil the animal Spirits. Secondly, the divarication of the Carotides into Net-like infoldings, hath another use of no less moment, to wit, that the more watry blood being (as it is its temperament in most Beasts, and especially in those who are fed with herbage) before it be poured upon the Brain, might carry away some part of the superfluous Serum to the pituitary Glandula, and instil the other part into the branches or shoots of the Veins to be returned towards the Heart. Thirdly and lastly, for as much as the Vessels on either side are mutually inoculated by this means, there is care taken both that the blood may be exactly mixed before it ascends to the Brain, as also that more certain ways may be made for its passage: because, if perchance an obstruction should happen in one side of the wonderful Net, the blood by that infolding being presently carried to the other, may find a passage: for this cause, to wit, that the blood might be the better prevented from any impediment in its passage, the Vessels are not only inoculated under the Dura Mater about the wonderful Net, but the Arteries again on either side, do the same thing as soon as they, being knit to the Pia Mater, reach the superficies of the Brain, as hath been already shewn. By these sort of ingraftings of the Vessels in the wonderful Net, it comes to pass, that an inky liquor being injected into one of the Carotides, and forced upwards, descends by the Trunk of the Artery on the opposite side, as we have elsewhere observed. Some rude draught of the wonderful Net is expressed in the third Figure of the following Table.

CHAP. IX.

FRom the description of the Sanguiducts or Blood-carrying Vessels, which cover and weave about on every side the Pia Mater, hitherto handled, we are led by a certain thread to consider by what provision, and in what places of the Brain and its Appendix the production of the animal Spirits is performed.

1. As to the first, it appears from what hath been already said, that the blood is it self the matter out of which the animal Spirits are drawn; and that the Vessels con­taining and carrying it every where through the whole compass of the Head, are like distillatory Organs, which by circulating more exactly, and as it were subliming the blood, separate its purer and more active particles from the rest, and subtilize them, and at length insinuate those spiritualized into the Brain and its Appendix. Concerning this matter to be distilled, there is care taken, and indeed by the best means, that its stock or provision may be still supplied in fit quality and due quantity.

In respect of the quality, from the whole bloody mass, a portion highly volatile, spirituous, and endued with active Elements, ought constantly to arise towards the Head; which thing succeeds partly of its own accord, and partly that it might be more commodiously done, care is taken with a certain artificialness; to wit, the Vertebral Arteries, in all Creatures ascending straight, and almost perpendicularly, do in a manner cause, that only the more subtil and light blood is carried upwards, the remaining more thick as it were sinking down for the baser offices of the Limbs and of some of the Bowels. Yea, also the Carotides in a man, having an erected head higher than the rest of the parts, and in a Horse in some sort lifting up his face, have also the same priviledge; to wit, that by their more steep ascent only the more pure and volatile blood may ascend to the region of the Brain. But in other four­footed beasts, who go with a prone or hanging head, and who have a more frigid and watry blood, which may easily slide into, and too much wash the Brain, this evil is in some part prevented by the wonderful Net and pituitary Glandula joyned to the Carotides; which indeed receive the superfluous humidities of the blood, and so make it more pure and free from dregs before it comes to the brain.

But that the blood may be supplied still in due quantity, to wit, as it were in weight and measure, from the distillatory Vessels, stretched about the compass of the Head, there is a notable provision made in all the Carotides about the Basis of the Skull: be­cause their crooked imbowings and branching into infoldings, hinders the too great or too rapid approach of the blood: then, lest the passage of it should at any time be shut up, the mutual ingraftings of all the Vessels on either side, do help or provide for. After this manner, the business of extracting the animal Spirits is performed even as a Chymical Elixir; to wit, great care is taken in the beginning of that Ope­ration, both that choice of matter may be had, and that only a due proportion of it be exposed to distillation.

The blood by this means, as it were a Chymical work prepared, is carried by the fourfold Chariot of the Arteries to four distinct regions of the Head: and as the san­guiferous Vessels, being distributed with separate ramifications or branches through the whole compass of the Brain and its Appendix, cover all the heights of its com­passings about or [...]gyrations, and also all its crevices and their gapings and recesses, they bring to their doors the matter to be distilled into the Head every where through the whole circumference of the Brain and Cerebel nigh the Cortical substance of ei­ther; out of which as the Spirits are distilled, by this means it is brought about, that they are insinuated into the subjected substance of either. The blood being car­ried through the narrow infoldings and divarications of the Vessels, as it were (as was said) through the serpentine chanels of an Alembick is made extremely subtle, as much as may be, in its liquor; in the mean time, what is bloody is received by the little shoots of the Veins associates, or meeting one another every where, and what is serous by the Kernels every where dispersed; yet its more purified and spirituous part being carried on further through the very small shoots sent forth on all sides, are instilled more deeply into the very Pores and passages of the Brain and Cerebel; which presently flowing from the Cortical substance into the medullary, there exercise the gifts of the animal Function. What peculiar body and constitutive particles of the Brain it self and Cerebel, conduce to the generation and perfection of the animal Spirits within the substance of either, shall be shewn hereafter, when we treat of the Use of those Parts: now shall be taken notice of what we before mentioned, to wit, that the fluid extillation of the spirituous liquor from the blood about the Pia Mater, is performed after a signal manner, both from the ambient heat, which is stirred up from the blood contained within the bosoms, as it were from a Balmo Mariae, inriched by the continual flowing of it anew, and also from the obduction of the Meninges, like an Alembick, by which the spirituous Particles, apt to fly away, are constrained and forced into the parts beneath.

But indeed, though the animal Spirits are procreated wholly from the blood, yet the blood watering the Brain and its Appendix, is not only bestowed on this work: for as to the sanguiferous Vessels, which arising out of the Trunks both of the Caro­tides and the Vertebrals, cover over the whole Head and all its parts and processes; though many of them, yet not all, are little distillatory chanels of the animal Spirits. For the animal Spirits, are not produced in all places, to which these Vessels reach; for we affirm, that these Spirits are only procreated in the Brain and Cerebel: (which it were easie to prove by the Symptoms which happen in the Apoplexy and Palsie, and [Page 89]shall be afterwards clearly shewn) and from this double fountain of the animal Spirits they flow out into all the rest of the parts, and irradiate, by a constant influence, the whole nervous stock. In the mean time, the oblong marrow and its various processes and protuberances are either retreating places, or high roads for the animal Spirits, procreated in the Brain and Cerebel, and flowing from thence. But for as much as the Arteries and Veins clothe these parts also with a thick series of shoots, and that within the infolding of the Brain the folds called Choroeides are hung slack and loosly, these seem to be so made for other reasons, viz. both that these parts might be actua­ted by heat, supplied as it were from a continual fire, and also that the nourishing Juyce might be bestowed on the Spirits which flow there.

As to the first, that the animal Spirits now perfected, may be freely expanded, and irradiate the nervous System, there seems to be required, that the ambient heat, being excited by the blood flowing thither, might open all the little spaces for their passage, and notably dilate or lay open for them ways or roads: wherefore we inti­mated before, because the little shoots of the Vessels ought not to be deeply inserted into the callous body, (for that, lest the commerce of the Spirits, diverting in this Mart or meeting place, should be disturbed by the perpetual influence of the blood) therefore the infolding of the Choroeides is hung under its chamber, that at least by this nigh situation, as by a Stove or Hot-house, the heat there might be preserved. Besides, we intimated another use of this infolding; to wit, that the blood, passing through the very narrow Meanders and convolutions or rollings about of the Vessels, might lay aside its serous recrements into the Glandula's or passages of the Veins.

2. But secondly, That many branches and lesser shoots of the same Vessels which water the Brain and Cerebel, cover also the oblong marrow, and in some measure enter into its Pores and deeper substance (within which the animal Spirits are not begotten, but only exercised and expanded) I say, that this is so made for this other respect; to wit, that the substance of the oblong marrow might imbibe a constant provision of nourishment from the pouring in of the blood whereof it hath need. For whilst the animal Spirits, flowing into the nervous stock from the Brain and Cerebel, pass through this passage, as it were the high road, some food he [...]e ought to be ad­ministred to them, as it were in their journey, from the watering blood: For indeed we suppose (which also will afterwards clearly appear) that the oblong marrow, to­gether with the nervous parts, is moistned with a double humor, viz. one spirituous and highly active, which flows altogether from the Brain and Cerebel, and being from thence derived into the whole nervous stock, bestows upon them the sensitive and moving Faculties; and the other humor softer and more oily and sulphureous, which being supplied from the blood, and affused immediately on every part, is the Author of their Heat and Vegetation. Both these Juyces agree among themselves, and being every where joyned together and married, they are as it were a masculine and feminine seed mixed together; and so they impart to all parts both sense and motion, and all the powers of life and growth. Wherefore it is observed, that all the parts of the whole body, by which motion and sense are performed, do not only swell up with the animal Spirit, of whose influence being deprived, they presently suffer a resolution or loosning; but also they admit the sanguiferous Vessels; of whose Tribute if they be defrauded, presently they wither away, or are distempe­red with a mortification or Gangrene. Wherefore, that the flesh, membranes, and all the hones may be watered with the blood, (as may be perceived by the help of a Microscope) the very little or minute bodies of some of the Nerves are surrounded with Capillaments or little hairs of Arteries and Veins, together with their proper Fibrils, that we need not doubt to assert, that the Vessels penetrating the superficies of the Brain and Cerebel, do distil into them a subtil matter for the generation of the animal Spirits; but that some other shoots of the same Vessels, covering the oblong marrow, do only impart to it heat and nourishing Juyce. Lastly, that the infoldings of the Choroeides were built under the chamber of the oblong marrow, chiefly for the dispensing of heat, and in some measure for the sake of separation of the serous Latex. But concerning these, we shall have occasion to speak more largely afterwards, when we shall treat of the nutritious and nervous Juyce, and when we shall consider of that famous Controversie, viz. whether nourishment is made by the blood or Nerves: further, we shall elsewhere speak more fully of the Nature, Hypostasis, and diverse Disposition of the animal Spirits; also, what the substance of the Brain, and the con­formation of the parts, may contribute to their production.

Thus far concerning the Pia Mater and the blood-carrying Vessels, which are wo­ven in it, and following its protension, water the whole Head, we have treated largely. But before we quite leave the consideration of this Membrane, we will in­quire what sense and motion it may have. Certainly it is not undeservedly that we ascribe the most cruel Head-aches to the more acute sense of this; (in which however, by what means this Meninx is affected, does not so easily appear.) It is the common opinion, that sharp and tormenting Vapours, being raised from the Viscera of the lower Belly, especially from the Ventricle, Hypochondria, or Womb strike against this Membrane, and so pierce it with pain. But we say, though this be impossible, that Vapours passing so many interstices and bars of the Viscera and bones, without any trouble, should ever come to the Head and hurt it: yet we do not deny, but that sometimes vaporous Effluvia's do proceed from the blood boiling or estuating within the confines of the Brain, which being shut up together under the Pia Mater, and as it were gathered into a Cloud, do greatly blow up and distend it, and so distemper it with pain. I have often seen, in a Head newly opened after death, the Pia Mater distended, and shining like a Bladder, that the same seemed to be intumified, with much water included under it; which notwithstanding was found to be so done by wind distending the Membrane, for that being dissected, that Tumor fell down with­out the effusion of water.

But we think the Head-aches, which happen by reason of the evil of this Mem­brane, are chiefly excited by another means, to wit, for as much as this Meninx suf­fers a breach of the unity by the blood boiling up above measure, and rushing into its Pores and so it is contracted into lighter Convulsions. I have sometimes opened the Heads of the defunct, which when living, were obnoxious to most miserable Head­aches; in which, near the longitudinal bosom, where the feat of the pains was, the Pia Mater or interior, grew to the Dura Mater or exterior for some space, oft-times for two fingers breadth, and by their growing together had excited a sharp and un­equal Tumor; in which the mouths of the Vessels were so wholly stopped up, that there was left for the blood, though very much boiling up, no passage into the ad­joyning bosom.

As to the motion of this Membrane, we wholly deny, that it hath in it self a per­petual Systole and Diastole; however, the Pulses in some Arteries, have seemed something like it, which have given occasion perchance to this vulgar Opinion. Yet in the mean time, it may be lawful to believe, that this Meninx, for that it is very sensible, is rendred obnoxious to Cramps and convulsive motions: and that from its greater contraction the fits of the Falling-sickness do arise, and from its lesser and more partial corrugation or wrinkling together, Head-aches, as hath been said, and also sometimes Scotomies, Vertigoes, and often Convulsions of the Members and Viscera, planted at a great distance from the origine of the Nerves, being drawn into consent.

CHAP. X.

WE have thus far beheld the Coverings of the Brain, both the bony and the membranous, also the Arteries and Veins growing and knit to them, like Ivy, and distributed through the whole compass of the Head. There now remains, these coverings being removed, that we next consider the Fabrick and true Hypotype or Character of the Brain and its Appendix, together with the action and use of all the parts. And here at first sight we meet with three things, to wit, the Brain, the oblong Marrow, and the Cerebel: of which the oblong marrow seems to be a common Trunk, to which the Brain and Cerebel grow like branches: where­fore some contend the medullary Rope to be the principal part, and the Brain and Cerebel its dependences. But that it is otherwise appears by this, because these bodies, both in the generation and dispensation of the animal Spirits, are of more [Page 91]noble use than the oblong marrow; so that if the out-flowings of the Spirits from the Brain or Cerebel be shut up or hindred, the nervous System presently suffers an Eclipse; in the mean time, if this be primarily distempered, the Brain and Cerebel suffer not for its fault.

That we may begin with the Brain, it may be considered in a double respect; to wit, both as to its convex or exterior superficies, as it is beheld in its proper site and position; and as to its interior cavity, to wit, as the Brain appears opened, its concave superficies being expanded and turned upside down. We have already taken care to delineate its true form or Type in either manner, by what hath been before said, to wit, after what manner it is both within and without. There now remains, after its fabrick and conformation being rightly weighed, for us design its offices, and to shew the uses of it and of every one of its parts. Concerning which, we ought to unfold in general, first, what the office of the whole Brain is, then se­condly, when we shall descend to particulars, there will come under consideration, 1. The division of the Brain, to wit, its double Hemisphere, also the two Lobes or partitions of either. 2. The narrow crankling turnings and windings, or the gyra­tions and convolutions or rolling together of the Brain. 3. Its double substance, viz. Cortical and Medullary. 4. The common Basis of all, viz. the callous body. 5. Its subtension or Fornix. 6. The appension or circuit of the Brain over or above the ob­long marrow. 7. And what results from thence, the void space or Ventricles made by its infolding together. Concerning these, we shall take notice of what things occur worth noting; concerning the smelling Nerves and their processes, we shall inquire afterwards, when we shall speak particularly of the Nerves.

1. The Brain is accounted the chief seat of the Rational Soul in a man, and of the sensitive in brute beasts, and indeed as the chief mover in the animal Machine, it is the origine and fountain of all motions and conceptions. But some Functions do chiefly and more immediately belong to the substance of this, and others depend as it were mediately and less necessarily upon it. Among these, which of the former sort are accounted the chief, are the Imagination, Memory, and Appetite. For it seems, that the Imagination is a certain undulation or wavering of the animal Spirits, begun more inwardly in the middle of the Brain, and expanded or stretched out from thence on every side towards its circumference: on the contrary, the act of the Me­mory consists in the regurgitation or flowing back of the Spirits from the exterior compass of the Brain towards its middle. The Appetite is stirred up, for that the animal Spirits, being some-how moved about the middle of the Brain, tend from thence outwardly towards the nervous System. The rest of the Faculties of this Soul, as Sense and Motion, also the Passions and Instincts merely natural, though they depend in some measure upon the Brain, yet they are properly performed in the ob­long Marrow and Cerebel, or proceed from them.

2. In some Animals, the substance of the Brain is divided into two parts, as it were Hemispheres, distinct one from another almost through its whole thickness, even to the callous body, which is instead of a bottom; and in like manner also in all the Sensories, and in most of the other Organs of the necessary Functions, the Brain is as it were twofold, that there might be a provision made against the defect of one side by the supplement of the other. Further, in man, who hath a brain more large and capacious than other Creatures, either Hemisphere is again subdivided into two Lobes, to wit, the Anterior and the Posterior; between which a branch of the Ca­rotidick Artery, being drawn like a bounding River to both, distinguishes them as it were into two Provinces. Certainly, this second partition of the humane Brain also seems to be designed for its greater safety; that if perchance any evil should hap­pen to one or both the foremost Lobes, yet the latter, for that they are separated, may avoid the contagion of the neighbouring and farther spreading evil: So the Brain, like a Castle, divided into many Towers or places of Defence, is thereby made the stronger and harder to be taken.

3. Also the universal frame of the Brain appears yet more divided and variegated within all its aforesaid partitions; for all its whole exterior superficies is made uneven and broken, with turnings and windings and rollings about, almost like those of the Intestines. Those Gyrations or Turnings going from the fore-part of the Brain to­wards the latter with a creeping compass, and as it were a spiral circuit, encompasses both its Hemispheres, that they might mutually furnish all the convolutions with a continued passage: in a more moist Brain, or long kept, the Pia Mater, clothing [Page 92]every one, and collecting them together, is easily pulled away; and then the turn­ings or folds being opened and separated one from another, the substance of the brain is seen to be plowed, or laid as it were with furrows; out of which arise banks or ridges of broken crevices, not in a direct series, but cross-wise; so that in the bot­tom of every furrow, a convolution arising from the right side, is carried to the left, then others following next, being sent from the left side, is drawn to the right, and so by turns the inequalities of the whole brain are variegated in this order.

If it be inquired into, what benefit its Turnings and Convolutions afford to the brain, or for what end its whole anfractuous or broken crankling frame is, we say, that the brain is so framed, both for the more plentiful reception of the spirituous aliment, and also for the more commodious dispensation of the animal Spirits for some uses. As to the aliment to be bestowed on the brain, because it is required to be subtil and extremely wrought or elaborated; therefore it ought to be admitted, not by a more open passage, but only by very small pores and passages. Wherefore that there might be sufficient plenty of spirituous liquor supplied, it is not only drunk in every where in the plain superficies of the brain from its Cortical substance; but that superficies of the brain or Cortical substance is uneven and rough with folds and turnings about; that the spaces for the receiving the Juyce might be enlarged as much as may be: For the anfractuous or crankling brain, like a plot of ground, planted every where with nooks and corners, and danks and mole-hills, hath a far more ample extension, than if its superficies were plain and even. Further, those crank­lings of the brain do more fitly hide the sanguiferous Vessels, for that they are very small and slender, and more safely keep them, being variously interwoven into one anothers infoldings, than if they should be openly distributed; for so being carelesly laid, they would be liable to too frequent hurt.

But a reason and necessity of the turnings about in the brain, and not of lesser mo­ment than the other, is fetched from the dispensation of the animal Spirits. For as the animal Spirits, for the various acts of Imagination and Memory, ought to be moved within certain and distinct limited or bounded places, and those motions to be often iterated or repeated through the same tracts or paths: for that reason, these manifold convolutions and infoldings of the brain are required for these divers man­ners of ordinations of the animal Spirits, to wit, that in these Cells or Store-houses severally placed, might be kept the species of sensible things, and as occasion serves, may be taken from thence. Hence these folds or rollings about are far more and greater in a man than in any other living Creature, to wit, for the various and mani­fold actings of the superior Faculties; but they are garnished with an uncertain, and as it were fortuitous series, that the exercises of the animal Function might be free and changeable, and not determined to one. Those Gyrations or Turnings about in four footed beasts are fewer, and in some, as in a Cat, they are found to be in a cer­tain figure and order: wherefore this Brute thinks on, or remembers scarce any thing but what the instincts and needs of Nature suggest. In the lesserfour-footed beasts, also in Fowls and Fishes, the superficies of the brain being plain and even, wants all cranklings and turnings about: wherefore these sort of Animals comprehend or learn by imitation fewer things, and those almost only of one kind; for that in such, di­stinct Cells, and parted one from another, are wanting, in which the divers Species and Ideas of things are kept apart.

But that in more perfect Animals, all the turnings about are made of a twofold substance, viz. Cortical and Medullary; the reason seems to be, that one part may serve for the production of the animal Spirits, and the other for their exercise and dispensation. For we may well think, that the animal Spirits are wholly or for the most part procreated in the Cortical substance of the brain; for this severs and re­ceives immediately from the blood the subtil liquor, and imbuing it with a volatile Salt, exalts it into very pure Spirits. It is obvious to every one, that the Arteries enter the Cortex of the brain with a more frequent insertion of shoots, and instil to it a spirituous liquor; the leavings of which, or what is superfluous, the Veins in like manner entring it, do sup up and carry away; in the mean time, the more subtil portion being here set free, goes into Spirits. In truth, the blood waters the medullary substance of the brain in a very small quantity; which seems truly to be rather for the sake of exciting of heat, than that the animal Spirits should there be generated by the flowing in of that blood. For indeed, the volatile Salt, which like Ferment, spiritualizes the subtil liquor stilled forth from the blood, is had more [Page 93]copiously in the Cortex of the brain, rather than in its middle or marrowy part; be­cause that part, being endued with an Ashy colour, shews by its aspect the sperma­tick Particles and Humor contained in them, in which Spirit and a volatile Salt very much abounds; yea and plainly resembles an Armeniack smell, (such as either part alike breathe forth.) In the mean time, the medullary part of the brain seems very like the oblong marrow and the spinal. But it is well enough known, that these me­dullary parts serve for the exercise and dispensation of the animal Spirits, and not for their generation. The sign of which is, that where-ever an obstruction happens in them, whatever is below, being destitute of the influx of the Spirits, suffers an Eclipse; whence it follows, that the animal Spirits, irradiating the medullary Rope, are not produced in it, but flow in from elsewhere; and why should not we think the same of the middle marrow of the brain? Truly, that this part is rather the Mart or Exchange of the Spirits than its Shop or Work-house, appears from hence, because the Animals which excel in Memory, Imagination, and Appetite, are fur­nished with a more ample marrow of the brain; as is observed in man and the more perfect four-footed beasts: and they who seem to have little need of those Faculties, as the lesser four-footed beasts, also Fowls and Fishes have the Cortex of the brain greater, but the medullary part very small. It is a familiar Experiment among Boys to thrust a needle through the head of a Hen, and that she in the mean time, whose brain is so pierced through, shall live and be well a long time. The reason of which is, because the whole substance of the brain in these sort of Animals is almost merely Cortical; wherefore from the suffering such a hurt, (as long as the marrow remains unhurt) the Spirits are generated in a lesser quantity, but their commerce to the necessaries of life, are not therefore presently interrupted. Indeed the brains of Birds consist almost wholly of a Cortical and Ashy part; and the medullary part is exceeding small, and is only like a smaller Nerve descending on either side from the substance of the brain it self.

After the animal Spirits are begot by a constant afflux of the blood within the Cortex of the Brain, being there begotten, having obtained a watry Vehicle, they flow pre­sently more inwardly, and soon enter into the marrows, filling the furrows and baulks of all the turning and winding Crevices; from whence being carried farther through all the particular tracts of each marrow into the marrowy substance, which lyes under all the winding Crevices, as their common Basis, they are brought at last into the Callous Body, as into a spacious field; where, as in a free and open place, these Spi­rits being newly produced, are expatiated or issue forth.

5. Indeed this medullary substance called the Callous Body, which chambering the more inward superficies of the brain, receives into it self the marrow of all the tur­ning Crevices, seems to be made for that end, and disposed there for the same purpose; to wit, that the Spirits flowing into it on every side, might be stretched out as in their proper Sphere, and begin to exercise the acts of the animal Faculties. In this place, they which come out of the several winding Crevices, do meet toge­ther, and remain as in a publick Emporium or Mart; from whence, as occasion serves, they are raised up, and drawn forth for the uses of every Faculty. But whilst they here remain at leisure and not busied, they become purified or refined more and more by a continual circulation: because these Spirits new-born, do gently and per­petually flow on every side from the outmost bounds of this body (to wit, where this common marrow besmears the hinder productions of the brain, or the border of either of its Hemispheres) towards the fore-part of this callous Body, where it is thick­est; and there, if there be need, they are employed on the act of the Imagination, or entring the shanks of the oblong Marrow, they actuate and inspire the nervous Appendix: but what Spirits are remaining there, after these offices are served, run forthwith into the Fornix, and passing through its passage, they are remanded back again to the hinder region of the brain by a certain circulation; and lastly, after this manner, penetrating through the narrow passages of the Fornix, those Spirits are made more subtil, and also, as it seems most likely, they perform in this circulary motion those more subtil acts of the Phantasie.

6. Truly, that we may here speak something of the Fornix, it seems that this part serves for a twofold use: viz. first, lest the more inward sides of the Brain hanging slack and loosly, might fall together among themselves, or might be removed beyond the limits of a just protension or out-stretching; for they, not only by the coming between of the Pia Mater, and by little cords drawn from it, cohere to [Page 94]the oblong marrow and the Cerebel; but besides, the Fornix, like a Ligament or string brought from one end of the brain to the other, constrains and keeps its whole frame in its due figure and situation. For this part purely medullar, and of the same substance with the callous Body, seems to be a certain process of this, which arising more forward between the streaked bodies, and falling upon the two shanks of the oblong marrow, first of all distinguishes them; afterwards, being separated from them, is carried through the midst of the cavity, and about the hinder part of the brain is divided as it were into two Arms, which being bent on both sides, and again cleaving to the border of the callous Body, strictly embrace the oblong marrow, and knit and firmly tye the hinder bulk of the brain to its Trunk, lest it should flow or slide forth. But the other, and that the more noted use of the Fornix seems to be what we but now mentioned; to wit, that the animal Spirits may immediately pass through its passage from one end of the brain to the other, and so; as it were through the bill of a Pelican, they might be circulated into their own intorted belly.

That those things which were but now declared concerning the Penetralia and in­ward recesses of the Brain, may be the better understood, we will here add a Scheme of its Sphere turned inside out, and stretched out as it were upon a plain, so that the concave and inmost superficies of the callous Body, together with the Fornix, may be sufficiently seen.

CHAP. XI.

HItherto setting forth the uses and offices of the Brain, properly so called, and of its parts, we have shewed after what manner the animal Spirits are pro­created from the blood in this their principal Shop or Work-house; and in­to what diverting places, they being newly brought forth, do depart of themselves, and are there kept as it were in distinct Cloisters or Cells to be drawn forth for the manifold Exercises of the animal Function. But because these Spirits, so brought to perfection, and ready for their work within the same parts of the Brain, enter into other manner of motions, and divers ways of emanations; therefore before we proceed any further, for the searching out their tracts within the oblong Marrow and Cerebel, we ought to declare concerning these Spirits disposed within the confines of the Brain it self, with what forces they are furnished, in what form they unfold themselves, and in what ways they diffuse themselves and go forward as often as being mustered in due order, they produce the acts of the Imagination, Memory, Appetite, and other superior Faculties of the Soul. But for as much as hereafter, when we have finished the explication of the Head and nervous Appendix, we have resolved, for a conclusion, to treat of the Soul of Brutes and its powers, I may there­fore for the present lay aside this task; unless that in the mean time it may not seem amiss to give a taste only in general of these few things: viz. as there are two parts of the inferior Soul, or of Beasts, to wit, the vital or flamy, being inkindled in the blood, and the sensitive or lucid, being diffused through the whole Head and its nervous dependences, the animal Spirits being continually produced in the Brain and in the Cerebel, do constitute a double as it were Root or Fountain of this lucid part: yea, the Spirits of either linage, for as much as they are continued both within those Fountains, and from thence through the frame or substance of the nervous System, as it were under the same beamy Systasis and contexture, they effect or cause the whole Hypostasis or subsistency of the sensitive Soul.

But there happen to this Soul, because it is apt to be moved with a various impulse, and so to contract or dilate its species in the whole, or in part, for that reason divers manners both of Actions and of Passions, to wit, the Senses, which we call its Passions; and Motions, which we name the Actions of the same. The formal reason of the former, viz. the Senses, consists in the retraction or drawing back of the Spi­rits, or a flowing back towards their Fountains. For where-ever the impression of a sensible object is carried to this radiant or beamy contexture, presently either the whole frame, or some portion of it, whereby it admits the species, is compelled to wag, and to be moved back, as it were to leap back and recede into it self: on the contrary, the actions or motions of this Soul are made, for that this shadowy Spirit, being incited or stirred up in the whole, or in a certain part, unfolds it self more largely, and by an emanation, and as it were a certain vibration of the Spirits, exerts or puts forth its virtue and force of acting.

Both the Senses and Motions of this sensitive Soul are made either transient, when the Spirits, or its constitutive Particles, being moved somewhere in the System of the Nerves, draw together with them the containing parts, and deflect them with the like carriage or gesture with themselves, as is observed in the five outward Senses, and the local motions of the Members: or else, either both Actions and Passions are continuing, to wit, when both the Motions and Senses are silently performed without any great agitation or moving of the body, or its parts, within the first Fountains of the Soul, viz. the Head it self. These kind of Passions indeed, made within the substance of the Brain, are the common Sense and Imagination; but the Actions are Memory, Phantasie, and Appetite: and either of these, as to their beginnings and instincts, depend for the most part upon the outward Senses.

Concerning the former, we take notice, that as often as the exterior part of the [Page 96]Soul being struck, a sensible impression, as it were the Optick Species, or as an un­dulation or waving of waters, is carried more inward, bending towards the cham­fered bodies, a perception or inward sense of the Sensation outwardly had or received, arises. If that this impression, being carried farther, passes through the callous Body, Imagination follows the Sense: Then if the same fluctuation of Spirits is struck against the Cortex of the Brain, as its utmost banks, it impresses on it the image or character of the sensible Object, which, when it is afterwards reflected or hent back, raises up the Memory of the same thing.

The active Powers of this Soul, viz. Local Motion, Memory, Phantasie, and Appetite follow sometimes immediately the Passions, sometimes are induced apart from them upon other occasions. For indeed the sensible impression striking the streaked or chamfered bodies, oftentimes, the Brain being in no wise affected, cau­ses the local Motions to be retorted with a reciprocal tendency of the animal Epirits; so in sleep (the Appetite knowing nothing of it) when pain troubles, presently we rub the place, moving the hand to it: but more often, after that the sensible Species, having past from the common Sensory to the callous Body, hath stirred up the Imagi­nation, the Spirits, reflecting from thence, and flowing back towards the nervous Appendix, raise up the Appetite and Local Motions, the Executors or Performers of the same: And sometimes a certain sensible impression, being carried beyond the callous Body, and striking against the Cortex of the Brain it self, raises up other spe­cies lying hid there, and so induces Memory with Phantasie, also often with Appetite and Local Motion associates. Further, these active Powers, sometimes upon other occasions, are wont to be stirred up and exercised apart from Passion. In Man, the Rational Soul variously moves the sensitive, and at its pleasure draws forth and brings into act its Powers, sometimes these, sometimes those. Moreover, the blood boil­ing up above measure, and by that means striking impetuously the border of the Brain, excites the species of things lurking in it, and driving them forward towards the middle or marrowy part of the Brain, causes also the various Acts of the Phantasie and Memory to be represented.

Concerning the aforesaid interior or abiding Faculties, we shall at present further take notice, that their more perfect Exercises are chiefly and almost only performed by the Spirits already perfected and highly elaborated; for those a making, or that are new made, being numerous, they very much obstruct and hinder the acts of the animal Function: to wit, when from the Vessels, on every side watering the Cortex of the Brain, the subtil Liquor is plentifully instilled for the matter of the animal Spirits, this flowing inwardly stuffs all the pores and passages of the Brain, and so ex­cludes for that time the Spirits from their wonted tracts and orbs of expansion. Where­fore whilst the chief reflection of the Brain and Spirits is celebrated, sleep, or an Eclipse of the animal Spirits happens; then waking returns, when from the Liquor instilled, the more subtil part is exalted into very pure Spirits, and at length the more watry, being partly resolved into Vapours, is exhaled, and partly supped up by the passages of the Veins entring the substance of the Brain, or else is sweat out into the vacuity lying under the callous Body. Concerning these. I hope we may dis­course more largely afterwards. In the mean time; that we may proceed to the rest of the things proposed, concerning the frame of the Brain, properly so called, there yet remains that we speak of its Ventricles: But since they are only a vacuity resulting from the folding up of its exterior border, I see no reason we have to discourse much of their office, no more than Astronomers are wont of the empty space contained within the vacuity of the Sphere.

But in truth, as there is nothing met with in Nature that is not destinated to some use, surely we suspect this same Vacuum or empty space not to be built in vain within the Globe of the Brain. The Ancients have so magnified this Cavern, that they affirm­ed it the Shop of the animal Spirits, both where they themselves were procreated, and performed the chief works of the animal Function. But on the other side, the Mo­derns or those of later days have esteemed these places so vile, that they have affirmed the same to be mere sinks for the carrying out the excrementitious matter. But in­deed that opinion of the Ancients is easily overthrown, for that the animal Spirits, being very subtil, and apt to fly away, require not such large and open spaces, rather than the more narrow passages and little pores, such as are made in the substance of the Brain: for these Spirits (because they ought; for the various Faculties of the Soul, to be composed into various series, and divers orders and dispositions, therefore) [Page 97]ought to be moved within peculiar orbs and tracts. Further, if any one shall exactly consider the fabrick of the Brain, and seriously weigh, that these Ventricles are not formed out of the primary intention of Nature, but result only secondarily and acci­dentally from the complication of the Brain, he will be far from thinking, that the supreme seat of the Soul is fixed there, where being hem'd in with a most noble Guard of Spirits, it doth execute and perform its Functions. For it neither appears at all out of what matter, and by what artifice the Spirits are there begotten, nor by what ways of emanation they are derived from thence into the other parts of the Brain and nervous System. Wherefore almost all Anatomists, who are of a later Age, have attributed that vile office of a Jakes or sink to this more inward chamber of the Brain. To which Opinion there has been some trust given, for that these Ventricles are often seen in the dead to be filled with water; also from these, ways seem to lye open for excretion, both towards the Tunnel, and also into the Sieve-like Bone. It is observed, that where-ever the blood flows more copiously into any part, and waters it, there Vapors or watry Humors are begotten from the superfluous Serum left in the circulation, which for the most part either exhale out through vaporous Efflu­via's, or are brought back into the blood by the Veins or Lymphatick Vessels. But when the blood, by a plentiful influx, waters not only the Cortex of the Brain, but the interior marrow also, it remains, that the serous Latex (when-ever it abounds more in the blood, than that its superfluities may be reduced immediately by the Veins, or by the Lymphaeducts, if they be there, or may be separated by the Glan­dula's) should slide down into this den, made hollow within the infolding of the Brain. Truly there are many instances, which plainly evince, that the serous humors are ordinarily laid up in the Ventricles of the Brain. Anatomical Observations of men dying of many Cephalick diseases, and especially of soporiferous or sleepy di­stempers, confirm this. Yea, it may be lawfully thought, that natural sleep follows, for that the Pores and passages of the Brain are occupied and stuffed with a watry Latex, which serves for a Vehicle to the Spirits. Then as often as a profound sleep invades any one from a Surfeit, or drinking of Wine, the cause is, that the little spaces in the medullary substance of the Brain, destinated for the motions of the Spi­rits, are too much obstructed by a Narcotick or a watry humor: certain reliques of which, being resolved into vapor, and thrust out from the company of the Spirits, do often sweat out, or drop into this Vacuum or empty space.

After this manner, it may be believed concerning the Ventricles of the Brain, or the empty space left within its plicature or folding together. But in truth, because this matter hath been very much controverted among Physicians of every Age, and the right decision of it seems to be of great moment, for the explicating the offices of the other parts of the Head; I will here compare together the reasons for and against this Opinion, that we may at length give our Judgment of this Opinion, what may be either true, or most likely.

CHAP. XII.

SInce Experience testifies, that the Serum and excrementitious, I may justly say morbifick, and oftentimes deadly Humors, are found frequently within these Ventricles of the Brain; we ought to inquire more diligently concerning their passage in and out: and the rather, for that it is very much doubted by some con­cerning the use of these Dens, nor are there wanting those in this late Age, who have endeavoured to bring into vogue the ancient Opinion, though long since exploded, concerning the Spirits being begot in this place, and here exercised. I believe with­out doubting, for the reasons before alledged, that the Spirits are not here begotten, nor exercised: and no less certain is it made by Experience, that the serous Colluvies is here often gathered together. This therefore only remains, that we should see [Page 98]from whence, and how this flows hither, and then by what ways of Excretion the same should be carried out.

As to the first, it is exceeding probable, that the serous Latex, which is the Ve­hicle of the Spirits newly produced, and is introduced together with them into the Pores of the Brain, after it is grown stale, and being attenuated into Vapour, doth distil forth into this Cavern, and there at last grows into a watry Humor: for other­wise what becomes of that Humor, or into what other Receptacle could it be derived? Besides this ordinary, and I believe assiduous heaping together of the serous Colluvies within the Ventricles of the Brain, certainly it may be believed, that this kind of serous Humor is distilled out of the Glandula's inserted in the Choroeidal infolding, being too much filled, into the Ventricles so called. I have often seen in a Dropsie the Glandula's of the Brain to be intumified, and like grains of Barley, bursting with too much wet, to become flaccid or withered, so that they could not retain the sero­sities brought to them, but continually disposed them into the Cavity beneath. Truly in a Dropsie of the Brain these Cavities or Ventricles are always seen to be full of water; the cause of which kind of distemper is, the blood being made more watry, puts off in its circulation a greater heap of Serum than the Veins can presently carry back, or the Glandula's are able to receive and retain. For indeed, that the Serum, re­dounding on every side from the Vessels, may the better slide into the Ventricles of the Brain, it is so ordered, that the greater infoldings of the Vessels, with the in­serted Glandula's, should be disposed near all the Ventricles of the Head: because, not only the infolding Choroeides is placed nigh the concourse of the three Ventricles in the Brain, but another infolding, and no less noted, (which we above described) with greater Glandula's, is set behind the Cerebel nigh the fourth Ventricle. In all, as it seems, for that end such care is taken, that the watry part, coming from the blood, which is destinated either for the Brain or the Cerebel, for that it is not fit for the procreating of Spirits, might run into these infoldings of the Vessels. But yet if a greater plenty of Serum be there laid up, than can be contained in them, or may be sent away outwardly, whatever is superfluous will slide into the Cavity under­neath.

Hence it appears, from whence, and by what means the serous heap is gathered together within the Ventricles of the Brain: certainly to deny this going out is no other than to assert every ones Brain big with a Viper, which cannot be brought forth but by gnawing asunder the bowels of its parent. Who shall lightly consider the parts nigh the Ventricles, and their Fabricks, at first sight only would swear with the Ancients, that the excrements of the brain were laid aside both lower through the Tunnel into the Palate, and above or more forward through the mammillary Processes into the Nostrils: But if the structure of these parts be a little more dili­gently searched into, there is no body who presently will not easily think, that by neither of these ways the excretion of any humor can be made; for neither from the pituitary Glandula through the Wedge-like bone, nor from the mammillary Pro­cesses through the holes of the Sieve-like bone, is there any manifest aperture or opening to be perceived. But in very truth, we do suppose that the brain is in some measure purged by both these Emunctories, for that objection may be answered, That the translations of Humors in living Creatures are easily performed through places that seem impervious or unpassable; for while the Pores and passages in all the parts of a living Creature are dilated by spirit and heat, they transmit the rain of the Serum as through the fine texture of a woolen Cloth. This plainly appears from Arthritick distempers, in which the serous Latex creeps by degrees through the nervous bodies, and passing through very small spaces, makes a falling down of humors sometimes upon these parts, and sometimes upon others; so that it is obvious, that the Mem­branes and nervous Processes drink in the serous humors like Sponges, and then by a light compression render them by heaps, as is manifest in the Tooth-ach; for as often as a Bodkin or Instrument is put up into a hollow Tooth, clear water will come out plentifully. Indeed, in the body of a living Creature the passages of humors are not only made through open passages and chanels; but the thinner and more watry Latex creeps through the solid and smooth bodies of the Nerves, as also the Fibres and the Membranes, as through the holes of a Filtre, and so is transferred through impercepti­ble straits from place to place. I sometime knew in the Impostume of the Lungs the humor to have been derived through the Membranes growing to the Pleura from the bag into an Issue made in the side, and so the spitting ceasing, the disease that seemed [Page 99]otherwise incurable, was healed by such a way of Evacuation. Why in like manner may we not suppose the serous humors falling down from the Ventricles of the Brain into the pituitary Glandula, and the mammillary Processes to be carried away through the Nerves or Membranes passing through here or there?

Concerning the Tunnel, the thing is probable enough; because the position and structure of this seem to shew, that some humor is carried out of the Ventricles of the Brain towards the pituitary Glandula. For this part is so constituted, that a falling down of the humors may be made from every angle and recess of the interior Brain and its Appendix into its aperture or opening. And as in several Animals, the figure and site of the Ventricles vary very much, (as we have already shewn) yet in every one of them all the Ventricles of the Head, whatsoever they be, have their openings gaping towards the Tunnel. But that this Kernel or Glandula, to which the passage of the Tunnel is inserted, receives and carries out the serous humors, seems also to appear from hence; because it admits, not only those falling from the brain into its Pores, but also those secreted from the blood ascending into the brain: For that in many four-footed beasts, certain Vessels are inserted to this Glandula from either Carotidick Artery, which intimately enters its substance: a sign of which is, that Ink being injected into the Trunk of either Artery, dyes with a black colour the wonderful Net, if it be there, and oftner the interior substance of this Glandula: whence it may be argued, that the office of this Glandula is to receive the superfluous serosities; and it receives not only those sent away in the return from the brain, but sometimes preoccupies or prevents them, and is wont to derive them from the blood before it is carried to the brain. And therefore this Glandula is very small, if the superfluities of the Serum be derived to it only from the brain; but greater, if they come to it also from the blood, to wit, as it executes either one or a double office, as we have already shewn at large.

But as to what respects the way of passing through, to wit, by which the humors, deposited in this Glandula, are carried out, the vulgar Opinion is, that they do come away through the holes of the bone beneath into the Palate: wherefore in those kind of Animals, who have the wonderful Net, and many of its shoots enter this Glan­dula, more holes are made in the underlying bone. Further, if you take away the ditch or gutter of the Wedge-like bone, or the seat of this Glandula, cut off from the Skull, and pour water upon its holes being made bare from the Membrane, it passing presently through the substance of the whole bone, will suddenly still forth through other holes lying open in the sides of the bone. Yet this Experi­ment concludes nothing for the Opinion proposed: because these holes are wholly wanting in some Creatures, and very much in an humane Skull; in those who have them, as in a Calf, especially it is observed, that the same are filled by some hol­low Vessels; into which if a black liquor be cast by a Syringe, that passing through the substance of the bone, will go into many other Vessels lying under the bone, and at length into the Trunk of the Jugular Vein; which certainly is a sign that the hu­mors are not carried from hence into the Palate. But as to the Vessels which cover over the holes of the bone, and which more abundantly lye under the same, they seem to be either Veins or Lymphaeducts.

But among these it is lawful to conjecture, the chief means of Excretion, whereby the serous humors, laid up in the pituitary Kernel, may be carried out; to wit, that they are remanded back from it, as from most other Glandula's or Kernels, into the mass of blood. In a Calf the thing lies open to ocular inspection, nor is it to be doubted of other Animals, who have the admirable Net: because, as the arterious branches, so also the veinous reach to this Glandula; which sup up not only the humors deposited from the Arteries, but also those falling from the Ventricles of the Brain. Yea, it may be lawfully believed, that in a Man also, a Horse, and in other Creatures, who want the strange or wonderful Net, there are other Lymphaeducts or Water-carriers, or some such kind of Vessels, as are seen in the head of a Calf, that most certainly carry the humors from this Glandula. We cannot so easily find out their footsteps, because, before these break out of their dens, the tracts of the Lymphaeducts, if there be any, would vanish. Nor can we find out these Vessels in all, as in a Calf, by injection; because the holes of the bone, by which, as by the leading of a thread, the injection arrives at, and dyes the Vessels, otherwise lying hid, are [...]nting in most. No doubt but time will render sufficiently manifest the reductions of the humors from the pituitary Glandula in other living Creatures: in [Page 100]the mean time, it may be lawfully suspected, for that the serosities in some are re­manded from thence into the bloody mass, that in all it is done after the like or the same manner, although the ways of the passing do not yet sufficiently lye open.

As to the other Emunctory of the Brain, to wit, whereby the serous humors, laid aside from the Ventricles of the Brain into the mammillary Processes, and thence are thought to be sent away through the holes of the Sieve like bone: truly, concerning this way of Excretion, it is much more to be doubted, because these holes in the defunct being covered over and fully stufft, with the insertions of the Dura Mater and nervous Fibres, sent on either side from the mammillary Process, transmit no­thing of humor, how clear soever it be. Further, there is nothing more certain, than that the serous humors are pressed out from the Glandula's and extremities of the Vessels ending within the Nostrils into their Caverns; so besides that 'tis scarce possible for the humors to descend thither from the brain, it is not absolutely needful to suppose this sort of means of Excretion. But that we may reason a little farther concerning these; if it may be lawful to argue from the provision, and from the effects of the parts, there is no reason but that I may probably believe, that some humors also do shower down from the Brain into the cavities of the Nostrils: for it being supposed, that the serous humor passes through, not only open chanels, but the more strict Pores and passages also of the Nerves, and creeping both through the Fibres and Membranes, as through the straining or holes of a Filter or Strainer, is carried from place to place, (which it were easie to demonstrate) what should hin­der but that the same sort of Latex may descend through the Fibres impacted in the holes of the straining bone? For although in dead Creatures those parts seem to be impervious or unpassable, yet during the life of the Animal the passages and blind ways of the nervous bodies, being dilated by Spirit and Heat, most easily transmit a copious humor wherewith they are watered.

The Sieve-like Bone in divers Animals is variously perforated for the manifold necessity and difference of smelling. A Process from the Dura Mater and mani­fold nervous Fibres pass through every one of its holes, and besmear the inside of the Nostrils. But as the impressions of sensible things, or sensible Species, continued as it were by the undulation or waving of the animal Spirits, ascend through the passages of these bodies stretched out from the Organ towards the Sensory; so the humidities wa­tring the same bodies, for as much as sometimes they may be more superfluous than usual, may distil into the Nostrils through the same ways. For indeed such humors as are perpetually to be sent away from the brain, ought so copiously to be poured upon the Organs of Smelling, as we shall shew hereafter, when we shall speak particularly of the smelling Nerves; in the mean time, that there is such a way of Excretion opening into the Nostrils, some observations, taken of sick people troubled with Cephalick dif­eases, do further perswade. I have known some very obnoxious to the Scotomy and Vertiginous distempers, who had great plenty of clear water that distilled forth about the end of the Fit; by which kind of Evacuation, as it were Critical, the Fit was wont to be ended. Not long since, a Virgin living in this City, was afflicted a long time with a most cruel Head-ach, and in the midst of her pain much and thin yellow Se­rum daily flowed out from her Nostrils: the last Winter this Excretion stopped for some time, and then the sick party growing worse in her Head, sell into cruel Con­vulsions, with a stupidity; and within three days dyed Apoplectical. Her Head being opened, that kind of yellow Latex overflowed the deeper turnings and wind­ings of the Brain and its interior Cavity or Ventricles. I knew a Gentlewoman that was wont to be infested with a most cruel Head-ach, also with a Vertigo, and a frequent melting of the animal Spirits, or Swooning away; who when she began to be better, after a grievous Fit, felt at first a creeping motion in the top of her Brain, as it were the sliding down of water: then that motion passing a little more forwards and downwards, at length many drops of clear water distilled from her Nostrils. This Symptom she used to have so ordinarily, that the sick Gentlewoman did not doubt but that this water stilled out from the brain it self. I could here bring many other reasons, which might seem to perswade, that the Ventricles of the Brain, or the Cavity made by the complicature or folding up of its border, is a mere sink of the excrementitious Humor; and that the humors there congested, are purged out by the Nose and Palate: But it is time for us to hasten to other matters, and to pass from the Brain, properly so called, to its Appendix, viz. the oblong Marrow and the Cerebel.

CHAP. XIII.

WE will pass now from the Brain to the explication of its Trunk, to which both it and the Cerebel do grow like Mushrooms or large Excrescences. This part is commonly called the Oblong Marrow; under which name we comprehend all that substance which reaches from the inmost Cavity of the callous Body, and conjuncture in the Basis of the Head, to the hole of the hinder part of the Head; where the same substance, being yet farther continued, ends in the spinal Marrow.

The superficies of the oblong Marrow, though it be made unequal with some pro­tuberances and processes, yet it is not variegated or garnished with any turnings about, and involutions, as it is in the Brain and Cerebel; neither is its exterior and cortical substance, or of an Ash-colour, and the interior, medullar or marrowy and white; but all its frame or substance is in a sort marrowy or medullous: nor does it however appear pure and bright, but much darkened with fibres and hairs vari­ously stretched forth, and diversly going out. To wit, its fibres being figured in various places, after a diverse manner, in some places they are found chamsered, and as it were beamy, in others direct or stretched out at length, and in other places again circular.

The figure of this is forked, and as it were like the Poets Parnassus, seems like the ter Y: for its shanks arising more forward from [...]her Hemisphere of the Brain, and inclining one to another, grow together near the centre of the Skull into one and the same Trunk; which notwithstanding, a line being brought through the midst, seems to be made as it were out of two stalks, and those to be distinguished in its whole process.

The oblong Marrow seems to be a broad or high Road, into which the animal Spirits perpetually flow from their double Fountain, to wit, the Brain and the Cere­bel, to be derived from thence into all the nervous parts of the whole Body: which Spirits, whilst they are orderly disposed in this common passage, as it were by series and orders, carry a twofold aspect; to wit, they are directed either outward to­wards the Nerves, when they exert the loco-motive Faculty, or they look inward towards their Fountains, when the acts of sense, or rather the apprehensions of sen­sible things are performed.

Within this open way, a more large and greatly open path leads straight to the spinal Marrow, through which the Spirits flow forth to the Nerves, the Executors of spontaneous Motion in most members. In the mean time, out of the same tract of the oblong Marrow, lesser paths are carried outwardly, here and there, by parti­cular Nerves, arising from the same, within the Skull. Also besides, many diverting places, viz. various processes and protuberances grow to this medullary Trunk, into which, the Spirits destinated to some peculiar offices, go apart: lest that all the Spi­rits travelling this way and that way in the same path, should meet one another and disturb one anothers offices.

Whilst after this manner, for the performing the acts of Motion and Sense, we suppose the animal Spirits to be expatiated within the oblong Marrow; we affirm, that they are not there begotten, but only exercised. For indeed, they being created only in the Brain and Cerebel, as they proceed from this or that, they perform the offices, [...]either of a merely involuntary Function, or else of a spontaneous, as shall be shewed mo [...] [...]argely hereafter.

But that we may unfold here all things which belong to the oblong Marrow, I shall mete it forth from its first coming out to the end of its race, and handle its several St [...]dia; diverting places, and cross ways. Where the callous Body is thought to end, the oblong Marrow begins; to wit, when the medullar substance of the Brain is thickest nigh the bosses or knobs of either Hemisphere, a body of a whitish colour and somewhat darkned or obscured, and streaked like Ivory, is joyned to that marrow on both fides. These two bodies are the extremities or tops of the shanks of the ob­long [Page 102]Marrow; between which and the Brain there are nigh and very immediate commerces. Either of these seems as it were a Cylinder rolled about into an Orb, which nevertheless constitutes the top of either shank, not spherical, but oval, and something bent downward in the hinder part. A more large portion of its superficies is joyned to the medullar substance of the Brain; but yet some part of it, being free from the cohesion with the Brain, shews it self apart, and makes that protuberance shewing it self in either lateral Ventricle. These bodies, if they should be dissected along through the middle, appear marked, with medullar streaks, as it were rays or beams: which sort of chamferings or streaks have a double aspect or tendency; to wit, some descend from the top of this body, as if they were tracts from the Brain into the oblong Marrow; and others ascend from the lower part, and meet the aforesaid, as if they were paths of the Spirits from the oblong Marrow into the Brain. And it is worth observation, that in the whole Head besides there is no part found chan [...]ered or streaked after the like manner.

If the use of these be inquired into, this presently occurs, that these bodies, placed between the Brain and its Appendix, are the great and common diverting places of either; to wit, which receive whatsoever impulses or forces of the animal Spirits are sent from either, and communicate them presently to the other: Or that I may speak more plainly, this part is the common Sensory, to wit, as Aristotle saith, [...], the first Sensory that receives the strokes of all sensible things, dilated from the Nerves of every Organ, and so causes the perception of every sense; which kind of strokes of sensible things, when from hence they are passed further into the Brain, presently Imagination succeeds the Sense: and further, these bodies, as they receive the forces of all the Senses, so also the first instincts of spontaneous local motions. To wit, as often as the Appetite discerns any thing to be done, presently the reci­procal tendencies of the animal Spirits, that is, from the Brain into these parts, are disposed here to act the conceptions of motions coming from any part or member. For here, as in a most famous Mart, the animal Spirits, preparing for the performance of the thing willed, are directed into appropriate Nerves. That it is so, it appears, because every influence from the Brain into the nervous stock, and on the contrary, from this into that, and the mutual commerce of the animal Spirits, must of ne­cessity pass through these bodies. Wherefore all the Nerves, also those which belong to the more inward Organs of the Senses, arise behind these chamfered bodies. For the Optick and smelling Nerves creep through the superficies of the Brain by a long passage and windings about, that they might be inserted below this part of the oblong Marrow.

For indeed, the Species of sensible things, received by those Nerves, might more immediately be carried to the middle of the Brain, unless that they ought first to be staid at this Sensory. Further, we may lawfully conjecture, that these parts per­form the aforesaid office from their chamfered, and as it were beamy contexture: For as those chamserings, with which these bodies are marked, (as we but now inti­mated) are of a double kind, to wit, some descending, which look from the Brain towards the oblong Marrow; and others ascending, which are carried distinctly from this towards that, it may be lawfully concluded, that in these carried up­wards, the impressions of sensible things are perceived: and in those tending down­wards are performed the Instincts of Motions.

Further, that these bodies, as was said, perform the offices of the first Sensory, besides the fabrick of their parts, and the Analogy to be collected thence of their use, it seems yet more certainly to appear from some Observations concerning these chamfered bodies, after what manner they are affected in Paralytick diseases. For as often as I have opened the bodies of those who dyed of a long Palsie, and most grievous resolution of the Nerves; I always found these bodies less firm than others in the Brain, discoloured like filth or dirt, and many chamferings obliterated. Fur­ther, in Whelps newly littered, that want their sight, and hardly pen [...] the other faculties of motion and sense, these streaks or chamserings, being scarce wholly for­med, appear only rude.

The chamfered Bodies, inclining one to another near their blunt and greater angles, are almost contiguous; but that the Trunk of the Fornix intervenes with its twofold Root: yet in that place where the two Roots of the Fornix, being sent straight down, are inserted into the callous Body, a transverse medullar process, like a great Nerve, stretched from one chamfered body to the other, as it were joyns the same, and [Page 103]makes them to communicate one with the other. Certainly, this joyning together of the chamfered bodies is made, that their actions and passions may not be double: but though the species of the sensible object or conceptions of the motions to be per­formed, coming from the Brain or Sensory being double, are carried also double to the first Sensory; yet for as much as either substance or frame of this, communicates with the other, every impression coming this or that way, becomes still one and the same. For it may be observed, in the whole Head, that though almost all things are double, yet each of them communicate among themselves, either by a contiguity, or by processes sent forth. And so as by the duplication of it, care is taken against the absolute privation or defect of the act, so the joyning together of its duplicature provides against the empty or confuse multiplication of the same species.

After this manner, the chamfered bodies in Man and four-footed Beasts are con­stantly found of the same species or form, and in every one of them, figured after the same manner; and are as it were the Joynts that joyn the Brain to the shanks of the oblong Marrow. But we have already shewn, that in Fowls and Fishes, whose brains being alike, differ from those of men and four-footed beasts, the thing is somewhat otherwise: For in Fowls the callous body is wanting to the brain; but what serves instead of it, is found in the oblong Marrow, to wit, two little Ventri­cles shew themselves nigh the chambers of the Optick Nerves, which are arched or chamber'd with a whitish substance, such as the callous body is in man or four-footed beasts. Then on the contrary, the chamfered bodies, or the parts which serve in their stead, in Fowls, are not a portion of the oblong Marrow after the usual manner, but are entred into the Brain it self. For near the fissure of the Brain, two Mem­branes being marked with medullar chamferings, both distinguish either Hemisphere of the Brain, and cover over its Ventricles. The streaks or rays of either Membrane descend, and being concentred about the Basis of the Brain, go together into a me­dullary process, which is inserted on both sides to the oblong Marrow. So these parts, viz. the callous body, in which the animal Spirits are expanded, and the chamfered bodies, in which their passing to and fro is instituted, seem to be trans­posed in the head of Fowls. The reason whereof, (as I elsewhere hinted) unless I be deceived, is this: because these Animals are of less excellency in Imagination and Memory than four-footed beasts; yea also, for that the sense and motion of them are their chief Faculties: therefore for the exercises of these to be performed with a greater expansion of Spirits, the callous body is transferred into the oblong Marrow, and in its place the chamfered bodies are removed into the Brain.

About the lower end of either chamfered body the smelling Nerves are inserted. For you may take notice, that the mammillary Processes, a little more obscure in man, but much more conspicuous in brute Animals, who are endued with a more remarkable sense of smelling, do pass into firm and plainly whitish bodies of Nerves, which being dilated or brought nigh the lateral turnings and windings of the Brain, are implanted into the oblong Marrow on either side about the lower angle of either Ventricle behind the chamfered bodies; yet so, that the Tube or Pipe of either Nerve may open into the Cavity of the Ventricle, as we before shewed. After this manner these Nerves are carried by a long journey from the fore part of the Brain, that they may bring the sensible species to the chamfered body, as to the common Sensory, first and rather than to the Brain. But we shall speak of the smelling Nerves more particularly hereafter.

Where these chamfered Bodies end from either side, a marrowy substance succeeds, which being somewhat of a darkish colour going forward for some space, is distin­guished by a peculiar bending forward from the other contiguous parts. This Galen (perhaps not improperly) calls the Chambers of the Optick Nerves; for in this place the Optick Nerves shewing themselves from the highest region of either side, being carried downward with a certain compass, are united about the Tunnel. Then being divided again, and carried a little further, enter the Skull, going straight forwards to either Sensory. The growing together of these Nerves, and their being again separated, seems to be ordained for this end, that the visible species, received from either Eye, might appear still the same, and not double; for this conjunction of the twofold Organ frames the double image into one; which once united, when after­wards it is carried to either side of the common Sensory, for that it is on both sides alike, appears still the same. If at any time, through drunkenness, or a distortion of the Eyes, the object appears double, and two Lights upon a Table, it is because [Page 104]the image of the same thing is received after a different manner by one Eye than the other, for that reason the objects are represented like two distinct things. For that this Eye is distorted after one manner, and that after another, the same Species, coming to either Pupil by a diverse angle of incidence, appears diverse or double. There is another reason of the coalition of the Optick Nerves, to wit, that one Eye being hurt, all the visible animal Spirits might be bestowed on the other. Further, for that these Nerves are carried with a long passage, their uniting helps to their mu­tual strength and support.

Whereas the Optick Nerves arise here from the oblong Marrow, all or its most in­timate substance is not bestowed upon them; but these Nerves are inserted into the me­dullar Trunk, as branches of a Tree to the stock, that so they may receive by that means the influence of the Spirits, and by this way transmit the Species of visible Things. In the mean time, this more inward substance of the oblong Marrow is the common passage both to the Eyes and to the other nervous System arising more backward: through which, by the going and returning to and fro of the animal Spirits, the im­pulses of sensible things, and the instincts of Motions between the Brain and the other nervous parts, which depend upon it, are performed. Forasmuch as the smelling and seeing Nerves arise so near the chamfered bodies, the reason hence is plain, why odors or the objects of the sense of smelling so strike the Brain it self, and im­mediately affect it; also why there is so exceeding swift a communication between Sight and Imagination.

Concerning the Optick Nerves in a man, (which also in some measure is after the same manner in other living Creatures) we shall advertise you, that when they, after their uniting or mixing together, being presently again separated, do go out of the Skull, the sanguiferous Vessels going out of the Skull with them, and follow­ing either Nerve even to the Basis of the Eye, are knit into the Trunk of either. There is a noted shoot of the Artery destinated to this office, carried from the an­terior branches of the Carotides. Hence, as I suppose, a reason may be given, where­fore, when by drinking or more plentiful eating, a sleepiness is caused, presently a great heaviness, and as it were an oppression, is felt about the Eyes. For when the blood, very much boiling up, fills above measure the Vessels watering the Brain, and by distending them, obstructs the Pores of the Brain, those Nerves also from the blood in like manner boiling up within the Optick Vessels, are pressed together in their whole passage.

In Fowls and Fishes this chamber of the Optick Nerves, bunching out with a great bulk, is not much less than the Brain it self; for, as we but now intimated, what is instead of the callous body is placed here; and in this place the animal Spirits seem to have their chief Mart or Empory in a most large medullar chamber, or the Sphere of their Expansion. And so, when from hence the animal Spirits are derived from so full and plentiful a Store-house, it is for that reason Fowls are furnished with so curious an Eye, and with so highly perspicacious and acute a sight. And the same perhaps may hold concerning Fishes, if that we consider the sight in these is perform­ed in a thicker Medium, and often double.

In some Animals, in the midst of these chambers of either Optick Nerve, the shanks of the oblong Marrow a little opening, leave a chink or aperture, which receiving the serosities coming from every region of the Brain and its Appendix, sends them through the Tunnel into the pituitary Glandula.

There is no need that we should discourse much here of the Tunnel and the pitui­tary Glandula, because, already speaking of the Ventricles of the Brain, or the em­pty space left within its plicature, we fell occasionally on the consideration of both these; where we shewed, that the serous humors, which were wont to be heaped together within many places of the Brain and of its Appendix, do all slide down on every side from each angle and recess of it into the steep opening of the Tunnel; and so there is a necessity that they should be poured out by it into the pituitary Glandula. Further, it is manifest, that this Glandula, in some Animals, is charged with a double office; to wit, as it receives the serosities sent from above from the Brain, so also it separates the humors from the blood brought to the same from the wonderful Net by the Arteries, and prepossessing them, imbibes them before their ingress to the Brain. Wherefore this part is furnished with a substance of a double kind: viz. one reddish, more thin, and interwoven with Blood-carrying Vessels, which consti­tutes either side of it; and the other more white placed in the middle, to which the Tunnel is inserted.

But having shewn, that this Glandula receives the humors so brought by a double Tribute, we did diligently inquire concerning the ways and means whereby they are at length carried away from thence: and as it appears by an Experiment, that there is a passage open from this Glandula into the Vessels lying underneath the bone, and from thence into the Jugular Veins, we affirmed, that 'twas most likely, that the humors to be carried away from this Glandula, (after the manner of others) may be reduced at last into the bloody mass. I shall not add any more concerning these things, but proceed to the other parts of the oblong Marrow. But that, what hath been said, concerning the shanks of the oblong Marrow, and their tops, viz. the chamfered bodies, may be the better understood, it will seem to the purpose that we represent the Images of all these in the following Figure.

CHAP. XIV.

BElow the Chambers of the Optick Nerves in a common Valley which lyes be­tween the tops of these and the Buttock-form Prominences, is placed the Pi­neal Glandula or Kernel in form of a Pine apple, called also Conarium; this is not only found in Man and four-footed beasts, but Fowls and Fishes also are endued with the same. Wherefore, although from hence it may be concluded, that this is of necessary use; yet we can scarce believe this to be the seat of the Soul, or its chief Fa­culties to arise from it; because Animals, which seem to be almost quite destitute of Imagination, Memory, and other superior Powers of the Soul, have this Glandula or Kernel large and fair enough.

It is observed in all Animals of every kind and form, that to this Glandula, al­ways placed nigh the holes or passages, open to the Tunnel, the Choroeidal Infolding is continually joyned; yea this infolding (seeming to hang from the Pineal Kernel sustaining its middle Process, as it were by a nail or hasp, from thence) is divided into two wings stretching out on either side upon the shanks of the oblong Marrow, Wherefore we may justly suspect, that this Glandula is chiefly made for the sake of this infolding; and that the office of it is no other than of other Kernels, which are placed nigh the concourse of the sanguiferous Vessels: to wit, that it may receive and retain within it the serous humors deposited from the arterious blood, till the Veins being emptied, may sup them back, or the Lymphaeducts (if there be any there) may convey them outwardly. For it is observed, that the Choroeidal in­folding is beset with very many lesser Glandula's or Kernels, and every where inter­woven with them, which imbibe the Serum secreted from the blood, in the smaller Vessels; therefore for this very same office, where all the Vessels concur, this Kernel is placed, of a bigger bulk, that it might be able to receive and contain the serosities there plentifully deposited. Moreover, it is of no small moment, that this Glan­dula sustains and keeps duly stretched out the Chroeidal infolding otherwise hanging loose, and apt to fall down into it self, or at least to slide out of its proper place. Wherefore I have often taken notice in the Dropsie of the Brain, that this Glandula being loosned at the roots by too much moisture, and often broken off, and removed from its place, the Choroeidal infolding hath slid together from its proper expansion, and slip'd down lower, and also suffered its Vessels to be folded together disorderly.

From these things thus premised concerning the pineal Glandula, it will not be difficult to assign also the use of the Choroeidal infolding: Concerning which there will be little need to resel that Opinion of the common sort, which asserts, That the animal Spirits, to be bestowed upon the whole Brain, are begot in this infolding: because the Vessels of this instil nothing to the substance of the Brain or its Appendix, for that they are no where inserted to it; but it was before shewn, that the Ventri­cles of the Brain, or the Cavity in which these same Vessels are hung, do not at all contain the Spirits; which further appears more plain, because in Cephalick diseases those Ventricles are filled with water, and the continuity of the infolding is dissolved by too much moisture, when in the mean time the sick are indifferently strong in the exercise of the animal Faculties.

But indeed we suppose, that this infolding serves for a twofold office: viz. First, that the more watry part of the blood, destinated for the Brain, might be sent away into its Vessels, to the end, that the remaining portion of the bloody Latex might become more pure and free from dregs to be distilled forth into Spirits; even as is wont to be done in a Chymical Distillation, to wit, when there is a peculiar Receiver fitted for the receiving of the Phlegm by it self, more sincere, pure, and subtil Spirits are instilled into the other more noted Receiver. The more watry blood entring the arterious Vessels of this Infolding, being carried from them into the Veins, is remand­ed back towards the Heart. In the mean time, lest the Serum, too much redound­ing, [Page 107]and boiling up in these Vessels, might hinder circulation, its superfluities are received for some time both by the lesser Glandula's thickly inserted, and also by the pineal Kernel.

The other and no less noted use of this Infolding, is to conserve the heat of the blood boiling within the complications of the Vessels, and as it were circulating about, being excited as from a fire-place within the infolding of the Brain. For though the Pia Mater need not implant thick shoots of Vessels in the callous Body and inward Marrows of the Brain, for that they are rather dedicated to the Exercise than to the Generation of the animal Spirits; yet that the heat requisite for the circulation of the Spirits, might be kept constantly in that place, this infolding is hung upon the whole neighbourhood. For as the blood, aggested or heaped together within the Cavities of the Bosoms, is instead of an hot Bath, whereby the animal Spirits are distilled plentifully into the outmost and cortical part of the brain; so the blood con­tained within the small Vessels of this infolding, seems to be in the place of a lesser and more temperate Bath, whereby the same Spirits might be fitly circulated in the more inward and medullar substance.

Lastly, Another reason may also be given, why the Choroeidal infolding is found always within the Ventricles or Cavity of the Brain, made by its infolding, and after what manner soever figured; to wit, that another sort of commodity might result from thence; that when the Vessels of that Infolding, carrying too watry blood, lay aside more Serum than the Glandula's are able to receive or contain, what is superfluous might slide down opportunely into the underlying Cavity, as into a Sink. Wherefore the Pineal Glandula, though set in a more eminent place, is however placed always near the hole or passage that lyes open towards the Tunnel in every brain.

Next to the Pineal Kernel are found in the upper superficies of the oblong Marrow certain noted Prominences, which are commonly called Nates and Testes. These being placed near together, do constitute as it were four Mole-hills, which yet are joyned one to another by certain processes. Beneath these Mole-hills, or rather be­tween the joyning of them and the trunk of the oblong Marrow, placed underneath, a narrow and long Cavity or Den is left, which by some Anatomists is called the fourth Ventricle; but according to others later, who place the fourth Ventricle under the Cerebel, this Cavity is affirmed to be a passage to it.

The hinder extremity of this Den ends nigh the beginning of the fourth Ventricle; the more fore-extremity of it opens before the former Mole-hills or little bulkings out, called Nates. From the midst of this Cavity or narrow Den a passage goes straight to the Tunnel. It is very much controverted among Anatomists concerning the site of these parts, and of their dependency on one another, and of other parts, and of their use: Concerning which this is first to be noted, as we hinted above, that these four Protuberances are far greater in some brute Animals than in a Man, as in a Sheep, Calf, Goat, and the like; also in a sound, dry, and old Head they are more conspicuous, and their processes, joynings, and habitudes may be more easily noted than in a younger, moist, or otherwise sickly brain. Indeed the use of these (unless my conjecture deceives me) seems far more noble, than that they should deserve those vile names of Nates and Testes, Buttocks and Testicles.

Notwithstanding, to what office these parts were designed, neither have the ancient Anatomists delivered, nor will it, by the help of Reason, be easie to guess for cer­tain. We have already shewn, that these aforesaid Prominences ought not to be taken for the two shanks either of the Brain or Cerebel bending back one towards another, and so growing together into the oblong Marrow. For although from this supposition a very neat Hypothesis may be made for the oeconomy of the animal Fun­ction, to wit, by affirming that these double shanks, on either side, were so many distinct ways of passage through which the animal Spirits, for the performing of mo­tions, flowed from the Brain and Cerebel into the oblong Marrow, and returned thence from this into those for the performing the acts of the Senses: yet from our Method of Dissecting it plainly appears, that the brain is not fixed to the oblong Mar­row nigh this place, but far above it; so that indeed the anterior Prominences, unless mediately only, viz. by the chamfered bodies, receive not any portion of the me­dullar stock, or any influence from the brain, nor can have any dependency from it. Besides, if the Protuberances called Nates were shanks of the brain, why should the same be in man, (he having got the greatest brain, the least) or at least lesser than [Page 108]in most other living Creatures? Then between the Prominences called Testes and the Cerebel, although there happens a certain communication; yet it seems that there lyes open a passage from those little lumps into the Cerebel, and not from this, through them into the oblong Marrow. For out of these aforesaid Prominences a medullar Process ascends obliquely on either side into the Cerebel, by whose passage the animal Spirits, tending from one stage to the other, cause a mutual commerce between those parts and the Cerebel: But indeed the Processes which lead from the Cerebel into the oblong Marrow, and carry to it its influences, being distinct from the former, stand somewhat lower, as shall be more clearly shewn hereafter, when we shall speak of the Cerebel.

But in the mean time, concerning the offices and uses to which the aforesaid Pro­tuberances serve, we shall make this conjecture. The animal Spirits perpetually flow out and leap back again from the fountain the brain into the oblong marrow, so that there may be had a constant commerce between the brain and many organs of sense and spontaneous motion: from which those parts are entertained which per­form their actions, not at the beck of the Appetite, but either by the instinct of Nature, or the blind impulse of the Passions; for such receive wholly their influences from the Cerebel, as afterwards shall be more fully shewed. Whilst therefore the Spirits, flowing from the brain, abound in the oblong marrow, it is fit that some of them should be carried from thence into the Cerebel: (for what uses this ought to be done, shall be told by and by) wherefore from either side of the oblong marrow a Protuberance grows forth, into which indeed the Spirits designed for the Cerebel, may go apart from the common passage of the oblong marrow; and these Promi­nences are the former, which are commonly called Nates, and, as we have said, are far greater in most brute Animals than in man (the reason of which shall be declared anon.) The other hinder Protuberances, commonly called Testes, grow to these former, and are only certain Epiphyses or Excrescences of them, as it were the heads of the medullary Processes, which are from thence carried by an oblique ascent into the Cerebel; for when the animal Spirits ascend from the former Prominences into the Cerebel, they enter these latter first, as it were the more large beginnings or en­trances of their passage, from whence they go forward by the passage of the medullar Processes into the Cerebel.

Besides we may take notice, that when the animal Spirits are carried out of the oblong marrow into the greater natiform Prominences to be derived towards the Cerebel, they, according to their custom, (as often as they tend towards the com­mon Sensory from a double Organ of any Faculty) ought to be confounded and min­gled together before they enter the Cerebel: wherefore both the first Prominences, and also the second growing to them are joyned together with certain Processes like wings reaching one another; which connexion indeed of them, because it ought to be distinguished every where from the medullar Trunk lying under it hence, from the separation or empty space that comes between the oblong marrow and the grow­ing together of the Prominences, that cavity arises, which is by some called the fourth Ventricle, and by others the passage to it.

If it be yet farther inquired, to what end the animal Spirits are carried by this by­passage from the common passage of the oblong marrow into the Cerebel, and thence back again; I say, that this is done for a twofold respect, viz. both that the Passions or Affections of the sensitive Soul, begun from the brain, may be transmitted to the Praecordia and Viscera; then secondly, that the natural Instincts, excited in the Prae­cordia and Viscera, might be communicated to the brain. These reciprocal com­merces which are had between the brain and the Organs of involuntary Functions, ought to be instituted or performed by this private passage, lest otherwise the exerci­ses of these involuntary Faculties should very much disturb the acts of the outward Senses, or the intentions of spontaneous motions.

As to the first, it is observed, that by every passion of the sensitive Soul, as from Anger, Sadness, Pleasure, and other Affections, the Praecordia are disturbed, whe­ther we will or no; which variously dilate or constrain themselves, and so stir up in the blood divers fluctuations. Moreover, from this kind of force of the Passions the countenance or the aspects of the Face are wont to be altered and distorted after va­rious ways. The reason of all these seems to be, because when the animal Spirits, existing within the brain, are moved according to the Idea of the conceived Passion, the other Spirits also flowing within these diverting places, being in like manner [Page 109]moved, affect the Cerebel, and that coming between, the original of the Nerves, serving to the Praecordia, Viscera, and Muscles of the Face, and so the parts to which those Nerves are distributed, are also stirred up or provoked into motions answera­ble to the same passion.

But the aforesaid Prominences and their dependences serve no less also for the con­veying of the impressions of natural Instincts to the Brain, that from thence the Ap­petite and local motions might presently be retorted: by which all the exigencies or wants perceived by the Praecordia or Viscera might be supplied. When in a young one newly born the stomach crys out for hunger, the Instinct of this is carried by the passage of the Nerves to the Cerebel, and from thence by the medullar Processes to these Protuberances; and the Spirits there inhabiting, form the Idea of the impression, and carry it to the brain, wherein presently, without any previous knowledge or experience, such kind of conceptions of the Soul are stirred up, that every little living Creature presently seeks out the Mothers breasts and sucks.

But it may be objected, it does not seem of necessity we should suppose these kind of acts of the Passions and Instincts to be made apart in this by-place; for why are not the commerces of the animal Spirits ordained by the influence from the Brain into the Nerves leading to the Praecordia and so back again through the common passage of the oblong Marrow? But to that it may be readily answered, That this reciprocal mo­tion of the Spirits ought to be made through the middle region of the Cerebel, from one stage to another for the exercise of these Faculties: And therefore (since that all manner of communication between the Brain and Cerebel is performed by these Prominences) there should also be had a passage by the same way between this and the Organs of the Functions merely natural. Besides, if the rage or furious mo­tions of the Passions and Instincts should be carried in the same path in which the forces of sensible things are carried, their acts might be greatly confounded by the mutual meeting or gathering together of the animal Spirits. But this kind of Hypo­thesis concerning the Acts and Progress of the Passions and natural Instincts, shall be made more clear afterwards, when we design the Actions and Uses of the Cerebel, and of the other parts, which in like manner seem to be destinated to the same offices with these Protuberances.

In the mean time, what we have affirmed, that the latter Prominences are only Additionals or Excrescences of the former, will clearly appear to any one beholding them. But this, as we have already hinted, is seen without Controversie in the brains of a Calf, a Sheep, and some other four footed beasts; where, when the Nates are signally great, the Testes grow to the same in a very small bulk. Further, that the medullary Processes lead from these into the Cerebel, and convey the animal Spirits by this by-path, is so manifest, that none who hath carefully beheld these parts, can be able any further to hesitate or be doubtful of it. For indeed the little hairs or fibres wherewith these processes, ascending into the Cerebel, are marked, are otherwise figured and placed than those which are beheld in the neighbouring pro­cess descending from the Cerebel towards the oblong Marrow.

Moreover, either pair of Prominences do not only communicate among themselves mutually by their stretched out wings, but also another medullar Process, going cross wise, knits together the aforesaid Processes stretched out from thence into the Cerebel; and from this joyning together of them two small Nerves are produced, which bending down on either side, and being carried forward, enter the Dura Mater, and so go straight through it, till having reached to the moving Nerves of the Eyes, they go forth of the Skull at the same hole with them, going forward straight to the Trochlear Muscle of the Eye. Concerning these little Nerves it is observed, that when many others proceed from the sides or the Basis of the oblong Marrow, these arise from the aforesaid Prominences in the bunching forth at the top. The reason of which, if I be not mistaken, is this: We have affirmed, that these Prominences do receive and communicate to the Brain the natural Instinct delivered from the Heart and Bowels to the Cerebel; and on the other side, or back again, do transfer towards the Praecordia, by the mediation of the Cerebel, the forces of the Passions or Affections received from the Brain; but in either action the motion of the Eyes is affected with a certain manifest Sympathy. For if pain, want, or any other signal trouble afflicts the Viscera or the Praecordia, a dejected and cast down aspect of the Eyes will declare the sense of its trouble: when on the contrary, in Joy, or any pleasant Affection of the Praecordia or Viscera, the Eyes are made lively and [Page 110]sparkle again. In like manner, the Eyes do so clearly shew the Affections of the Mind, as Sadness, Anger, Hatred, Love, and other perturbations, that those who are affected, though they should dissemble, cannot hide the feeling and intimate conce­ptions of the mind. Without doubt these so happen, because the animal Spirits, tending this way and that way in this diverting place between the Brain and the Prae­cordia, do at once strike those Nerves as the strings of a Harp. Wherefore from this kind of conjecture which we have made concerning the use of these Nerves, we have called them Pathetical, although indeed other Nerves also may deserve this name.

There yet remains for us to take notice of the aforesaid Prominences, that either of these pairs, and the Processes hanging on them, are distinguished from the trunk of the oblong Marrow lying under by the Cavity between them; so that this Cavity or Ventricle seems to exist only secondarily, because the empty space between the aforesaid bodies, placed above and beneath, separating the same one from another, ought to come between. But this Cavity seeming to result so by accident, hath a very signal use; for in the middle of its passage a sloping aperture reaches towards the Tunnel, through which the humors sliding into either of its holes, one made more forward, the other more backward, are sent out. The more forward hole is placed between the chambers of the Optick Nerves, a little before the pineal Glandula, into which the serous heap being laid up nigh to the confines of the oblong Marrow, slides by degrees: but the other hole is opened more backward into the fourth Ventricle which is planted under the Cerebel; which hole is covered with a thin Membrane, which girding about its mouth and that of the Cerebel, provides lest the humors, derived from the fourth Ventricle, or the confines of the Cerebel, should fall down any other way than into that hole; but if at any time that little hole be broken asunder by a deluge of the Serum, the watry Latex sliding down upon the Basis of the oblong Marrow, overwhelms the origines of the Nerves, and so brings Convulsive distem­pers and meltings, and not seldom deadly, of the vital Spirits, as I have observed in the bodies of many dying of Cephalick Diseases.

CHAP. XV.

HAving hitherto continued the former Tract of the oblong Marrow, which as it were the Kings High-way, leads from the Brain, as the Metropolis, into many Provinces of the nervous stock, by private recesses and cross ways; it follows now that we view the other City of the animal Kingdom. The situation of this being remote enough from the former, its kind of structure is also different from it: yea it seems that there are granted to this, as to a free and municipal City, cer­tain Priviledges and a peculiar Jurisdiction.

The Cerebel is placed a little below the orbicular Prominences in the hinder part of the Head; where growing to the trunk of the oblong Marrow by a double little foot, it appears almost of a Spherical figure. Its superior gibbosity coheres towards the superficies to the border of the Brain by the intervention of the Pia Mater; but nevertheless it is intimately united to it, nor is there any immediate commerce be­tween this or that or their parts. There hath been spoken enough already of the figure and situation of the Cerebel, and of its various Processes, and how it is fastned to the oblong Marrow; it now remains that we proceed to design or draw out the offices and uses of it, and its several parts. Where in the first place shall be inquired into, what kind of office the Cerebel is endued with in the animal oeconomy; then when we shall descend to particulars, there are more things worthy to be noted, which will offer themselves to our consideration: viz. first the infoldings of the Ves­sels covering the whole compass of the Cerebel, and especially its hinder part, with the heap of Kernels: secondly, its folds and lappets ordained with a certain and de­terminate series, and almost after a like manner in all: thirdly, the double substance of the folds, viz. cortical and marrowy: and the concentring of all the medullary tracts in two large Marrows or middests: fourthly, either little foot or pedestal of the Cerebel made out of those two middle Marrows: and in either pedestal three [Page 111]distinct medullar Processes to be found: fifthly, the annular Protuberance made by a process of the Cerebel descending into the medullar Trunk: sixthly, some Nerves, which arising immediately from this Protuberance and other Nerves in the neigh­bourhood, which being designed for the involuntary Function, receive the influences of the animal Spirits from the Cerebel: Lastly, the Ventricle or Cavity lying under the Cerebel ought to be considered.

1. As to the office or use of the Cerebel in general: nothing of it occurs, spoken by the Ancients, worthy its fabrick, or agreeable to its structure. Some affirm this to be another Brain, and to perform the same actions with it: but if any one should have a soft and foolish Brain, I greatly doubt, if he should become wise, though he should obtain perhaps a more hard and solid Cerebel. Others place the Memory in this part, supposing the Cerebel to be as it were a Chest or Box, wherein the Idea's or images of things, before laid up, are kept apart from the incourse of fresh Species. But it is far more probable, that this faculty resides in the cortical spires of the Brain; as we have elsewhere shewn. For as often as we endeavour to remember objects long since past, we rub the Temples and the fore-part of the Head, we erect the Brain, and stir up or awaken the Spirits dwelling in that place, as if endeavouring to find out something lurking there; in the mean time, there is perceived nothing of en­deavour or striving motion in the hinder part of the Head. Besides, we have shewn, that the Phantasie and Imagination are performed in the Brain; but the Memory depends so upon the Imagination, that it seems to be only a reflected or inverse act of this: wherefore that it should be placed with it in the same Cloister, to wit, in the Brain, is but necessary; for it plainly appears, that there is no immediate commerce between the Brain and the Cerebel.

When some time past I diligently and seriously meditated on the office of the Cere­bel, and revolved in my mind several things concerning it, at length, from the Ana­logy and frequent Ratiocination, this (as I think) true and genuine use of it oc­curred; to wit, that the Cerebel is a peculiar Fountain of animal Spirits designed for some works, and wholly distinct from the Brain. Within the Brain, Imagination, Memory, Discourse, and other more superior Acts of the animal Function are per­formed; besides, the animal Spirits flow also from it into the nervous stock, by which all the spontaneous motions, to wit, of which we are knowing and will, are performed. But the office of the Cerebel seems to be for the animal Spirits to supply some Nerves; by which involuntary actions (such as are the beating of the Heart, easie Respi­ration, the Concoction of the Aliment, the protrusion of the Chyle, and many others) which are made after a constant manner unknown to us, or whether we will or no, are performed. As often as we go about voluntary motion, we seem as it were to perceive within us the Spirits residing within the fore-part of the Head to be stirred up to action, or an influx. But the Spirits inhabiting the Cerebel perform unperceivedly and silently their works of Nature without our knowledge or care. Wherefore whilst the Brain is garnished as it were with uncertain Meanders and crankling turnings and windings about, the compass of this is furnished with folds and lappets disposed in an orderly series; in the spaces of which, as in designed Orbs and Tracts, the animal Spirits are expanded according to the Rule and Method naturally impressed on them. For indeed those in the Cerebel, as it were in a certain artificial Machine or Clock, seem orderly disposed after that manner within certain little places and boundaries, that they may flow out orderly of their own accord one series after another without any driver, which may govern or moderate their motions. Wherefore forasmuch as some Nerves perform some kind of motions according to the instincts and wants of Nature, without consulting the government of the will or appe­tite within the Brain, why may it not be imagined, that the influence of the Spirits is derived wholly from the Cerebel for the performing of these? For it seems inconve­nient, that for these offices which should be performed without any tumult or pertur­bation, the Spirits should be called out of the Brain, which are continually driven into fluctuations as it were with the winds of Passions and Cogitations.

As I only imagined of the use of the Cerebel after this manner, I was led to it at length by a certain thread of Ratiocination; to which afterwards happened an Ana­tomical inspection, which plainly confirmed me in this opinion. For in the frequent Dissection of the Heads of several sorts of Animals certain Observations did occur, which seemed to put this matter out of all doubt. For I first observed, the pairs of Nerves, which did serve to the Functions, wont to be performed by the Instinct of Na­ture, [Page 112]or the force of the Passions, rather than by the beck of the will, so immediately to depend on the Cerebel, that from thence only the influence of the animal Spirits seems to be derived into their origines or beginnings. By what means the Nerves arising from the Cerebel, or receiving from it the provision of the animal Spirits, do perform only involuntary actions, shall be declared hereafter; in the mean time, for the confirmation of this Opinion, we have in readiness another Reason of no less moment.

Therefore secondly, we took notice, that not only the conformation or make of the Cerebel was ordained after a certain and peculiar manner, that is, that its frame or bulk was couched together with folds or little circles, disposed in a certain distinct series, and apt method, and proportionate within themselves, as hath been said; whence it may be argued, that the Spirits arising from hence, and flowing outward­ly, are imployed or bestowed on some certain works determinate to one thing. But further it is observed, that in all Animals, although they differ in form and kind, yet the figure of the Cerebel is always very like or wholly the same. The Brain and oblong Marrow are figured in many after a divers manner; for as we have shewed before, there is some difference of these parts found in man and four-sooted beasts: but between either of these, and Fowls and Fishes, there is a notable difference as to these parts. Notwithstanding in all these the Cerebel, furnished wholly with the same lappets or little circles alike infolded one in another, is marked with the same form and proportion; which certainly is a sign that the animal Spirits in this work­house are begotten and dispensed, as it were by a certain dimension, for certain ne­cessary offices, which are performed in all after the same manner; and which can­not be any other than the motions and actions of the Viscera and Pracordia. As to the other Faculties, of which sort are Imagination, Memory, Appetite, yea local motions and sense are exercised after one manner in those living Creatures, and after another manner in others; wherefore their brains are formed after a divers manner. But the motions of the Heart and Respiration in all endued with an hot blood, are performed after a like manner, that is, with a perpetual vicissititude of Systoles and Diastoles. Besides, another office is to be assigned to the Cerebel, and different from what is convenient or agreeable to the Brain; because where the folds and turn­ings are wanting in the Brain, they are constantly found in the Cerebel. Besides these reasons drawn from Anatomy, the Pathology of the humane Body affords many others, which confirm the aforesaid office of the Cerebel. For it oftentimes hap­pens, that cruel and horrid Symptoms infest the Praecordia and the region of the middle or lowest Belly; whilst in the mean time, the morbifick cause lyes in the Cerebel or nigh its confines. I have known sometimes men labouring only in ap­pearance with a Dyscrasie of the hinder part of the Head, who complained of fre­quent Swooning and repeated meltings of the Spirits or Deliquiums, as if they were just dying: in whom notwithstanding nothing more could be detected of the mor­bifick cause or its seat, but that the Patient perceived a great heaviness and pain in the hinder part of the Head, and that upon any sudden motion or bending back of the Head, they were ready to dye. In truth, the Symptoms which are wont to be raised up in the distemper called the Incubus or Night-mare, viz. loss of speech, and a mighty weight or load that seems to lye upon the breast, proceed altogether from the morbifick matter fixed in the confines of the Cerebel, and obstructing the passages of the Spirits destinated for the Pracordia. But indeed this Hypothesis of the office of the Cerebel shall be more illustrated and confirmed from the uses of its several parts, being rightly designed or drawn forth.

As to the parts and accidents of the Cerebel, 1. we take notice, that the infold­ings of the Vessels every where cloath the Cerebel no less than the Brain, also that the ridges and furrows of its folds intimately hide or cover it, which certainly is a sign that the animal Spirits are begotten in this other work-house of them from the watering blood, and instilled into its substance: which thing also more clearly ap­pears, because the Arteries and Veins are not only variously complicated in the super­ficies of the Cerebel, but both of them in like manner as in the Brain, send forth frequent shoots into its more inward substance; wherefore whilst the most subtil and spirituous part of the blood being carried through long windings about, and as it were serpentine chanels of the Vessels, and so sublimed into Spirits is received within; the bloody part is carried away by the shoots of the Veins sent also deeply down. Further, even as the more watry portion of the blood, destinated for the Brain, runs [Page 113]into the Choroeidal infolding; (whereby it may there lay aside its unprofitable Phlegm into the Glandula's) so for the sake of separating the Phlegm an heap of Glandula's, with the foldings of the Vessels, as it were a Receptacle fitted for this business, is placed in the hinder region of the Cerebel.

2. From the blood, after this manner cleared from Phlegm, and made subtil by a long circulation, a very pure and spirituous liquor is instilled into the cortical sub­stance of the Cerebel, which is presently exalted by the Ferment there placed into animal Spirits. For indeed we have affirmed, that the Spirits are procreated only in the cortical part of the Cerebel, as in that of the Brain: wherefore, because this kind of Cortex is wanting to the oblong and spinal Marrow, we think these parts do serve only for the exercise of the animal Spirits, and not for their pro­duction.

3. The Spirits every where produced within the cortical or exterior compass of the Cerebel, in which they are presently prepared for the work of the animal Fun­ction, are derived from all the folds into the medullar tract, and thence into two ample middle Marrows; where they keep full as it were the fountain or spring, and there like the bubling up of waters, are circulated within with a perpetual turn­ing, and from thence they continually stream forth into the parts of the nervous System proper to themselves.

4. As to the ways of Emanation it is observed, that the two middle Marrows of the Cerebel pass as it were into two pedestals or little feet, by which they are fastned to the trunk of the oblong Marrow; and for that in either little foot of it three di­stinct medullar Processes are found, all these, or at least two of them, are as it were so many paths whereby the animal Spirits stream forth from their fountain and flow back again.

5. The first of these Processes ascends into the Cerebel from the orbicular Pro­minences: the use of this we have already declared; to wit, that there may be a certain passage between these Prominences and the Cerebel, in which, whilst the animal Spirits, as in a by-path, move this way and that way, to and fro, they may transmit both the force of the Passions from the Brain by the interposition of the Cerebel to the Praecordia, and convey also the natural Instincts delivered to the Ce­rebel from the Praecordia and Viscera towards the Brain. But the second Process de­scending straight from the Cerebel, embraces the medullar Trunk, and so going round about it, constitutes the annular or ringy Protuberance, out of which the fifth, sixth, and seventh pair of Nerves take their originals; so indeed, that this Protuberance seems to be the Ware-house or Store-house of the Spirits flowing from the Cerebel, from which they may influence and be derived into the opposite passages of the Nerves. Lastly, the third process of either little foot, descending from the Cerebel into the oblong Marrow, is inserted into its trunk over against where the eighth pair of Nerves have their original; so that it should seem very likely, the provision of the Spirits destinated for this Nerve is derived also by this way from the Cerebel; then what Spirits superabound, remaining longer than this Nerve requires, they sliding down into the common belly or chanel of the oblong and spinal Marrow, increase the plenty of those parts. For this same end the smooth and pyramidal bodies are reached out of the annular Protuberance above the oblong Marrow towards the Spine, to wit, that by the passage of those Processes the Spirits of that provision or stock superabounding, might flow out partly into the beginning of the eighth pair, and partly into the common tract of the medullar Trunk.

Thus much we have spoken briefly and summarily of the Uses of the Cerebel, and of its parts and Processes. But that it may be the better understood, and also that this new thought of Theory concerning the involuntary Function of the animal Re­giment, may be more clearly illustrated, we shall here give you a more particular Order or Method of the Spirits brought forth in the Cerebel, and as it were take a view of, or muster their Arms or Forces. Further, it will seem to the purpose, that we should design or draw forth more openly the abundance or plenty of the Nerves receiving their gifts from this Fountain of the Spirits concerning the Acts to be per­formed only of the involuntary Function.

CHAP. XVI.

AFter having shewn, that the office of the Cerebel is to procreate animal Spirits apart from the Spirits begotten in the Brain, and to dispense them into the Nerves, the Executors of the involuntary Actions and Passions; there yet remains to be unsolded by what manner of oeconomy or government the Spirits inha­biting the Cerebel and made free, are busied both by an intestine Circulation, within their proper dwelling places, and also are wont to be expanded and flow out with an exterior irradiation for the necessities and wants of other parts: then these things being shewn, we shall design more particularly the Uses and Offices of the Nerves, and of some other Processes doing service to this Government.

As to the first, as the Cerebel is the other primary Root of the sensitive Soul, or the Fountain from whence the animal Spirits, being diffused through the whole sub­stance of it and its Appendix, are continued still under the same Systasis and radiant Contexture, it is to be noted, that this radiation of the Spirits from the Cerebel doth flow after another manner than the other from the Brain: because this being left to it self, is bestowed by a constant efflux or flowing out on the Organs both of the vital Function and the merely natural, and its expences by an equal continual provision of Spirits, are made up again from the bloody mass continually instilled in. But on the contrary, the Spirits flow out from the Brain, neither by such a continual course without intermission and by little and little, nor are sustained by a perpetual provision and sliding in by degrees; but both the loss of them, and their refection, are uncertain, unequal, and variously interrupted. For neither are the spontaneous Acts of the Function it self, to which they serve, performed after any constant or always the same manner; but according to exterior accidents and occasions we put them forth by heaps, and with a certain force sometimes, and again sometimes we suffer them to be wholly intermitted and unimployed. Therefore the Spirits also are in like manner supplied with an uncertain measure; to wit, they are instilled in sleep plentifully and more copiously, but waking more sparingly and with hard labour, or scarce not at all. Yea the involuntary portion it self of the sensitive Soul (which flows from the Cerebel) for that it hath a near commerce and affinity (as was already said) with the other radicated in the Brain, therefore it is wont to be much disturbed in the performing its office equally and peaceably, and being variously affected and agitated by the impulses sent here and there, or from this place and that, it is com­pelled, sometimes to contract, sometimes to extend its Systasis in the whole or in part, and so is rendred obnoxious to several Passions, and ordinarily instigated to the performing irregular and disorderly actions.

But indeed the contexture of the Spirits, or the part of the Soul irradiating the Cerebel and its Appendix, is both affected with a certain sense, and is urged into motions appropriate to it self, though divers. The sense or Sympathy belonging to this, if it be terminated within the confines of the Cerebel, is always private, nor goes any farther forward to the Brain with a more strong undulation or wavering; and because it is performed the living Creature knowing nothing of it, unless by the effect it cannot be known, for that it excites a peculiar motion. But such an affe­ction of the Cerebel is implanted in it, that by every new disposition of the Praecordia and Viscera communicated to this from beneath, also from every violent passion ex­cited within the Forum of the Brain, and so sent from above, a certain impression is carried to the inhabitants of the Cerebel: by which indeed they are disposed into va­rious ordinations for the performing these or those motions respectively.

For examples sake, so long as the tranquil region of the Cerebel, like a serene and fair Heaven, is free from all perturbation, the Spirits its inhabitants, being poured out with a pleasing sense, or as it were a certain complacency, flow within their pro­per habitations, both with a gentle circulation, and also with an equal flowing out enter the beginnings of the Nerves serving to the Functions both vital and natural: by which indeed easie Respiration, the Pulse, Chylification, and other offices of the [Page 115]same nature, are performed peaceably. But if that any trouble or molestation hap­pen outwardly to any one, from whence an impression of it is communicated to the Cerebel, presently a troublesom sense being stirred up there, it disturbs the animal Spirits in the Fountain it self, and so is wont to excite irregular motions in the Organs of the involuntary Function. For from hence the frequent alteration of the Pulse and of Respiration, also Cramps of the Viscera, and convulsive motions arise un­known to us, or also against our wills. But an impression sent from elsewhere to the Cerebel, and inducing the same kind of troublesom sense, either ascends by the pas­sage of the Nerves from the Praecordia and Viscera, or it is carried from above from the Brain by the passage of the orbicular Prominences; as shall be shewn more largely anon.

In the mean time, from these things already shewed of the passive power or sense of the Cerebel, it may be easily collected, by what means, with what order and se­ries the animal Spirits, arising from the same, are moved. But first you must distin­guish between their twofold motion. For one is customary and ordinary, consisting in a perpetual and equal efflux of Spirits; by which indeed, they flowing into the beginnings of the Nerves nigh their risings, especially of the intercostal and wandring pair, the solemn acts of the Pulse, Respiration, Chylification, and others of the involuntary Function are performed. Then secondly, the other motion happens extraordinary and occasional, which the same Spirits perform confusedly, as it were in disturbed orders: as when the Pulse becomes quicker or slower than it ought, or the Respiration unequal or interrupted; and when the other Faculties, which belong to this Class, are perverted from their regular and constant manner. But these kind of extraordinary motions are again twofold, to wit, for that its instigation proceeds from a double bound; for the impulse whereby the Spirits inhabiting the Cerebel, are compelled into an irregular action, (as we have but now intimated) is carried either from beneath, viz. from the Praecordia and Viscera; or it is wont to be trans­mitted from above, to wit, from the Brain.

As to the first, if at any time the Praecordia grow too hot, and are burnt with a fea­verish heat, presently by the passage of the Intercostals and the wandring pair of Nerves, the Spirits residing in the Cerebel, being warned of this evil, institute more frequent and stronger acts both of the Pulse and of Respiration. In like manner, if by chance the humors and sharp Juyces irritate or greatly trouble or afflict the Coats of the Ven­tricles or Intestines through the sense of this affection communicated to the Cerebel, the instinct of performing the motion is reciprocated, whereby the fibres of the parts, being contracted and wrinkled together, endeavour the shaking off of the hurtful matter. More instances might be here brought of all the other acts of the vital or merely natural Function: of which besides it may be observed, that when a sense of the trouble is immediately conveyed from the Praecordia or Viscera to the Cerebel, this affection, like the waving of waters, is either stopt or terminated there, from whence a motion, as the business requires, unknown to the Brain, is presently retorted, as when the actions of the Praecordia are altered by a feaverish distemper without our knowledge; or secondly, that sense of the trouble being transmitted to the Cerebel, for that it is more vehement, it unfolds it self more largely, and like a stronger wa­ving of waters, passing through the Cerebel, goes forward further even to the Brain, and warns its inhabitants of the evil; by which they being incited to oppose the ene­my, cause a motion of another kind: So (as hath been said) when the Praecordia grow cruelly hot, the Cerebel feeling this, makes the Pulse and Respiration stronger. But further, the Brain being warned of the same trouble, seeks and diligently re­quires cold drink and other remedies to moderate the heat. Moreover, it is after this manner also in several other actions, which though they are regular, yet being made in the Brain without any previous knowledge, they are said to be done by In­stincts merely natural; as when brute Animals, being newly brought forth, pre­sently seek for the Dams teats, and greedily suck; or Birds, without any shewing or example, build nests with wonderful Art, lay eggs, and hatch young ones. In these kind of works the Brain being taught before by none, directs fit means to the ends instituted by Nature: which indeed seems to be done by this means. The sense of every necessity being brought to the Cerebel, incites the Spirits inhabiting it to succour it; which when they are not able to do, the impression going from thence further forward, is carried to the orbicular Prominences: by which the Spirits there inhabiting, being presently struck, form the Appetite or the intention of performing, [Page 116]which being thence communicated to the Brain, it readily causes that local motions, fit for the executing of the work, be retorted. Of these we shall speak anon a little more largely, when we treat of the respect which happens between the orbicular Pro­minences and the annular Protuberance.

In the mean time, we shall take notice in the second place, that the irregular mo­tions of the Spirits in habiting the Cerebel, are wont also, by reason of the force of the affections, to be transmitted from thence to the Brain: for as often as a violent passion, as Joy, Sadness, Anger, Fear, or of any other kind, is conceived in the Brain, presently the impression of the same being brought through the by-paths of the Prominences into the Cerebel, disturbs the Spirits destinated to the vital or mere­ly natural Function in their very fountain, and for that reason presently induces no­table mutations in the Organs of those Functions.

What hath been spoken hitherto of the Cerebel being imployed about the offices of the involuntary Function only, also concerning the sense and the motions both usual and irregular of the Spirits inhabiting it, will be made more clear, if lastly we shall shew the offices of the Nerves and of the other processes, immediately depend­ing upon the Cerebel, to be no other than such as perform only involuntary Acts: which shall be briefly and succinctly done, as far as is pertinent to our purpose, because a more full consideration of them is left to another place.

CHAP. XVII.

WE have already shewed, that out of the annular Protuberance (which is a certain Process of the Cerebel) three pairs of Nerves, to wit, the fifth, sixth, and seventh immediately arise. We have said that Protuberance to be as it were a Repository or Store house, wherein the Spirits flowing out of the Cerebel, and to be derived into the depending Nerves, as occasion serves, are kept: and in the mean time, whilst they remain there, they who stream out from either middle Marrow of the Cerebel divisively, meeting mutually in this Cirque, are united together. But as the aforesaid three pairs of Nerves receive the forces of the Spirits from the Cerebel by the mediation of that Protuberance; so also the eighth pair ha­ving its rise near the insertion of the other (viz. the lowest) medullar Process sent down from the Brain, seems to derive by its passage the influence of the Spirits no less from the Cerebel: wherefore when these four conjugations of Nerves owe the Tribute of their Spirits wholly to the Cerebel, if I shall shew that all these Nerves serve chiefly and almost only to the involuntary acts of the Senses and Motions, surely this will be a signal Argument, that according to our Hypothesis, the office of the Cerebel is to beget and to dispense the animal Spirits requisite for the involuntary Functions.

Therefore in the first place we observe of the fifth and sixth conjugation of Nerves, that as this arises out of the Basis of the greater Ring, and that from its sides both in man and in four-footed beasts; the fifth pair being carried more forward, distri­butes its branches into the Glandula's of the Eyes, into the Nostrils, into the Palate, Teeth, yea and into most parts of the Face and Mouth; but the sixth pair is wholly bestowed on some Muscles of the Eyes. Further, out of the trunk of the fifth pair two shoots, and another out of the Nerve of the sixth pair bending back behind, meet together; and what is wonderful, and not before taken notice of by Anatomists, the intercostal Nerves, destinated to the Praecordia and Viscera, do make a Trunk; so that the Nerves of the fifth and sixth pair stretch out a double Ramification, to wit, one more above about the parts of the Mouth and Face, and the other lower through the Viscera of the middle and lowest Belly. But it will appear clearly to any one considering this thing more carefully, that the chief branches of either partition are imployed about the involuntary offices of Motion and Sense, of which sort those are chiefly, that either cause the passions, or perform the natural Instincts.

1. Concerning the intercostal Nerve, which (as was said) being radicated in the [Page 117]Nerves of the fifth and sixth pair, depends as to its origine wholly on the Cerebel, it is not here to be doubted but that it looking towards the Praecordia and Viscera in a man, and towards these latter only in most four-footed beasts, is bestowed on the Functions only vital and merely natural, and so confers little or nothing to sponta­neous actions. Further, forasmuch as this Nerverea ching forth into the Praecordia and Viscera of the whole Abdomen, is continued by its superior ramification also into the Eyes, as also into the parts of the Mouth and Face; certainly from hence a true and genuine reason may be given wherefore in every passion the Eyes, Face, and Mouth do so correspond with the affections of the Praecordia, often unknown to us or against our minds, that oftentimes we are compelled to betray the most intimate sense of the Heart by the countenance and aspect. Yea, hence a reason may be brought, why in sneesing, yawning, laughing, and crying the Muscles of the Face conspire so in motion with the Praecordia. Besides, when in man different from any other living Creatures besides, as we shall shew afterwards, many shoots are sent from the intercostal Nerve to the Nerve of the Diaphragma; this certainly is the cause why risibility is the proper affection of man.

But the Trunk of the fifth pair being carried more forward, and distributing its branchings through the parts of the whole Face, causes the same not only to be pathetically moved, and figured according to the affections of the Pracordia; but also produces some acts, both of motion and sensation, of another kind, which for the most part are involuntary, and so seem to depend wholly upon the Cerebel im­mediately. For example, this Nerve imparts shoots to either mandible requisite for the business of chewing: but it is very well known, that the taking in of the food at the mouth is the first and oldest business of every Animal, which indeed is taught by natural Instinct before any knowledge of the Brain. But as to the Senses, the bran­ches of this pair conduce something to the smelling, but for the most part for the knowing and chusing of savors. Hence it comes to pass, that as odors refresh the Brain by the smelling Nerves, so also they affect the Cerebel by the branch of this pair, and are wont by that means to recreate the Viscera and Praecordia. But sapors or tastes (for that they are almost the peculiar Province of this) carry whatsoever they have of pleasantness or trouble, first to the Spirits inhabiting the Cerebel, and then by their consent to the Praecordia and Viscera. Hence it is, that a Pectoral not only allays hunger, but the very first tasting of Wine raises up those that are fainting or swooning away. Moreover, forasmuch as from this Nerve certain branches serve for the taste, and others for the smell, there is contracted so strict an affinity between either of these Sensories, that nothing pleases the taste unless it be approved of by the smell: and the loss of one of these senses oftentimes causes the privation or the dimi­nution of the other.

2. Concerning the Nerve of the sixth conjugation we observe, that as one shoot is bent back for a root of the intercostal Nerve, the remaining Trunk of it being car­ried forward towards the ball of the Eye, is distributed to two of its Muscles, viz. to the seventh, proper to beasts, and to the drawing Muscle. Hence may be infer­red, that this Nerve, besides the influence of it bestowed on the vital and natural Function, serves also for the producing some pathetick motions of the Eye, to wit, such as are wont to obey the affections of the Praecordia and Viscera; so that the whole provision of the animal Spirit, which it receives from the Cerebel, it bestows only on involuntary acts.

3. The seventh pair, or the hearing Nerves, seem also to depend upon the Cere­bel, forasmuch as they take their originals out of the annular Protuberance: but the use of them is a little otherwise in man than in four-footed beasts. For in him the annular Protuberance is one, and that very big, from whose lower margin the audi­tory Nerves proceed: but in Brutes the Protuberance is twofold, viz. one greater, sent down from the Cerebel, in which the beginnings of the fifth and sixth pair of Nerves consist; then near this there is another lesser, and as it were secondary, from which the auditory Nerves proceed. This lesser and lower Ring doth not so mani­festly depend on the Cerebel, as the former; but there is stretched out from either height of it a white medullar line upon the oblong Marrow in the bottom of the fourth Ventricle: so as this seems to receive either the Spirits from the oblong Mar­row, or at least to carry into the same the sensible Species: for what use it is so con­stituted shall be inquired into afterwards; for concerning these Nerves of the seventh pair, forasmuch as some offices of them very much illustrate the government or oeco­nomy [Page 118]of the Cerebel, we shall discourse here a little more largely.

Therefore in man, who hath got a great and undivided annular Protuberance, the auditory Nerves coming out of its margin or brim, shew its stock received of the Cerebel: by which means we may see the tasks of those Nerves quadrate with the assigned government of this. We have shewn before the Processes (which in a manner may be called distinct Nerves) of the seventh pair to be twofold on either side: one, the softer of these, serves only for the sense, but the other harder seems to perform some motions. This latter Nerve, being carried without the Skull, is divided into three branches, all which serve to pathetick motions, or at least to such as are performed without consulting the Brain.

1. The first of them being bent back towards the auditory passage, is bestowed on the Muscles of the Ear. Without doubt, by the action of this, it is effected, that all Animals at the sudden impulse of a sound or noise, erect their Ears at it were to catch the sound too soon passing by. 2. The other branch of this same Nerve climb­ing over the Muscles of the Jaw, sends forth shoots towards either corner of the Eye: which are inserted into the Muscles lifting up the Eye-lids; the office of which is cer­tainly to open suddenly the Eyes at the sudden approach of any sound, and as it were to call them forth to watch, that by the stroke of the Air being brought to the Ear, the Eye might presently look about to see what is the matter, and whether there might be any danger near or not: which also all Creatures do unthought of. 3. The third branch of the same auditory Nerve descending towards the root of the Tongue, is distributed to its Muscles, and to those of the Bone Hyoides, and so actuates some of the Organs for the framing the Voice. For this reason in some measure it comes to pass, that living Creatures being astonished at an unaccustomed or horrid sound, presently putting forth an uncertain voice, cry out and make a noise. But the con­formation of these kind of Nerves in man serves for another more noted use, to wit, that the voice might fitly answer to the hearing, and that this might be set as the Echo of the sound admitted by this: so indeed, as on the other side, there be two Nerves of the same pair, the sound is received by the hearing through one, which is rendred again by the voice through the other. The common and extrinsick Echo consists in this, that a certain undulation or waving of the Air shaken or moved, be­ing stirred up, and tending towards or about, when by reason of some stop or hin­derance, it cannot go any further directly, being presently repercussed or struck back or reflected at certain angles, it is terminated contrary to the former bound. In like manner, in the hearing, the impression of the sound, or the Species admitted to the Ears by the hearing faculty of the Processes of the same or neighbouring Nerve, and being carried inwardly towards the Cerebel and common Sensory, and from thence again reflected on the vocal process, it is carried out by the Mouth. But be­tween these there is some difference, to wit, forasmuch as the outward Echo renders back the sound immediately; but the sound of the Hearing is not necessarily carried forth at the mouth presently, but that this leaves an Idea in the Head, according to which afterwards, as occasion serves, the voice is formed, which bears the type and image of that, though some time before admitted.

But here (if I may digress a little) we should inquire in what part of the Head the Ideas of sounds are left: whether only in the Brain, which is the Chest of Memory acquired as it were artificial; or whether not also in the Cerebel, which is the place of natural memory? Truly we suppose, that sounds belong to both these, as it were to distinct Store-houses. Every audible impulse being struck against the Ear, it is pre­sently carried by the passage of the auditory Process to the annulary Protuberance; but from thence it is carried, as other sensible Species, to the chamfered bodies or the com­mon Sensory; (which way it passes thither, shall be shewed afterwards) this impres­sion tending from thence farther, and being also delivered to the Brain, stirs up the Imagination, and so leaves in its Cortex an image or private mark of it self for the Memory. Further also, as the auditory Process depends on the Cerebel, and receives from it the provision of the animal Spirits: so it is most likely, that by the recess of the same Spirits the Ideas of the Sounds are conveyed also to the Cerebel; which forming there footsteps or tracts, impress a remembrance of themselves, from whence when afterwards the Species there laid up are drawn forth by the help of the vocal process, voices, like the sounds before admitted, and breaking forth in a certain ordained series, come to be made.

Hence it is usual, that musick or melody is soon learnt by some men, which after­wards [Page 119]they bring forth with exact Symphony, without any meditation or labour of the Brain; to wit, from the distinct accents of the heard harmony, the Spirits moving within the Cerebel are disposed into peculiar Schemes; according to which, when they flow on both sides into the vocal process of the auditory Nerve, they render as it were with a certain spontaneous voice, and like a Mathine or Clock with the succession of Species, the measures or Tunes of the Instrument which they had drunk in at the ears. Without doubt hence the reason may be sought, why some men learn Musick without any trouble, and others hardly or not at all. For it is observed, that some Children, before they can speak distinctly, quickly sing, and remember certain Tunes; whilst others, though very ingenious men and of excellent memory, are very Fools at Musick, and become uncapable, as an Ass for the Harp; wherefore that faculty. In the mean time, 'tis to be confessed, thatin these the Organs of the Voice are not defective; but all the fault, though wrongfully, is cast on the hearing.

But in truth the genuine cause of this defect seems to consist in this, that when in all, the audible Species go to the Cerebel sooner and more immediately than the Brain; yet in some the Cerebel being harder, and not easily yielding to the received impressions, those Species, because they could impress nothing of themselves in their passing to the Cerebel, being-carried towards the common Sensory, leave their Types or Ideas chiefly and almost wholly in the Brain: which part being still busied with disturbed motions, is less apt to keep distinctly the composures of Harmony. But in the mean time, in others the Species of audible things, besides that they are carried to the common Sensory and to the Brain, do also affect the Cerebel, especially if they are harmonically figured (forasmuch as in them there is a soster capacity of the im­pressions) with a peculiar order and Scheme of the animal Spirits: where, as the Species of the Harmony being disposed in convenient little places and cells are kept, afterwards they flow out from thence, almost unthought of, without any endeavour or labour of remembrance, but in a distinct series, and as it were in composed modes and figures, and so by blowing up the vocal processes, they constitute sweet Tunes and vocal Musick.

If that the divers ways of passage are inquired into, to wit, whereby the audible Species, being carried into the annular Protuberance, do get-both to the Brain and Cerebel; I say it is not improbable, but out of that Protuberance both a passage lyes open into the underlying tract of the oblong Marrow, and as it were the high road; as also another passage is opened into the Cerebel through the medullar processes of the same Ring. But lest there should perchance be a consusion of the animal Spirits and the sensible Species, (which indeed can hardly be avoided) if the way made for their passage should Iye open into various passages and manifold apertures; therefore concerning this it may well be supposed, that the Ideas of the Sounds pass through the Cerebel, when they are carried to the common Sensory; which region being first past, they are at length brought by a by-path, viz. through the orbicular Prominences to the chamfered Bodies: which perhaps is partly the reason, that in the Hearing the perception of the sense succeeds so late, and the impulse of the object, in respect of sight, follows so slowly.

Whilst therefore the audible Species passes through the Cerebel, in some men, it leaves in this region (for that it is of a soft temper, and fit for the receiving im­pressions) tracts and marks of it self, and so they obtain musical ears. But in others who have a harder frame of the Cerebel, they produce no tracts of the same Sounds, and therefore such are wholly destitute of the faculty of Musick.

As therefore we suppose the audible Species to pass through the Cerebel after this manner, a reason may be given from hence, wherefore Musick does not only affect the Phantasie with a certain delight, but besides chears a sad and sorrowful Heart; yea, allays all turbulent Passions excited in the Breast from an immoderate heat and fluctuation of the blood. For since the animal Spirits, serving for the motion of the Pracordia, are derived from the Cerebel; as the perturbations conceived in the Brain, the influence being transmitted hither by moving these Spirits in the Fountain it self, transfer the force of their Affections on the Breast; so the Melody introduced to the Ears, and diffused through this Province, does as it were inchant with a gen­tle breath the Spirits there inhabiting, and composes them, called off from their fury, to numbers and measures of dancing, and so appeases all tumults and inordina­tions therein excited.

From these may in some measure be known the reason of the difference, why the hearing Nerves are after a different manner in man and in four-footed beasts: for, be­cause in these there is little need that the audible Species should pass through the Cerebel, either for the reciprocations of the sound heard, by the voice, or for the impressing there the Tunes of the Harmony (for neither is Musick required, what­ever Poets feign, to the taming the Affections which move the breasts of beasts) therefore in these (I mean in four-footed beasts) the annular Protuberance dispensing the animal Spirits to the auditory Nerves, and receiving from them the sensible Spe­cies, requires not so strict an affinity with the Cerebel: yea, whenas it may suffice, that those Nerves arise from the oblong Marrow, yet the annular Protuberance, as it were a common Porch, ought to be prefixed to them; to wit, in which both the Spirits going out from either side, and the sensible Species to be carried to either, ought first to be mixed and united together, lest otherwise every sound should become double.

Among the Nerves which are seen to belong to the Cerebel, and to persorm its offi­ces, lastly follow the eighth or wandring pair, which indeed hath its rise out of the com­mon Trunk of the oblong Marrow, near the place where the last process of the Ce­rebel is terminated, and over against where the pyramidal bodies, being produced from the annular Protuberance, end: so that we think these Nerves also, by that process coming between on either side, and also perhaps in some measure through the passage of the pyramidal bodies, do derive all manner of influence of the animal Spirit from the Cerebel.

The beginning of these consists of very many fibres and filaments or little threads presently distinct one from another; to which belongs, from the very beginning of every Nerve, a noted Trunk arising out of the spinal Marrow. The description of the wandring pair of Nerves, and its protension into the Pracordia and some Viscera, are added hereafter. For the present it shall suffice, that we take notice, that for as much as this Nerve is bestowed chiefly on the Pracordia, the acts whereof are in­voluntary, and are performed without our care or knowledge in sleep as well as wa­king; and for that the same Nerve seems to receive the forces of the Spirits wholly from the nearer fountain of the Cerebel; from hence it may certainly be well con­cluded, that the government or oeconomy of the Cerebel regards only the involun­tary Function.

So much for the Nerves, which being subjected to the Government and Laws of the Cerebel, seem to obey and serve under it: among which moreover ought to be placed the sourth pair, or the pathetick Nerves of the Eyes, to wit, which arising out of the first processes of the Cerebel, come between that and the orbicular Pro­cesses; of the use of which we have spoken already. Further, we shall here take notice, that some other Nerves to be described below, for that they communicate with the aforesaid Nerves near their originals, cause also some involuntary acts to be performed; of which sort are first the ninth pair, the spinal Nerve accessory to the wandring pair, also the Nerve of the Diaphragma, and some others, as we shall shew more at large in the particular History of the Nerves.

We may also observe, concerning the Nerves but now described, which owe their stock to the Cerebel, and seem to be designed for the offices of the involuntary Function, that sometimes some of them, though of another Dominion, are compelled to obey the beck and government of the Brain: for we are wont to draw the parts of the Face, usually moved pathetically and unthought of, and also at our pleasure, into these or those Configurations or postures: we are able also in a measure to alter the motions and actions of the Pracordia and Viscera at the will or command of the Appetite. The reason of these is, partly because the Nerves of either Government communicate variously among themselves with shoots sent forth one to another, so that oftentimes the offices of the one are drawn into the parts of the other. But be­sides, we have mentioned before, that the sensible impression being inflicted on the parts of the involuntary Function, forasmuch as it is vehement, like a strong waving of water, passing through the Cerebel, affects the Brain it self. In like manner it may be thought concerning the motion which belongs to those parts, viz. that made after the ordinary manner, that it is performed by the command of the Cerebel. Not­withstanding some more severe Edicts of the Brain, by the by-passage of the Prominen­ces, belong also to the Cerebel, and determine the Offices of the Inhabitants of it to be performed at the beck of the Appetite. As every one sees that violent Passions [Page 121](whether the will be privy or not) easily do this; why therefore may not the will it self also, as occasion requires, exercise the same dominion? But in the mean time, this derogates nothing from the priviledges of the Cerebel, that it may not be called a free and municipal City, and so Mistress of the involuntary Function; for that in some few it is after the manner of the Brain: because the Brain it self in many things is compelled to serve the Cerebel and its Government, as we have already shewn, and is necessarily bound to it. For the Brain owes much to the Cerebel, forasmuch as it receives from the vital Function (which is of its Province) the provision of the blood, and by consequence the Tribute of the Spirits produced of it: so indeed that both these parts, though Principals, perform mutual offices, and as it were in a circle, require and accomplish services one for another.

CHAP. XVIII.

BEsides the aforesaid Nerves, to wit, the fourth, fifth, sixth, seventh, and eighth pair which are imployed for the performing the tacit Edicts of the Ce­rebel for every involuntary Function, and those equal in number to the rest subject to the Brain, that cause the Cerebel to have an Empire divided with it; there are also some Processes and Protuberances, which being placed before and behind the Cerebel, are its Appendixes, that are taken into part of the same Office and Ministry. The description and use of these, are already particularly delivered. But for that (as a while since we intimated) there happens a certain respect or habit between the orbicular Prominences, which is the anterior Appendix of the Cerebel, and the an­nular Protuberance, which is the other posterior Appendix of the same, and that one part is proportionate to the magnitude of the other; so as when the natiform Prominences are greater or greatest, the annular Protuberance is always smaller or smallest; and on the contrary, they who have this latter in a very great bulk, in them the other is lesser; and so for that either part seems to be a peculiar Repository of the Spirits, which belong to the oeconomy of the Cerebel, when a greater provision of them is laid up in one Store-house, therefore there resides a lesser in the other; when I say there is this kind of constant relation found between these parts, it yet remains for us to find out for what end this is so constituted.

Seeing that the animal Spirits are disposed within the several parts of the Head in distinct Schemes of Rays, through which are variously transmitted, as through Per­spective glasses, the impressions of sensible things and the instincts of motions to be performed; it easily occurs, that there are commerces had this way and that way in the natiform Prominences between the Brain and Cerebel; and that the Spirits in­habiting the annular Protuberance are Internuncii or Messengers going between, which transfer the mutual respects of the Pracordia and Viscera, as also of the parts that are wont to be pathetically moved. But if it be inquired into, what kind of commerces and respects those are which the Brain carries to the Cerebel, and on the contrary, and that either have to the Organs of the vital and merely natural Function, we shall in so difficult and very intricate a matter propose our Opinion, though with an hesi­tating and doubtful mind.

We have before intimated, that the orbicular Prominences did deliver to the Ce­rebel the forces of the Passions to be carried from the Brain to the Pracordia, and did receive from it, and communicate to the Brain the necessities of the natural Instincts delivered from the Pracordia and Viscera to the Cerebel. To these moreover we add, that the annular Protuberance serves wholly for the same offices, though after ano­ther manner; to wit, this receives the forces of the Passions, as it were at a second hand, from the Deputiship of the Cerebel, and transfers them then immediately to [Page 122]the Praecordia; and this seems to be the chiefest office of this part. Further, the same Ring receives immediately the natural Instincts from the Viscera of the middle and lowest Belly, and impresses them on the Cerebel to be conveyed further to the Brain; which kind of use it exhibits secondarily by affording only a way of passage: For indeed such Instincts having past through the Cerebel, we suppose to be formed and perfected within the orbicular Prominences, from whence being transmitted into the Brain, they draw forth requisite actions without the previous knowledge of it, or intention of doing.

Hence it may be supposed, that the annular Protuberance contains chiefly the ani­mal Spirits which perform the intestine commotions of the Affections. In every vio­lent passion of the Soul, presently the Praecordia are greatly troubled, to wit, the same being variously drawn together or spread abroad, compel the blood into divers fluctuations; but indeed a great company of the Spirits, somewhere got together and ready for Excursions in a set Battel, do perform these disorders and irregular motions of the Praecordia; and for that the Spirits can be disposed for this in no other part than here, before the beginnings of the Nerves, constituted for these offices; therefore this Protuberance in a man, by reason of the ragings of the Passions to be performed by a certain force and incitation, is far greater than in any other Animal. For as he is wont to be suddenly and vehemently disturbed, therefore the Promptua­ry or Store-house is required to be more large, in which a greater plenty of Spirits may be kept, to be bestowed on such inordinations of the Affections. Next to a man this part is greatest in a Dog, Cat, and Fox; in a Calf, Sheep, Goat, Hare, and other milder Animals it is very small.

But as the annular Protuberance seems to be the chief Organ or Chest of the Spi­rits, from whence the winds of the Passions, destinated for the exciting the Pracordia, are conveyed into the breast; so we suppose the orbicular Prominences to be a means of passage, and the very instruments whereby the instincts and necessities of the Prae­cordia and Viscera are communicated from the Cerebel to the Brain. Yea, the ani­mal Spirits dwelling in this, as a retiring place, do not only transmit these kind of Ideas or formal Reasons of the Instincts, but in some measure form and prepare them for the Brain. For when as some brute Animals, whose Brain is not imbued with a previous knowledge or practical habits, chuse and bring forth some spontaneous actions as it were with judgment and deliberation, certainly we may believe the in­tentions of these kind of acts are suggested from some other place than the Brain, to wit, from the aforesaid Prominences. Wherefore 'tis to be observed, that in some Brutes endued with an indocil or dull Brain, the Buttock-like Prominences are greatest, as may be seen in a Calf, Sheep, Hog, and many others; which Animals, as soon as they are brought to light, presently seek for their food, and what is con­gruous for them they readily know. But in a Man, a Dog, Fox, and the like, who are more apt to learn and acquire habits, these Prominences are very small; and these Animals being newly born, are furnished only with a rude and imperfect sense; besides, they are found wholly unapt to seek out their food. Upon this Observation (which holds good in most Animals which I have yet happened to dissect) as upon a Basis or foundation I dare build this kind of abstruse Hypothesis concerning the natural Instincts and Affections of the Praecordia. For as the living Creatures which are more strong in instinct, as Sheep, Hogs, Oxen, Goats, and other slow and gentler beasts, that are not obnoxious to Passions, are also less docile or apt to learn; and on the contrary, they in whom the Affections are wont to predominate, and who are furnished with a certain wit, (as besides Man, are Dogs, Foxes, and some other hotter Animals) are less powerful in Instinct: and as I have observed in the frequent Dissection of all sorts of Heads, that in those kind of living Creatures, who live rather by Wit than Instinct, the annular Protuberance, placed below the Cerebel, was notedly great, and the orbicular Prominences only very small; but in other living Creatures, where the Instinct exceeded the wit, and who were less prone to strong Affections, the orbicular Prominences were very great, and on the contrary, the ringy Protuberance exceeding small: From hence I was forced to think, that the or­bicular or natiform Prominences, where they are great, are instead of another or supplementory Brain, and the chief Organs of the natural Instincts; yet so, as these parts also serve for a way or means of passage for the transferring the Passions from the Brain towards the Cerebel and Praecordia; and that (as we have already hinted) the greater existency of the annular Protuberance is to contain plenty of Spirits re­quisite [Page 123]for the winds of the Passions; yet in the mean time, by a further tending forwards or declination of the Spirits inhabiting this, the Species of the natural In­stincts, being sent from the Praecordia and Viscera, pass through. But however the business is, because nothing can be certainly affirmed, or by demonstration, if this our Opinion please not others, at least it may be pardoned.

There remains not much more to be spoken concerning the Offices and Uses of the Cerebel and its Appendix. Concerning its substance, there is something more worthy taking notice of, to wit, that it very much differs in this respect from the structure of the Brain also, for that its cortical little circles are not founded in the stretched out Marrow, as the convolutions of the Brain; but being deeply cut in, are discontinued in their whole tract: so that the whole System of the Cerebel is as it were a cluster of Grapes compacted closely together; in which, although the Berries be contiguous, yet they remain distinct one from another, and bring forth fissures through the whole thickness of the mass. Yea the outward superficies of the Cerebel consists as it were of very many Tubercles or little Tad-stoles or Puffs which grow together on little stalks; and those stalks pass into greater branches, and they at length being bipartite or twofold, go together into two larger Marrows near the bottom of the Cerebel, in either of which are three distinct medullary Processes: of which threefold processes on either side we have already spoken. But of these con­cerning the use of the Cerebel in general, we shall yet further advertise you, that as very much of its substance is cortical, it begets animal Spirits in great plenty, to which in the circulating there is not granted, as in the Brain, an equally great space; for that there seems not to be much need of it in the animal Government. For the Spirits so produced in the Cerebel plentifully by a perpetual emanation, ought to flow outwardly for the offices of the natural and vital Function: but more inwardly for the impulses variously sent into them, they admit certain undulations or wavings, by which some occasional acts of the involuntary Function are brought forth, as is shewn before.

But as it is manifest enough, that the animal Spirits are generated within the cor­tical little circles of the Cerebel, it doth not seem needful that we should ordain their Work-house in the Ventricle subject to its frame. For that Cavity (as we have already shewn) is only an empty space, which lying under its double little foot and medullar Trunk, comes between it and the overlying bunching out of the Cerebel. But indeed there belongs to this besides a certain use, to wit, that the serous warry heap laid aside out of the Glandula's and infoldings of the Vessels, as also from the substance of the Cerebel, being made over-moist, distilling down, might slide into this Cistern. From whence, lest it should flow down upon the beginnings of the Nerves, by a restraining Membrane it is compelled into the hole of the strait Den lying under the orbicular Prominences; and from thence is received from the decli­ning aperture of the Tunnel, and carried out.

Below the Cerebel, the oblong Marrow going forward with the rest of its tract even to the hole of the hinder part of the Head, ends at length in the spinal Marrow: but in its Trunk, as yet contained within the Skull, besides the Nerves and Processes but now recited, the beginnings of the ninth and tenth pair of Nerves are also radi­cated. Of which there will be hereafter a proper place to speak, when we shall in­stitute the whole Neurology or the Doctrine of the Nerves. In the mean time, we shall take notice of the beginning of the ninth pair, which is peculiar in Man, and different from what is found in Brutes: To wit, in Man below the origine of the eighth pair, a certain Protuberance grows to either side of the oblong Marrow. Out of that four or five distinct Fibres do come forth; one or two of which binds about the Vertebral Artery passing through it, but all grow together into the same Trunk, which is the Nerve of the aforesaid pair. This Protuberance, the Pia Mater being pulled away, may be easily seen, and seems to be the Repository or Store-house of the Spirits destinated to this Nerve.

For as this Nerve is bestowed on the Tongue and its Muscles, and so conduces chiefly to the performing of speech in Man, who hath a greater and more frequent use and exercise of the voice, there seems to be need of a great provision of Spirits, plenty of which ought always to be in a readiness. But in Brutes, who have none, or a rarer necessity of the voice, such a Protuberance is wanting, because it is not required in them that the Spirits should be gathered together by heaps, as it were in a certain Porch, before the Organs of the Voice, but that it may suffice for them to [Page 124]be called forth by degrees out of the common tract of the oblong Marrow. Further, whereas some fibres of this Nerve bind about either Vertebral Artery, unless I am de­ceived, that is so ordained for this end, lest perhaps in speaking, when at any time we are more vehemently moved, the blood being stirred up, might rush upon the Brain with a torrent. For this Nerve binding about the Vertebral Artery, as it were with a bridle, and so as a Moderator not only of the Tongue, but also of the Blood, restrains its more rapid influence. After the same manner, and for no other ends, do the recurrent Nerves, destinated to some part of the same office, variously bind about the Trunk of the great Artery, as shall be shewn afterwards.

As soon as this inferior portion of the oblong Marrow is uncloathed from the Pia Mater, the pyramidal bodies come in view otherwise lying hid. These in all Ani­mals, endued with the annular Protuberance, are constantly found; also as that Protuberance is bigger, so these bodies appear more noted: but indeed in a Man and a Dog they seem like two large Nerves, which being produced out of that Ring, end over against where the eighth pair arise in sharp points. If the use of these be sought into, it is most likely, that the animal Spirits superabounding in the annular provision or store, do flow out as it were by these Emissaries, which Spirits however run into the beginnings of the eighth pair placed near, and so are bestowed by their proper means on the offices of the involuntary Function.

Although the oblong Marrow retains not its name beyond the limits of the Skull; yet it is the same substance, which from thence being continued further into the cavity and utmost recesses of the whole Spine or Back-bone, is called the Spinal Mar­row: but it is brought forth for this, that the Nerves to be distributed into the Limbs and Members more remote from the Head, might more commodiously arise out of the same medullar substance stretched out into the neighbourhood of every part. In­deed all this whole medullar Trunk, which is continued from the bottom of the Brain even to the Os sacrum, seems like the Pneumatick Chest, or Bellows of a pair of Or­gans, which includes the blast or breath destinated to every Pipe; for in like manner the animal Spirits are contained in this marrowy tract, which blow up and actuate all the Nerves hanging thereto, as occasion serves.

If you behold the origine of the whole, it seems that the whole frame both of this oblong Marrow and the spinal, is of a medullar or marrowy substance, every where growing dispersedly through the Brain and Cerebel, and then being gathered more round together in the middle of either, becomes as one heap. For the Marrows besmearing all their folds and turnings about, are as so many little rivers, which springing from thence, begin to be congregated in the middle, and to be poured out in one great one; but being from thence united, they make the oblong Marrow, as it were the chanel of the Sea, big enough for the motion or ebbing and flowing and reciprocation of the animal Spirits: which belly or chanel, however stretching it self further beyond the Skull, is increased into the spinal Marrow, as it were the bosom or process of the former.

But as the medullar tracts, besmearing the folds and convolutions of the Brain and Cerebel, unfold themselves into their middle Marrows and medullar Trunk, and so the Spirits springing dispersedly from their first fountains, congregate as it were into a certain diffused Sea; so from this Sea, causing an ebbing and flowing, or a con­tinual or very frequent influence of the animal Spirit, the same Spirits flow out into the depending chanels of the nervous System.

Concerning this part of this Marrow, which being included in the long bosom or chanel of the Vertebrae or Back-bone, and according to all their joyntings, being mark­ed with as it were knotty processes, is called the Spinal, there occur not many things worthy consideration, besides what are commonly known. The figure, situation, as also the body of this, in its whole tract, are known generally to be cloven in two, not only by Anatomists, but by every Butcher. The ramifications or branchings of the Nerves, proceeding from the spinal Marrow, are delivered hereafter. Concer­ning its conformation something peculiar occurs. For as the spinal Marrow is as it were the common passage or chanel of the Spirits flowing out of the Head into the Nerves, it may be observed, that this chanel, not after the usual manner of other passages, where many rivers flow in, doth swell up more; but on the contrary, in what place it hath more and greater Emissaries, its magnitude is increased; for in those parts of the spinal Marrow, out of which the brachial and crural Nerves arise, (or those Nerves belonging to the Arms and Legs, whose beginnings are more and larger) [Page 125]its Trunk becomes much thicker than in the rest of the frame or substance. The reason of this is, because within the medullar tracts the animal Spirits run not, nor pass through with so swift a passage, but for the most part flowing leisurely from their Fountains, when they have filled the whole space, they s [...]ay therein; and as many Spirits, upon occasion offered, are wont to be bestowed on every work, those remaining there in readiness frame certain convenient Promptuaries where they may divert themselves. Wherefore we ordinarily observe, not only of this Marrow, but of the Nerves themselves, that as often as a small branch is distributed into many shoots or suckers to be sent forth here and there, always in the very knot of the division there grows a far greater fold than in the rest of the Trunk of the Nerve; so that 'tis a wonder from whence the Nerve should acquire so in the middle of its passage a new substance and more ample bulk. But of these things and others belonging to the Doctrine of the Nerves, it behoves us to discourse in the following Chapters.

CHAP. XIX.

WHenas hitherto having beheld the several Regions of the Brain it self, the Cerebel, and medullar Appendix, and the provision and offices of them all, we have designed or drawn forth the uses and employments also of the parts and processes, and the sanguiferous Vessels belonging to every one of these; it is now time for me to stop and retire into the Port from this troublesom and intri­cate Sea of Disquisition: But indeed, because I find that I have not yet reached to the farthest shores and utmost parts; but that beyond this Sea, which we have sailed through, as yet the nervous System, and very many Creeks or Bosoms, Meanders, and highly intricate Recesses or private places in it remain to be viewed; therefore although we know it is difficult to proceed with full Sail, we have resolved to un­dertake the task of the Doctrine of the Nerves; and the rather, because without the perfect knowledge of the Nerves the Doctrine of the Brain and its Appendix would be left wholly lame and imperfect; for neither what hath already been delivered concerning them can be sufficiently understood or illustrated, nor (which I chiefly desire, and is the end of the former Disquisitions) without those things before known can the Pathology of the Brain and nervous stock be rightly instituted. And in­deed there are many things which might easily deter any one from such an under­taking: to wit, the hardness of the work, and full of hazard; which promises at first sight more difficulty and thorny labour, than pleasure or profit. Then some will object, that this Province is already so perfectly cultivated, and adorned by for­mer Anatomists, that by a repetition of the same, I may seem to have medled with a thing done to my hand. But I may readily answer to these, first, That the Anato­my of the Nerves yields more pleasant and profitable Speculations, than the Theory of any parts besides in the animated Body: for from hence the true and genuine Reasons are drawn of very many Actions and Passions that are wont to happen in our Body, which otherwise seem most difficult and unexplicable; and no less from this Fountain the hidden Causes of Diseases and their Symptoms, which commonly are ascribed to the Incantations of Witches, may be found out and clearly laid open. But as to our Observations about the Nerves, from our following Discourse it will plainly ap­pear, that I have not trod the paths or footsteps of others, nor repeated what hath been before told.

Therefore that according to our determination we may enter upon the explanation of the nervous System, we shall comprehend under this name all parts, upon which gifted with the animal Spirit, Motion and Sense necessarily and immediately de­pend, to wit, for the performing either one only, or both together in the whole Body. But these kind of parts, in respect of the Head and marrowy Appendix, are like a branching stock or imps growing out of the trunk of a Tree: for supposing that [Page 126]the cortical substances of the Brain and Cerebel are in the place of roots, and that the substances every where medullar are taken for the stock or pith; the nervous ger­mination or budding forth expanded into divarications of Nerves and Fibres, will appear like so many little branches, twigs, and leaves. Or if the Head containing in it self the chief part and power of the sensitive Soul, be taken for the body of some Luminary, as of the Sun or a Star; the nervous System shall be that radiant or beamy concretion compassing it about. Because the animal Spirits flowing from the Brain and Cerebel, with the medullar Appendix of either, as it were from a double Luminary, irradiate the nervous System, and so constitute its several parts, the Organs of Motion or Sense, or of both together, as hath been said.

The parts of the nervous System, as a radiant or beamy texture, are either pri­mary, viz. the bodies themselves of the Nerves, into which the animal Spirits im­mediately flow from the Head and its medullar Appendix; or secondarily, which are Fibres planted or interwoven in the Membranes, musculous Flesh, Tendons, and some of the Parenchyma, which also contain in themselves animal Spirits; but they receive them not but mediately and secondarily derived from the Head through the bodies of the Nerves.

We have already shewed that the animal Spirits are procreated only in the Brain and Cerebel, from which they continually springing forth, inspire and fill full the medullar Trunk: (like the Chest of a musical Organ, which receives the wind to be blown into all the Pipes) but those Spirits being carried from thence into the Nerves, as into so many Pipes hanging to the same, blow them up and actuate them with a full influence; then what flow over or abound from the Nerves, enter the Fibres dis­persed every where in the Membranes, Muscles, and other parts, and so impart to those bodies, in which the nervous Fibres are interwoven, a motive and sensitive or feeling force. And these Spirits of every part are called Implanted, forasmuch as they flow not within the Nerves, as the former, with a perpetual flood; but being something more stable and constant, stay longer in the subject bodies; and only as occasion serves, viz. according to the impressions inwardly received from the Nerves, or impressed outwardly by the objects, are ordained into divers stretchings or carryings out for the effecting of motion or sense either of this or that manner or kind.

Indeed the animal Spirits flowing within the Nerves with a living Spring, like Ri­vers from a perpetual Fountain, do not stagnate or stand still; but sliding forth with a continual course, are ever supplied and kept full with a new influence from the Fountain. In the mean time, the Spirits in the rest of the nervous kind, especially those abounding in the Membranes and musculous stock, are like Ponds and Lakes of Waters lately diffused from the chanels of Rivers, whose waters standing still are not much moved of their own accord; but being agitated by things cast into them, or by the blasts of winds, conceive divers sorts of fluctuations.

But because there is no light difference between the motions and consistency of the Spirits and of Waters, perhaps it will better illustrate the matter, if the Spirits of either kind, to wit, the inflowing and implanted, are compared to the beaming forth of divers rays of light. And so when light is let into a dark chamber, and presently inlightens the whole, we may conceive the particles of the light so swiftly diffused to be of a twofold kind; to wit, some are bodies sent from the light it self, which diffuse themselves every way into an Orb; and other luminous particles are as it were Etherial little bodies existing before in the pores of the Air, which being agitated by the former, and as it were inkindled, cause as it were a flamy, though most thin contexture, stretched out in the whole clearness. After the like manner, the animal Spirits flowing from the medullar substance into the Nerves, are as it were rays dif­fused from the light it self, and the other Spirits every where abounding in the Fi­bres, are as so many lucid particles included and implanted in the Air, which are actuated by the former, and being stirred up by them into motion, perform the acts both of the sensitive and locomotive Faculty.

That it may the better appear by what means the animal Spirits do irradiate and swiftly pass through the parts of the nervous System, both primary and secondary; so that light is scarcely carried swifter through a diaphanous Medium, than the com­munication of the Spirits is made from one end of the nervous System to the other; it will be requisite to inquire here a little concerning the Origine of the Nerves and nervous Fibres, also of their Fabrick and Conformation, to wit, what pores and pas­sages either of these bodies have, and how disposed for the passing through and com­merce of the animal Spirits.

As to the Nerves, it is manifest from what hath been said, that all of them are produced immediately out of the medullar Trunk or its processes; so that as these parts are the common and broad roads which lead both from the Brain and from the Cerebel, all the Nerves are particular paths reaching out from them on every side into the several Regions of the animated Body. Wherefore the same Marrow, which is the original of every Nerve or Sinew, forasmuch as it is drawn into a more thin thread, constitutes the matter of the same Nerve; which indeed, that it may be made more solid and compact, is cloathed with a peculiar production of the Pia Mater: for as from a Silver mass gilt or inriched with Gold, all the threads produced from it are gilded; so the same Membrane, which covers the medullar Trunk, is produced together with all the Nerves coming out from the same, and cloathes them all. Further, very many Nerves arising together out of that marrowy beginning, go forth as it were by bands; which notwithstanding, for the sake of the better pas­sage, being presently united and carried out of their bony Cloister, are included in a common Coat taken from the Dura Mater. For we suppose (which also shall be more clearly shewed anon) that all the Nerves, destinated to any parts or every par­ticular member, do arise distinctly and apart, and so remain in their whole passage. But in that oftentimes a Nerve appearing as it were one Trunk, afterwards seems to go into many branches, it is because those branches being indeed singular, and divided in the whole passage, are collected as it were into one bundle; for sometimes we have separated those Nerves, seeming to grow together as it were into one rope or cord of a Nerve, one from another, dividing them to their very original; for neither otherwise could the Instincts of the Motions to be performed be carried so respectively to these or those parts, separate one from another, to which the branches of the same Trunk belong.

The passages of the Nerves are not bored through as the Veins and Arteries; for the substance of those are not only impervious to any Bodkin, but no cavity can be seen in them, no not by the help of Spectacles or a Microscope. As to what belongs to the smelling little Pipes, they seem to be so made, not for the passage of the animal Spirits, but that some serosities might slide down that way: but the Spirits themselves are carried in the sides, and not in the cavity of either Pipe; but the substance of the other Nerves appears plainly firm and compacted, that the subtil humor, which is the Vehicle of the Spirits, may pass through their frames or substances, even as the spirits of Wine, the extended strings of a Lute, only by creeping leisurely through. Hence it may be argued, that because the animal Spirits require no manifest cavity within the Nerves for their expansion; neither is there need of the like for them within the substance of the Brain; but that the Ventricles, commonly so called, ought to be deputed to some other office than this.

But the Nerves are white, smooth, and round bodies: within the Skull and nigh their beginnings, being as it were only covered with the Pia Mater, they are soft and easily broken; without this, for that many of them are for the most part gathe­red together, and also cloathed with the Dura Mater, they become somewhat hard and more tenacious. The Nerves themselves (as may be discovered by the help of a Microcosm or Perspective-glass) are furnished throughout with pores and passages, as it were so many little holes in a Honey-comb, thickly set, made hollow, and con­tiguous one by another; so the Tube-like substance of them, like an Indian Cane, is every where porous and pervious. Within these little spaces the animal Spirits or very subtil little Bodies, and of their own nature ever in a readiness for motion, do gently flow; to which is joyned, both for a Vehicle, as also for a Bridle or stay, a watry Latex, and that it self of very subtil parts, This Humor diffuses with its flui­dity the Spirits through the whole nervous System; also by its viscosity retains them, that they be not wholly dissipated, but as it were in a certain Systasis and continued Series; for it seems, that without such an Humor the Spirits could not consist within the nervous stock, but they would vanish away into Air. Further, the same Humor is no less required for the passing through of the sensible Species: because the animal Spirits, we suppose, like the rays of Light, to be diffused through the whole nervous System; and those rays, unless the humid particles of the Air be mingled with them, do not easily transmit the forms or images of things; as is obvious in an Optick Scene, which is hid or shadowed by the clear beams or brightness of the Sun. And in like manner, from the defect or depravation of the nervous Juyce, we can readily shew, that the inordinations of the animal Spirits, and oftentimes most horrid distempers of the Brain and the nervous stock do arise.

This nervous Juyce being derived from the Brain and Cerebel into the medullar Appendix, is carried from thence by a gentle sliding down through the Nerves even into the whole nervous stock, and waters its whole System. Upon the equal ema­nation of this depends the expansion of the animal Spirits through the whole; and the substance of these, yea the Hypostasis of the sensitive Soul it self is founded on the diffusion of the same humor. The animal Spirits being left to themselves, follow the motion of this Juyce, and flowing together with it in the same course, are plea­singly or quietly expatiated; but in the mean time, as occasion is offered, the same Spirits, as a breath moving upon those waters, conceive other spreadings abroad, and those more rapid. For as in a River, from winds or any thing cast in, divers undulations or wavings are stirred up; so the animal Spirits being raised up by ob­jects for the performing the offices of sense and motion, do tend this way or that way to and fro within the nervous stock, and are agitated hither and thither by other means.

But to return to the parts of the nervous System, besides the Nerves themselves, Fibres also being dispersedly interwoven in the Membranes, the musculous Flesh, the Parenchyma, and other parts, and united in the Tendons, are the Organs of sense and motion. Yea, the acts of their faculties are principally and more immediately executed by the Fibres than the Nerves; for they, by drawing together the Muscle and other motive parts, cause the motion it self; but the Nerves only carry from the Head the instinct for the performing of that motion. In like manner, in Sensation the Fibres receive first of all and immediately the impressions of sensible things, and express the same (as musical strings do the strikings of a quill or fingers) by an in­trinsecal modification of the Particles, and represent the various approaches of the object by the like motion of the Fibrils, as by a moveable and fluid Character, whose Idea the Nerves transfer only to the Head.

Concerning the nervous Fibres it behoves us to inquire from whence they have their rise? For it appears plainly, that they arise not immediately from the Head or its medullar Appendix; nor is it less improbable, that they are produced (as 'tis common­ly said) from the Nerves: because what is asserted, that the Fibres are productions of the Nerves, and little bits or pieces of them torn off, as it were into hairy branches, seems unlikely; for that the Fibres in some parts, being placed nigh, exceed in their bulk the magnitude of the Nerve that is brought to that part, at least an hundred-fold: which thing appears clearly from the Tendon of every Muscle, which being made up of united Fibres, is observed to be far greater than the Nerve inserted to it. And indeed for almost the like reason we are induced to think the nervous Humor it self also, whereby the Membranes and musculous Fibres are wont to be watered, to be derived unto them not by the only means and passage of the Nerves; because it is heaped up much more plentifully and in more abundance than can be carried thither through those narrow passages, as appears clearly in Ulcers of the Kings Evil, or in Impostumes or Wounds of the Tendons and nervous parts, in which a glutinous Humor drops forth in so great abundance, that all the Nerves of the whole Body could scarce be able to supply it.

Wherefore concerning these, it seems that we may affirm, that the Fibres are not continued portions of the Nerves broken off into little hairy strings or Capillaments; and that all the Fibres originally proceed not from the Nerves, because some of them, viz. those interwoven to the Heart and its Vessels are of equal birth with the Nerves themselves, and coexist with them together from the beginning. However most Fibres, as to their production, depend upon the Nerves; and all, which way soever brought forth, receive constantly from the Nerves the forces and supplements of the animal Spirits, and also the Instincts of the Motions to be performed by them.

Therefore to recount the births or kinds of Fibres; they are first either spermatick and first begotten, the rudiments or first beginnings of which being of the like anti­quity as the Heart and Brain, placed in the Conception, afterwards leisurely increase; to wit, such are, as hath been said, those in the Heart it self in its depending Vessels, the Membranes and some other parts, which form the first stuff or threads of the Embryo: or secondly, other Fibres are produced secondarily, and by a second birth; of which sort chiefly are such which are interwoven into the parts taken for the com­pleating of the animal Fabrick, and especially those termed Sanguineous, which we think to be begotten after this manner.

The Heart and Brain, with the Arteries and Nerves hanging to them, are primi­genious parts, and highly original; but these, for the second birth of others, and [Page 129]for the nutrition and increase of all the sensitive parts, distribute a twofold humor: viz. one spirituous and endued with very active Particles which perpetually flow, though but in a very small quantity, through the passages of the Nerves from the Brain and Cerebel; and the other slow and softer, which being every where laid aside through the Arteries from the bloody mass, is rendred more plentifully. This latter being of it self dull and thicker by much, is actuated by the former, and being im­bued by it, as by a certain Ferment, acquires strength and power of growth or ve­getation. But indeed the nervous Juyce, forasmuch as it diffuses with it self the animal Spirits, imparts to every part, besides the faculties of Motion and Sense, the determinations also of form and figure. Further, whilst that, being joyned to the other arterious humor, is disposed into the substance and matter of the member or part to be nourished, it forms some tracts as it were, to wit, the Fibres themselves, in which the animal Spirits, coming together with them, reside and are expatiated. These twofold or twin humors, coupling together in every sensitive part, constitute a liquor truly nutritious, to wit, which is both spirituous and nourishable. And in truth, both these Juyces, viz. the nervous and arterious, being married together, are as it were the male and female seed, which being mingled in a fruitful womb, pro­duces the plastick Humor, by whose virtue the living creature is formed and increases. Hence may be observed, as the particles of the spirituous liquor, or of the other more watry juyce (viz. this latter being supplied from the Arteries, or that from the Nerves) are strong or excel, as to their properties or powers, all living creatures become more or less nimble, active, and ready to any motion and labour. Besides, from the default or depravation of the one and the other humor excelling, the sorts or kinds of this or that disease are excited; concerning which, and also what belongs to the explication of the nutritious Humor, we may perhaps have some other time occasion to discourse.

The animal Spirits which enter and fill the ordained series of the Fibres as so many little places, flow thither by the passages of the Nerves; notwithstanding the Spirits which are seated in the Fibres, interwoven with the musculous stock, receive nou­rishment, yea and as it were auxiliary forces, from the arterious blood there plenti­fully flowing: whereby indeed both the Spirits themselves acquire for the performing of Motions a greater force and as it were elastick; so that their force being stirred up by a strong endeavour, it seems like the explosion of Gun-powder; and also the same Spirits being continually consumed within the Muscles more profusely than is wont to be in the Membranes and other parts, are in some measure made up or re­paired from the bloody sustenance: because whenas the arterious Juyce joyns more plentifully with the nervous flowing within the sanguine [...]s parts, it may be well thought, that it also lays upon the Spirits brought thither with it, as it were some nitrosulphureous particles, and intimately fixes them on them; and so, by reason of this Copula, highly flatuous and apt to be rarified, the Spirits themselves become there more active, so that in every motive endeavour, whereby the Muscle is sud­denly intumified, they, as if inkindled, are exploded. Moreover, a sudden refe­ction of the consumed or wasted Spirits, after great exercise or labour, is for this reason also performed by the blood; for that the spirituous particles being left and forsaken by motion, presently a new Copula of the same kind of matter, apt for ex­plosion, is joyned to them. For it is not possible, that the immense loss of Spirits which happens in hard labours (if they were wholly destroyed) in so short a time, should be able to be restored by supplements coming only through the Nerves, We shall discourse more largely of these things, if at any time hereafter we shall treat of the Motions of the Muscles.

The animal Spirits being disposed within the several Muscles, according to the series of Fibres, seem as it were so many distinct Troops or Companies of Souldiers; all which being set as it were in a Watch-tower, are ordained, as a new impression is carried to them by the Nerves, either from the objects outwardly, or more inwardly from the Head, forthwith into various forms and peculiar orders for the performing of motion or sense of this or that kind. The carriage or behaviour of these is worth the seeing in an animal newly killed and its skin taken off. For when life perishes, and all the force of the Spirits flowing in through the Nerves hath quite ceased; yet the Spirits implanted into the whole Body breaking forth from the Muscles, still move and shake them, and force them into several Convulsions and trembling motions.

From what hath been said we may gather, what the disposition or order of the [Page 130]animal Spirits may be in the whole animal Body: to wit, those procreated in the cor­tical substance both of the Brain and Cerebel, are congregated into the middles of either, as it were into distinct Empories or Marts; and an expansion being made in either, they cause certain interior powers of the sensitive Soul to be exercised; yet the same Spirits, affecting more room, enter the oblong Marrow (as it were the Chest, as hath been said, of a musical Organ) and sill it full; within which flowing, they carry to and fro the impressions of sensible Things and the Instincts of Motions. From the oblong and spinal Marrow the same Spirits, unless when they are otherwise busied, tending outwardly, flow towards the several parts of the whole Body; which notwithstanding wandring so out of doors, because they pass through very strait ways in their passage, [...]o wit, the slender bodies of the Nerves, they break not forth in heaps, or in a thick troop, but only contracted orderly, and as it were by bands or divisions: but they being carried beyond the extremities of the Nerves, and there possessing the Membranes, Muscles, and other sensible parts, dilate themselves as it were into a most ample field, and with a very diffuse Army they dwell in the Pores and passages of the Fibres planted every where about; where also being endowed from the blood with new food, they become more lively and more expeditious or ready for the designed offices.

Here perhaps it may be demanded, how the animal Spirits, diffused in such nume­rous troops through the habit of the Body, are able to be supplied by so strait chanels of the Nerves? To which we reply, That those which reside more outwardly do not quickly evaporate, nor are remanded back by Circulation: wherefore when all the Fibres are filled by an influx of the Spirits made by little and little from the begin­ning, very small supplements suffice to repair their expence: For neither are those dwelling more outwardly, for that they are repaired by the bloody food, much con­sumed, though in frequent action.

Hence may be noted the difference between the distributions of the blood and ani­mal Spirits. That Latex, because it is reduced in a circle, its Vessels are in the whole passage proportionated as to the bulk of the Trunk and the branchings sent from it, to wit, so that the branches of the great Artery, being carried from the Heart, con­tain at the least so much of the blood, as the shoots reaching forth from them, into all the parts. But because the animal Spirits, being once begotten and carried more outwardly, subsist longer there, and evaporate very slowly and by little and little; therefore the Vessels carrying them, viz. the Nerves, in respect of the Fibres re­ceiving them, are made much lesser in proportion; lest perhaps by too great a sup­plement of the animal Spirits, and the too thick gathering of the fresh ones still into the nervous parts, the Army of the Veterans, before instructed, should be confound­ed, and so the orders of all being disturbed, the exercises of the animal Function should be performed any how. For indeed when at any time the Spirits are made too sharp, so that being therefore struck as it were with madness, they rush upon the nervous System with tumult and impetuosity; from thence a great unquietness and continual throwing about of the Members are wont to be excited, to which some­times madness and fury succeed.

In the order and ordination of the animal Spirits, such as was but now described, the Hypostasis or the Essence of the sensitive Soul consists, to wit, which is only a certain Systasis or shadowy subsistence of those Spirits, which like Atoms or subtil Particles, being chained and adhering mutually one to another, are figured together in a certain Species. Moreover, the faculties of the same Soul depend upon the va­rious Metathesis and gesticulation of those Spirits within the aforesaid Organs of the Head and nervous System. But the consideration of this Soul and its powers requires a peculiar Tract, which hereafter (God willing) we intend; in the mean time, our Method demands of us, that (according to our weak skill) by the cense or numbering of the Nerves, being particularly made, we should deliver an exact Neurology or Doctrine of the Nerves.

But for that in the premised general consideration of the Nerves and Fibres, there was mention made of the nervous and nutritious Juyce; notwithstanding what be­longs to their powers and natures, hath been neither fully nor clearly enough deli­vered; therefore we will a little divert here, and make it our business to inquire what sort of Juyces and Humors are carried into the parts of the animated body for their nourishment, and by what ways or passages: then this difficulty being removed, a plain and easie way leads into the Doctrine of the Nerves.

CHAP. XX.

SInce the Circulation of the Blood was made known, and it hath been plainly made appear, that it did no where stagnate and stand still long, but was carried in a reciprocal motion, always as in a circle; it began to grow doubtful, whe­ther its Latex is nutritious or not. For besides, that the more rapid course of the blood, as of a torrent, might seem to wear the banks which it flowed between, and to carry away some Particles from them, rather than to be able to affix any thing to them; the substance it self also of the blood, for that it is more torrid and uneven, is thought to be altogether unfit for nutrition. Wherefore that a Juyce may be found more convenient or fit for this office, the passages and hidden recesses of the Nerves are to be viewed; and as a certain Latex is found to flow within their Pores and pas­sages, presently the blood being rejected, that nervous humor is gifted with the title of nutritious: but yet by what right, and after what manner nutrition is performed, shall be our present purpose to inquire.

And here first of all, that we may take the part of the blood, it will be easie to shew, that there is matter contained in it fit enough for the nourishment of the body, and a sufficient store of it. For besides the sulphureous substance of the blood, which within the fire place of the Heart, with a continual inkindling, and by that means deflagration in the Vessels produces life, and in the more perfect Animals heat, there is found also a certain other humor soft and alible, which in the Circulation, being distributed through several parts of the Body, by increasing them adds nourishment and bulk: yea the deflagration it self of the blood, plainly as a Kitchin-fire in dressing meat, as it were boils and prepares this humor, whereby it more easily is assimilated into the substance of every part to be nourished. Hence it comes to pass, that by reason of a defect of heat in the blood, no less than of excess, nutrition is often hin­dered. But that this kind of alible Juyce is contained in the bloody mass, the Ana­tomy or spontaneous Analysis of its Latex sufficiently declares; for the extravasated blood, when it goes into parts of its own accord, this liquor being disjoyned from the purple thick part, and swimming a-top of it, appears clear or limpid; but by reason of its more thick contents, to wit, the nutritious Particles, like the white of an Egg, it is easily made thick, and grows white by a gentle heat: which thing ap­pears by this familiar Experiment, to wit, if you shall evaporate a little of it only in a Skillet over the fire, the whole liquor will presently grow together into a white Gelly. By this liquor, as the blood is more or less imbued with it, living Creatures grow and become more fleshy or lean: for both the blood of younger Animals being loosned from cold, is wont to shew much more of this kind of white than more ancient or older Creatures; and we may take notice daily at our Tables, that very much of this kind of Gelly comes out of the flesh of a Lamb or Calf being boiled or roasted, and nothing almost from Mutton or Beef, especially if old. Therefore we may lawfully suppose, that the blood is truly nourishable; and that the whole, or at least the greatest part of the matter, for the adding bulk or substance to every part, is dispensed from it: but if at any time it be defective in this its office, that happens not out of the natural unfitness of it, but because its disposition is sometimes depraved, and as the Stomach labouring with some vice, rejects or perverts the Chyle to be cooked by it.

But the blood, as it is not the only and alone humor, which is distributed in the animated Body, so neither seems it able to perform alone and of it self the whole office of nutrition. For besides that, being diffused through the Arteries and Veins, another Latex is every where dispensed from the Head through the Nerves; which shall be shewn to afford something at least to nourishment.

As to the first, there are many reasons which declare that kind of humor to be in the Brain and nervous stock, and to abound in their whole passages. For unless the animal Spirits, continually flowing out, should be founded in such a Latex, which is their Vehicle, they would not be contiguous or joyned, nor able to continue and [Page 132]knit together the Systasis of the sensitive Soul. For if Hippocrates did observe long since, that Cramps and Convulsive motions were produced from driness and emptiness, that perhaps might happen by this means: to wit, because the humor in the Nerves or Fibres being deficient, the Spirits distracted one from another, were separated; which notwithstanding, that they might still retain their mutual embraces, and as it were folding of hands, bend the containing bodies, and very much contract, and so force them into Convulsions. Besides, Wounds and Impostumes of the Tendons and nervous parts seem to witness the diffusion of the nervous Juyce, either of which drop forth a thin Ichor, and wholly unlike to the mere bloody Excretion: no less may be argued from the Ganglia and Evil running Sores. In time of sleeping the aforesaid humor is wont to flow more plentifully into the Brain and Nerves, and to obstruct their passages; and therefore yawnings and stretchings come frequently upon those awaking, that its reliques might be shook off. Lastly, we might readily shew, that from the depravation of the nervous humor, Melancholy, Madness, and some wonderful Convulsive distempers proceed. But it may be objected, that there is no such kind of humor, because the Nerves being cut asunder, it is not perceived to flow out; and that the Nerves being also bound, they do not swell above the Liga­ture, as Arteries and Veins. But it may be answered, That the liquor flowing in the nervous stock, is very subtil and spirituous, and which, by any striving or wrinkling up of those parts, when they are roughly handled, may easily evaporate and be blown away or dispersed unperceivably. Then further, 'tis observed in the Whelps of some Animals newly litter'd, who have as yet that juyce viscous, and not easily to be dis­persed, and that have their Nerves greater, if they be bound hard together with cords, they will swell above the Ligature.

Therefore seeing it appears, that a certain Humor doth creep through the blind Pipes and passages of the Head and of the Appendix, both medullar and nervous, it behoves us next of all to inquire from whence that comes thither, and whither it tends; and lastly, of what kind of nature and use it is. Concerning these first it ap­pears, from what hath been said, that the aforesaid Latex, serving for a Vehicle of the animal Spirits, is perpetually instilled, together with them, from the blood wa­tering the exterior confines of the Brain and Cerebel, which from thence, passing through the medullar Trunk, is afterwards, with a gentle spring, poured through the whole frame of the nervous System; so that the first fountains of the nervous humor are in the Brain and Cerebel. But further, to this Juyce conveying the forces of the animal Spirits, and supplied only from the Head, there joyns a certain other humor, as it were auxiliar in the whole passage, and restores and refreshes it other­wise about to grow deficient.

We think that these kind of supplements and subsidies, which happen to come from elsewhere to the nervous Juyce flowing from the Head, are received and ad­mitted inwardly from the sides and extremities of the medullar and nervous System. We have already shewed that an humor, as it were secondary, is instilled from the blood watering these parts in its whole passage; because the Arteries follow not only the medullar Trunk, but also the greater Trunks of the Nerves in many places, and insert into them sanguiferous shoots. Besides, forasmuch as the animal Spirits flowing within the nervous stock for the performing of sense and motion, tend to and fro, and so bear a double aspect; it is probable also, that the liquor watering the Nerves, as it most commonly tends forward, so sometimes backward; and so that the extremities of the Nerves, implanted in some parts, imbibe from them the hu­mor, at least some Effluvia's, with which they are satisfied, and oftentimes transfer them into the Brain it self. Certainly there is no doubt, that the Fibres and ner­vous Filaments or threads which cover the Sensory of taste, and the Viscera serving for Concoction, do immediately receive some tastes of the taken in food, from which supplies are carried to the Brain it self in great hunger and saintness of Spirits. Because if at any time the Spirits inhabiting it, being exhausted very much with heavy and long labour, begin to sail, a most swift refection is performed, Pectorals or Cordials being scarcely swallowed, and long indeed before the alible Juyce can be able to reach to the border of the Brain by the passage of the blood. Moreover it is most likely, that not only the benign Effluvia's of the aliment are received by the extremities of the Nerves ending about the Viscera; but also by this way, that often­times an infestous matter, and in a manner malignant, is communicated by the Nerves and their passages to the Head. But indeed the preternatural Juyces heaped up about [Page 133]the Hypochondria, the Spleen, Womb, and other Bowels emit vaporous little bo­dies, which not only infect the bloody mass, and distemper the Head by that means, but they climb to the Brain more immediately by the passage of the Nerves, and strike it with an heavy ill. For from hence in part it comes, that Hypochon­driacks and Hysterical people are so cruelly punished through the Symptoms stirred up in the Brain and nervous stock for the faults of the lower Bowels; hence it is, that little Pills of Opium, being scarcely dissolved in the Stomach, cause a Torpor or heaviness. But here is no place to discourse more largely of these. It behoves us to consider what remains, the Springs of the nervous Juyce, the Auxiliaries but now detected, and its Virtues and Influences.

Concerning the nervous Liquor we shall inquire what that doth in its passage, to wit, whilst it flows within the Marrows or middles of the Brain and Cerebel, the me­dullar Trunk and the bodies themselves of the Nerves: secondly, then for what uses, it serves, when being sliden from the ends of the Nerves, it is spread abroad on the secondary parts of the nervous System.

1. As to the first, whilst that of the nervous Liquor passes through the Head, and either of its Appendix, its chief office seems to be for a Vehicle of the animal Spirits, which indeed it carries along with its diffusion, and contains them under the same Systasis. Yea, this Latex shews various Schemes of the Spirits for the performing of sense and motion; even as the humid Particles of the Air pass through the Optick Configurations of the Rays of Light. Also moreover, the nutrition of the aforesaid parts and accretion or growth into a greater bulk, depends in some measure upon the nervous Juyce watering the same, as shall be shewed by and by.

2. But the greatest question is concerning this Liquor being diffused beyond the ends of the Nerves upon the secondary parts of the nervous System, and in the pas­sages of them on the whole Body; to wit, whether such a Juyce be nourishing of all the solid parts, or of some of them by themselves, as Authors variously think; or to what other office it is destinated.

Concerning these it first appears, that the Brain and Nerves, with the Juyce flow­ing out of them, contribute matter, or at least some influence to the work of nutri­tion; the which if it should chance to fail (a sign of which defect is, if the animal Faculty falters in part) the nourishment there is wont presently to be hindred or perverted. This is plainly seen in the Palsie, excited from an evident cause, with­out any previous Dyscrasie of the blood, where suddenly an Atrophy follows the privation of motion or sense, or of both together. Further, in the Scurvy, where the taint hath corrupted the nervous Juyce, when the sick begin to be afflicted with the Vertigo and swimming of the Head, and with wandring pains, Convulsions, and a frequent loosning of the Members, the flesh falls presently away, as in a Con­sumption, and without any fault of the Lungs, the sick wither away, as if distem­pered with a Phthisis. It is a vulgar observation, That from the immoderate use of Venus, also from an inveterate Gonorhrea, from Strumous or running Ulcers, and other Impostumes, by which much of the nervous Juyce is wasted, a leanness or wasting of the whole Body is produced. Certainly, if I be not deceived, there are some Atrophies, yea, and sorts of breakings out, which seem to depend wholly upon the defect or the evil dispensation of the nervous Juyce, when the blood, as to its quantity and disposition, is not much in fault. Lastly, the consideration of some Diseases and Symptoms so plainly confirms the diffusion of the nervous Liquor and its great influence on all the parts, that there is even left no room for doubting.

Also no less doth the curing of some Diseases and the use of Remedies confirm the same. For from hence a reason is taken, wherefore Cephalick Plasters oftentimes yield such signal help in the Phthisis; not because they stay the Catarrh of the Serum falling down on the Lungs, (as the common people think) but because by corroborating the Brain they restore the disposition of the nervous Juyce, before vitiated. For this cause it is, that some diseases being stirred up by the fault of the nervous Liquor, of which sort among others are Cancrous and Strumous Ulcers, or such as come of the Kings-Evil, are hardest of all to be cured; because the morbid tincture of the Brain, and of the Latex watering it (whether it be innate or acquired) is not easily mended: yet sometimes when the root of the disease, lurking in the Brain or nervous stock, is ta­ken away by the help of Nature it self, or by Chance, by the use of some remedy; presently the Symptoms of other parts, though neglected in the whole, vanish, not without the suspicion of a miracle. But how much the alteration of the Brain serves [Page 134]for the curing of some most grievous diseases, some instances taken from the Farriers Art will clearly shew.

For when many Medicines and Methods of Administrations are wont to be tryed in vain for the curing the stinking disease in Horses, commonly called the Farcy (which Helmontius asserts to be like the French Pox, and the Author of its Contagion) the most certain means of curing (which I have very often known to be applied with good success) consists in this; that some sharp Medicines, of which sort are Hearts-ease, Water-Pepper, Ranunculus or Crowfoot, and the like, which very much abound in volatile Salt, being bruised into a mass, and put into the Ears of the dis­eased Horse, and kept there for twenty four hours: it is scarce credible by what means all the Ulcers are presently dryed up, and the disease healed, as it were by In­chantment, is quickly profligated in the whole. For since this Application is made far from the affected parts, without any alteration of the bowels or the blood, it should be so healed at a distance; certainly the cause of such an Energy must only be, that by this kind of Medicine the Dyscrasie or evil disposition of the Brain and nervous Juyce is taken away, and so the first root of the sickness being cut off, the shoots and fruits presently wither. It were worth our labour to try such kind of Experiments also in our Medicines. Yea it may be well suspected, that such a way ought to be ordered for the common Cure of the Kings-Evil. Among our Country-men, as de­livered from our Ancestors, it is thought that the seventh Son, or he that is born the seventh one after another in a continued series, can cure this disease by stroking it only with his hand; and truly I have known many, whom no Medicines could help, to have been cured in a short time only by that remedy. Few doubt but that this disease is wont to be cured often by the Touch of our King. The reason of such an effect (if it be merely natural) ought to be assigned not to any other thing than that in the sick (especially those of ripe age) the Phantasie and strong Faith of the hoped for Cure induces that alteration, or rather strengthning to the Brain, whereby the mor­bid disposition radicated in it is profligated. But I shall return from whence I am digressed, to inquire what the nervous Juyce contributes to nutrition.

2. I say therefore secondly, although nutrition depends in some measure upon the influence of the nervous Juyce, yet it is highly improbable, that all the several parts of the whole Body should be nourished only by this provision. For besides that this were to impose upon the Government of the Soul it self, and its primary Organs, the cooking office of nutrition wholly unworthy the excellency and dignity of those parts; it seems also that the nervous Liquor should be altogether unfit for the administring to this Province: because when oftentimes immense expences are made of the ali­ment to be assimilated into the substance of the solid parts, especially by immoderate sweat, also by continual labour and exercise, which Country-men and Labourers daily use, it is not possible that such losses should be repaired only by the nourishment sup­plied, or sent through the small passages of the Nerves.

When I had long and seriously considered with my self concerning this thing, what I at length thought, I shall tell you freely, and without any covering, or making any reflection, or blaming the Opinions of others. It seems first, that the nourishing matter of the whole Body is distributed into all parts from the blood through the Ar­teries; yet it may lawfully be thought, that the conversion of this matter into nu­triment, and the assimilation of it into the substance of the part to be nourished, is performed by the influence and help of the nervous Juyce, as it were of a certain spi­rituous Ferment. As to the first: we have already noted, that the sanguiferous Ves­sels do not only follow almost every where the Muscles and Bowels, but also the Head and its Appendix, yea the Membranes, Bones, and Nerves themselves, and affix to them all thick shoots, as so many little chanels, for the receiving the nourishment. Moreover, as there is a purple crassament or thick substance in the blood, whose sub­stance stuffs and nourishes the Pores of the Parenchyma of the Muscles; so there is a whitish Gelly, by which the Membranes and the whiter parts seem to increase. Be­sides it may be observed, that the blood it self increasing, contains in it self fibres and small threads, such as are interwoven in the Muscles and nervous parts; and if the same stand long in any Vessel, it is presently coagulated into longish, white, and hard crusts or bits, whose substance is plainly fleshy; so that the blood produces flesh of it self, though the same be rude and unformed: wherefore the configuration and the apt disposition of the nourishing matter, supplied from it, depends on the coming and Energy of the nervous Juyce: but after what manner this is done, we shall endea­vour now to shew.

After the web or stuff of all the parts is laid, it is required then that they be both drawn forth in due proportion, and grow in substance, and also that the little spaces which are left by reason of the Effluvia's perpetually falling off, may be continually filled with the nourishing substance cast in. In these two things the business of nutri­tion chiefly consists; for the performing of either of which the blood affords matter, and reaches it forth (as was said) in the circulating to the several parts of the con­crete, and as it were stands at the doors of the part to be nourished: yet, that this matter may be rightly disposed, and its particles, to wit, the thick and thin, saline and sulphureous, and others of a several nature, separated one from another, may be imployed with some choice to the destinated uses, there seems need of a cer­tain directing faculty, and as it were plastick virtue, got somewhere else than from the blood it self. For indeed the blood being destitute of animal Spirits, is unfit for the performing these offices. Wherefore, for that it appears there doth lye hid in the nervous stock, a certain juyce, and the same being gifted with animal Spirit to be diffused to all parts, how can we suppose less but that this subtil and spirituous Li­quor, every where meeting with the arterious, which is duller and thicker, actuates and inspires it, and as it were ordains it for the performing the designed work of nutrition? especially when it plainly appears, that by reason of the defect or depra­vation of this nervous Juyce, nutrition is always frustrated or perverted.

Therefore it may be lawful, in the difficult Controversie concerning the Matter and Method of Cure, to propose this our Hypothesis, though it be a Paradox and very abstruse; to wit, that the nervous Juyce (which we have said was like the male seed) is poured out with the nutritious humor copiously suggested from the Arteries, as it were the genitive or seed of another Sex, every where upon all the parts; and that this former, being indued with active Elements, imbues the more thick matter, as with a certain Ferment, and impregnates it with animal Spirit; and when it so makes it, with a mutual entring in or coming together, to be dissolved and to go into parts, its particles being extricated one from the other (the Spirit infused help­ing) they are put upon bodies of the same measure with themselves, and are assimilated into their substances. In the mean time, because the animal Spirits are poured out in great plenty with the nervous Juyce, those which are at leisure from the work of nutrition, or remain after that is finished, turn aside every where into the Fibres, as into proper dwelling houses, and there being ready for the offices of sense and motion, stay; which offices indeed, that those Spirits the Inhabitants of the Fibres, may the better perform, they acquire from the blood watering the Mus­cles, certain auxiliary forces, wherefore they being endued with a certain elastick force, are apt to be highly rarified and as it were exploded.

But indeed we suppose, that as the nervous Liquor, being turgid with animal Spi­rit, causes the arterious humor to become nutritious; so in compensation of this the animal Spirits remaining of the work of nutrition, and every where disposed within the Fibres, receive from the arterious blood a mixture or certain Copula; by whose help and cooperation the same Spirits exert or put forth much more strongly their locomotive force. For it seems that little sulphureous bodies are added to the spiri­tuous-saline particles from the watering blood; and so when the animal Spirits are furnished with this Copula, they being stirred up into motion, shake off the borrowed particles, which being struck with a certain force, like the explosion of Gun-powder, suddenly intumifie the Muscles, and so by contracting them very much, they cause a vehement motive endeavour. We shall have an occasion of discoursing more at large of this, when we treat of the Motion of the Muscles.

Yet in the mean time, we shall take notice, that the Muscles of the whole Body, as to their motion, have a certain Analogy with the motion of the Heart. For indeed the animal Spirits in the Heart, flowing within the fibres and nervous threads, (with which this part is much beset) receive plentifully sulphureous little bodies from the inflowing blood distending the sides of either bosom, which whilst the same Spirits, being filled to a fulness, shake off and as it were explode, a Systole of the whole Heart (its sides being carried with a certain force inwards) is brought in or caused, where­by the blood, from either side the bosom, is cast out as it were by the impulse of a Spring or Bolt. Truly, unless the Spirits inhabiting the Heart, should receive food and matter of explosion from the blood it self, their stock, supplied or sent by the pas­sage of the few and small Nerves, would not suffice for the performing of the undis­continued motion. A sign of this is, that from a defect or depravation of the blood, [Page 136]as well as of the animal Spirits, the motion also of the Heart is defective or diminish­ed. And not much unlike in the Muscles, as in the Heart, is the business performed; the Spirits inhabiting their Fibres, receive a sulphureous Copula and apt for explo­sion, from the blood there more plentifully flowing than about the Membranes, with which being endued, as often as they receive from the Nerve as it were the fiery in­kindling or the match, the instinct of the motion to be performed, they being ex­cited, and striking of their Copula, very much inflate or blow up the Muscle, and intumifie it for performing or compassing the motive endeavour. Nor is it much to purpose, or makes any great difference, that the motion of the Heart, stirred up by a perpetual instinct, is found always necessary; but the Muscles the most of them only occasionally and at the command of the Animal, do put forth their motive power; for the Diaphragma and some Muscles, dedicated to Respiration, are urged with a perpetual Systole and Diastole, as well as the Heart it self.

From the aforesaid Hypothesis concerning the offices and uses of the nervous and arterious Juyce, Arguments that otherwise determine the work of Nutrition, may be easily answered. For that the blood is said rather to prey upon the solid parts than to replenish them, that ought to be attributed to the Disease and Dyscrasie of it, and not to it simply: because sometimes the blood is accused, for that it too much stuffs the solid parts; to wit, forasmuch as its mass being waterish and weak, it lays aside the alible Juyce (which not being truly cook'd, is still crude and vicious) with very great plenty about the habit of the Body, and so induces an Anasarca. In the mean time it ought to be granted, That as it is the blood that is evil which heaps up too much vicious nutriment; so it is the same, which being well and right, doth lauda­bly perform the office of Nutrition.

But that it is argued, That the nervous is rather the nourishing Juyce, because by reason of its defect, depravation or too prodigal expence, the acts of nutrition are wont to be hindred or perverted; it is easie to reply to this, That the impediments of the nervous Juyce, being made vicious, respect the form of nourishment, and not the matter of it: to wit, it sometimes happens, that the blood dispenses the alible matter in due plenty and disposition; which notwithstanding, by the fault of the nervous Juyce, is not rightly assimilated. When an impotency of motion comes upon a too great distension of the Muscle or Tendon with pain, shortly nutrition being hindred, a Jelly grows about the distempered part: which notwithstanding drops not out of the Nerve (as is commonly said) but the glutinous humor being poured out of the Arteries for aliment, for that it cannot be received by the hurt part, is gathered together there: nor is it to be thought, that Tumors, or Strumous Ulcers or the running Sores of the Evil do contain or pour out only a nervous humor, since the matter of either is for the most part bloody, which by reason of the evil Ferment of the nervous Juyce, puts on a strange form, and that diversly degenerous.

This supposition of the twofold Humor, for the matter and form of nourishment, is taken to be of egregious use for the solving of the most difficult Phaenomena, which are met with about the Distempers of the Brain and nervous Juyce: yea, that Patho­logy, seriously considered, seems to infer as a certain necessary consequence, that a twofold Juyce is necessary for the work of Nutrition; as some other time perhaps we may shew. In the mean time, leaving this Speculation, we shall proceed to the remaining Task of our Anatomy, to wit, the Neurologie or of the Nerves in particular.

CHAP. XXI.

THE division or distinction of the Nerves, by reason of their various respects, is wont to be manifold: to wit, as they are either soft or hard, singular or numerous in their beginnings; or that they serve either to the faculty of Sense, or Motion, or to both together. But they are commonly distinguished, That some Nerves arising within the Skull, proceed from the oblong Marrow; and others going out of the joynts of the Vertebrae, are derived from the spinal Marrow. But besides these, another man­ner of differencing them seems best to us; to wit, That some Nerves, as it were Clients and Servants of the Brain, perform only spontaneous Acts, and others, Mi­nisters and Servants of the Cerebel, are imployed only about the exercises of the in­voluntary Function. There will be no need to assign different Essences or Constitu­tions of Nerves according to these several differences: but rather that there be in­stituted a particular Cense or Muster of them, and following the order of Nature, that we especially unfold every one of them in the series in which they are disposed in the animal Body.

Among the Nerves arising from the Skull, the smelling Nerves, or those which are commonly called the Mammillary Processes, lead the way; for that they have their rise before all the rest, and are stretched out forward beyond the Brain it self. These Nerves go out of the shanks of the oblong Marrow within the chamfered bodies and chambers of the Optick Nerves; and being endued with a manifest cavity, open into the first Ventricle of the Brain on either side behind the same chamfered bodies; so that the humidity flowing between the folding of the Brain, is carried through these chanels into the mammillary Processes; whether they go farther forward, shall be anon inquired into: Because these Nerves being broad and large, arising near the chamfered bodies, and from thence stretched forward under the Basis of the Brain, their bulk is increased by degrees till they go into the round Processes like Paps, by which either bosom of the Cribrous or Sieve-like Bone is besmeared. Within the Socket of this Bone these Nerves, as yet soft and tender, obtain Coats of the Dura Mater; with which being divided into many fibres and filaments, and passing through the holes of the Sieve-like Bone, they go out of the Skull: from whence being di­lated or carried forward into the caverns of the Nostrils, and distributed on every side, they are inserted into the Membrane bespreading those Labyrinths.

If we inquire into the nature and use of these parts, without doubt the mammillary [Page 138]Processes and their medullar roots, with the fibres and small threads hanging to the same, are truly Nerves, and serve properly for the very Organ of the Smell. Seeing these conduce to the sense only without any local motion, therefore (even as the other hearing Nerve) whilst they are within the Skull, they are plainly medullar and soft; whereby the animal Spirits more easily moved within the more tender sub­stance of the Nerves, might convey more readily and accurately to the common Sen­sory the Ideas or forms of the sensible Species: But because the effluvia's or odorous breaths to be received by the naked Organ, carry oftentimes with them sharp and pricking Particles hurtful to the Brain and Nerves; therefore in the first course these Nerves being about to go out of the Skull, borrow Coats from the Dura Mater, which serve for Armour. Further, as these breaths (lest they should strike more sharply by rushing impetuously on the Sensory) being admitted only by little and little, and by small bands, ought to be brought through divers narrow turnings and windings of the Nostrils; therefore that these Nerves may the better receive the effluvia's flow­ing within the several dens, they are so divided into very many fibres and small threads or filaments, that there may be no passage of the Nostrils to which at least some of them are not destinated. And after this manner, although the exhalations, as it were torn into little Clouds, are received by the nervous filaments, and so care is sufficient­ly taken, that they being more thickly elevated, may not overwhelm or obscure the Sensory; yet lest any thing sharp and troublesom should be carried with them to the Brain, the cribrous bone is set before the doors as an obstacle, through whose little holes being strained, they may put off all sharpness. And lastly, they being carried through the softer Nerve, as it were another Medium, and so broken again, they at length being soft and gentle enough, are staid at the first Sensory.

But that these Nerves are noted through the whole with an open hollowness within the Skull, the reason seems to be, that the watry humor stilling out of the foldings of the Brain, and being derived into those chanels, might beat back and temper the impressions of the odours, when too sharp and fiery: for as the humors included in the Eye, variously refract the visible Species, whereby it passing at last through the Optick Nerve without any force, slides pleasantly to the common Sensory; so it is not improbable, that the water contained within these passages of the Nerve [...], does in like manner sweeten the species of the odours, and prepare them in some [...]easure for the Sensory. Wherefore it is observed, that Cattle and Beasts which are [...]d with herbage, have the mammillary Processes exceeding large and always full of water; to wit, lest the odours of the herbs continually attracted by them (unless their force should be blunted after the aforesaid manner) might hurt or overthrow their more weak brain. Besides, it is very likely that this watry juyce falling down from the infolding of the Brain, doth not only flow into the open chanels of the Nerves and the mammillary Processes, but also doth pass through by the passage of the fibres and filaments the holes of the Sieve-like Bone, and doth wet and continually moisten the cavities of the Nostrils, apt to be dryed or torrified too much by the Air thither at­tracted, and by the breath continually blown out. For it clearly appears, as we have elsewhere shewn, that the serous humors creep through the blind passages of the Nerves and Fibres, and by them wander from place to place. Yea it may be thought, that not only water, sufficient for the watering the Nostrils, doth by this way sweat through; but also whensoever the serous heap is gathered together in the Ventricles of the Brain, its superfluities or the excrementitious humor doth very often pass through the cribrous Bone by the passage of the Fibres, and is sent out. But we have in another place discoursed more largely of this.

The smelling Nerves, which have within the Skull their mammillary Processes de­pending on them, are much greater in an Ox, Goat, and in Cattle, and such like beasts that live on herbage, than in flesh-eating Animals; to wit, because in those there seems to be more need of the sense of smelling to be more exquisite for the know­ing the virtues of the manifold herbs. Also these Nerves are larger in all Brutes than in Man: the reason of which is, because they discern things only by the sense, and espe­cially their food by the smell; but Man learns many things by education or nurture and discourse, and is rather led by the taste and sight, than by the smell in chusing his aliments. These Nerves in Birds, as also in Fishes, are conspicuous enough; for either of these, even as four-footed beasts, seek out and chuse their food by the help or knowledge of the smell.

As to the Fibres and Filaments or little strings stretching out from the more soft [Page 139]Nerves through the holes of the Sieve-like Bone into the caverns of the Nose, these are found in all Creatures who have the mammillary Processes: so that it is not to be doubted, but that these Processes, with this Appendix and its medullary origine, is the Organ of the Smell. And what more confirms this thing, these filaments or little strings are far more, and more remarkable in hunting Hounds than in any other Ani­mal whatsoever. But besides these Nervulets drawn through the holes of the Sieve­like Bone into the Nostrils, two branches also are sent hither from the fifth pair, and distributed into both the Nostrils. The reason of this seems to be, because though the Nerves but now described, or of the first Conjugation, are properly smelling Nerves, and effect by themselves the sense of Smelling; yet these are assisted or joyned with other Nerves, also by those sent from the fifth pair, because the Organ of the Smell ought to have a consent with all other parts, which those subsidiary Nerves, by rea­son of the manifold branching out of the fifth pair, are wont to perform. It chiefly appears, that there is a certain nearness or strict affinity between the taste and the smell: and the cause of this consists, in that out of the same Trunk of the fifth pair certain Nerves are sent to the Palate, and others to the Nostrils. Concerning the reason of that wonderful consent which the Nostrils have with the Praecordia in sneez­ing, also wherefore that light titillation stirs up a Cough, shall be spoken of here­after, when we come to unfold the fifth pair and the intercostal Nerves. But in the mean time we shall take notice, that although many Nerves belong to the Organ of Smelling, yet that sense is properly performed by the Fibres interwoven in the in­ward Coat of the Nostrils: for those Fibres being struck by the sensible object, move and contract themselves variously according to the Idea of the impression; which Affection of them being carried by the passage of the Nerves to the Head, forasmuch as it is there staid by the common Sensory, causes the perception of the sense. Those sensible Fibres are diversly figured in several Animals; which is the reason, why odorous things do not alike affect all Animals. For what things by a mans nostrils, as endured with too sharp and pricking Effluvia's, are esteemed highly naught and stink­ing, as especially are dung and putrid flesh; the same are to Dogs, whose Organ of Smelling is made or consists of more robust or strong Fibres, and proportionate to those Effluvia's, as very grateful and chosen for food.

The second Conjugation are the Optick or seeing Nerves: concerning which we have shewn already, in the Anatomy of the Brain, after what manner they arise from behind the chamsered bodies out of the second section of the medullar shanks (which Galen calls the Chamber of the Optick Nerve) and descending from thence with a cer­tain compass are united, and being again separated and carried into the Ball of the Eyes, constitute with diffused Fibres the hard Coat. Moreover, in those Observa­tions we did but now take notice, that the Trunk of this Nerve growing a little hard without the Skull, was as it were a little bundle of very many Fibres or small strings growing together into one, and of produced Parallels, as it should seem for that end, that the animal Spirits, flowing in the whole Nerve, might be moved in so many lines or direct rays; to wit, whereby they may carry the visible Species, suffi­ciently refracted in the Eye, thence to the common Senfory by a direct beam, and not intorted or rolled about.

As often as in the distempers of the Eyes blackish pricks or concatenated pieces of any thing seem to be rolled before the Eyes, it is likely that this apparition is so made, because certain filaments or small strings of the Optick Nerve are shut up, which when the light cannot pass through rightly, as through the rest, so many as it were shadowy spaces appear in the middle of the clearness. These Nerves, because they only serve for the sense, are therefore more soft within the Skull: but because there may be need perhaps, that the Trunk of this Nerve ought to be sometimes dilated or spread abroad, sometimes bound close together or contracted according to the divers appearance and incourse of the objects; therefore very many Fibres, being sent out from the motory or moving Nerves of the Eyes, do every where compass and bind it about, and entring with it into the Ball of the Eye, are inserted partly near the root of the Optick Nerve, and partly penetrate more deeply the Sclerotick or hard Coat it self.

Further, the Optick Nerves are not only bound or environed with nervous Fibres sent from the third pair, but (as we have shewn above) with sanguiferous Vessels in their whole process. The office of which certainly is, both that there might be every where about the greater Trunk of this Nerve as it were a continual heat or sufficient [Page 140]fire-place; also perhaps, that the food of the bloody humor might be supplied to the Spirits, living there within the trunks of the nerves, far from the fountain, as is wont to be in other places.

Concerning the Fabrick of the Eye it self, and manner of seeing, also concerning the whole dioptrick provision, here seems a fit opportunity of discoursing: but this were to digress too far from our purpose, to wit, the mere or naked Doctrine of the Nerves; and I may the better pass by this addition, because this Province hath been sufficiently and accurately adorned by others. In the mean time we shall take notice, that as in the smelling, so also in seeing, the sense is performed, not so much by the help of the nerve, as of the fibres, which are interwoven with the organ: to wit, the little fibres in the Membranes of the Eyes, and especially those inserted into the Sclerotick Coat, and disposed after the manner of a net, do receive the impres­sion of the visible Species, and by representing the image of the thing, so as it is of­fered without, causes sight. But it is the office of the nerve it self to transmit in­wardly, as it were by the passage of the Optick Pipe, that image or sensible Species, and to carry it to the common Sensory.

The third Conjugation of Nerves are the moving nerves of the Eyes, which arise in the Basis of the medullar Stem behind the Tunnel; from whence going forwards nigh the pair of seeing nerves, and going out of the Skull with the other nerves destinated to the Eye, they are carried towards the Globe of the Eye; where, being presently divided into many branches, they provide it with moving Muscles; but with various difference in divers living Creatures. For in an Ox, who hath got a larger eye, the moving nerve of the eye imparts a branch to every one of the six common Muscles; and besides, from the nerves of the fourth, fifth, and sixth pair certain branches are distributed to some of the same Muscles: so that, as often as any Animal intends or applies the sense for the perceiving of this or that object, these nerves turn about the Eye, and compose it at their pleasure for the spontaneous beholding of the same. Be­sides we take notice, that the Eyes do get a diverse kind of involuntary motion; be­cause in Fear, Shame, Anger, Sadness, yea and in all Affections of the Head and Heart, whether we will or no, the Eyes are respectively figured. Wherefore 'tis highly probable, that these kind of pathetick motions of the Eyes, whereof the li­ving Creature is scarce knowing, are performed by the help of the other nerves, to wit, of those coming from the fourth, fifth and sixth pair: and that more mani­festly appears, because the same nerves which lend their branches to the Eye, take their origines from the Cerebel, the office of which we have often shewn to be, to dispense the Spirits for the exercise of the involuntary Function.

But concerning these Nerves of the third pair, which are properly called the Moving nerves of the Eyes, we observe, that in Man, a Dog, and in some other living Crea­tures they are found to be somewhat otherwise than in an Ox: for either nerve in these, as in the rest, is carried out of the Skull, divided into four branches, three of which are carried from thence into three straight distinct Muscles, to wit, one lifting up, the other bringing together, the third pressing close the Eye; the other branch of it goes forwards further with a single trunk, and is implanted in the middle of the Muscle going about the Eye, turning obliquely to the inward corner down­wards. From these it appears, that these Muscles, to which this nerve belongs in all, are sufficient almost of themselves to perform most spontaneous motions of the Eye: but where the aforesaid nerve is divided into four shoots, it constitutes a small and round infolding, out of which many small shoots creep through, and variously com­pass about the trunk of the Optick nerve; for what use it is so made, we have al­ready intimated.

The fourth Conjugation of Nerves (which we call rightly the Fourth by order and succession, although it is accounted the eighth and last by Fallopius) hath a diverse ori­gine from all the rest. For whereas most of the others proceed from the foot or sides of the oblong Marrow, this hath its root in the top of it behind the round Protube­rances, called Nates and Testes: From whenc, bending more forward nigh the sides of the oblong Marrow, it is presently hid under the Dura Mater; under which go­ing along for some space, and passing through the Skull at the same hole with the rest destinated to the Eye, it is bestowed with a single trunk, not communicating with any of the other nerves, wholly on the Muscle called the Trochlear Muscle. Above we called these nerves the Patheiick nerves of the Eyes: for although some besides may deserve this name, (as shall be shewn by and by) yet 'tis most likely, that the [Page 141]proper office of these is to move the Eyes pathetically, according to the force of the Passions and instinct of Nature, delivered and remanded from the Brain to the Cere­bel, and so on the contrary, from this to that through the Nates and Testes, and their medullar Processes. For, as we have shewn, that by the diverse impulse and waving of the animal Spirits dwelling in this by-path, there are instituted certain mutual commerces between the Brain and the Praecordia, (the Cerebel mediating between either) it will be of necessity, that these nerves, rooted in the middle way, should be struck by every tending downwards or remove of the Spirits, going this way or that way, and so the motions of the Eyes to follow the affections of those parts. All perfect Animals are furnished with these nerves; and in truth, as none of them but are obnoxious to Anger, Love, Hatred, and other Affections, so every little Crea­ture shew these by the mere aspect and by the gesture it self of the Eyes. We see sometimes the greater Pike gaping for his prey first of all to roll about his eyes, and to look sour; then with a swist shooting out of his body to invade the lesser fry of fish.

CHAP. XXII.

OF the aforesaid four Pair of Nerves, the two former seem chiefly to serve for the Sense only, but the two latter for Motion; and every single nerve of them destinated to a peculiar Province: but this which follows next, to wit, the fifth Conjugation of Nerves serves for the exercise of either Faculty, to wit, both of Sense and Motion; nor is its Province so strictly bounded, that it should belong only to one member, for it is distributed to the Eyes, Nose, and Palate, and the rest of the parts of the Face; and besides, helps in its part in some sort the offices and actions of the Praecordia and almost of all the Viscera.

This pair (which by the Ancients was accounted the third, by us the fifth pair, and that by right of order or position) below the former nerves, proceeds with a broad and large trunk from the sides of the annular Protuberance or Process sent out from the Cerebel. It consists of very many Fibres gathered together, some of which are soft, others hard; so that the great trunk of it near its beginning, is nothing else than a little bundle of very many nerves, some of which are bestowed on these parts, and others on other parts, and in some they perform the offices of motion, in others of sense. But that so many nerves being destinated to so many several members, and remote one from another, yet arising together, are collected as it were into one bundle, the reason is, that in all the parts to which those nerves be­long, a certain Sympathy and consent of actions might be conserved: to wit, the communion of those nerves is the cause why the sight and smell move spittle and please the Palate; nor by any other means are the Praecordia affected, according to the various conceptions of the Brain, and transmit their affections o he several parts of the Face; from whence the aspect or countenance of the whole Animal is pathe­tically figured, as shall be shewed more particularly below.

In the mean time, let us deliver a short Hypotype or figure of this Nerve; its trunk going out of the sides of the greater Ring, sometimes near its beginning, but oftner the Dura Mater being first perforated or passed through, is divided into two noted branches. The first of these tending straight downward, going out of the Skull at a proper hole, in its descent towards the lower Jaw, (to whose parts it is chiefly destinated) is divided into more branches, with which it furnishes the Tem­ple-muscle, also the Muscles of the Face and Cheeks. Moreover from them shoots and branches are distributed into the Lips, Gums, roots of the Teeth, Jaws, Throat, the farther end of the Palate, yea and the Tongue; for this reason chiefly, that the nerves going out of the lower branch of the fifth pair, might effect, besides sense, the divers offices of Taste and Touch or Feeling, and motions of a various kind in the aforesaid members and parts; most of which, as the chewing of the aliment, also those which have respect to configuration or framing of the mouth and face in laugh­ing or weeping (as we have already noted) are performed unknown to the Brain, that is involuntarily, and by the help of the Cerebel only, from which these Nerves are derived.

The other superior, and also the greater branch of the fifth pair under the Dura Mater nigh the side of the Turkey Chair goes straight forward for a little space, and is inlarged into some shoots over against the pituitary Glandula to the trunk of the Ca­rotick Artery or the wonderful Net, (where it is present) then it is inoculated into the nerve of the sixth pair, and from thence sends back sometimes one, sometimes two shoots; which being united with another shoot, turned back from the nerve of the sixth pair, constitute the root or first trunk of the intercostal Nerve. Concerning this intercostal nerve, which is made of the lower ramification or branching out of the nerves of the fifth and sixth pair, it shall be spoken of particularly hereafter.

Presently after the branches or shoots reflected or bent back for the root of the in­tercostal nerve, that greater nerve of the fifth pair is divided into two noted branches. The lesser and uppermost of these tending towards the globe of the Eye, and becom­ing again twofold, sends forth two branches from it self; one of which turning to­wards the inward side of the Bone, containing the ball or angle of the Eye, is divided into two shoots. The other of these having passed through the Bone nigh the mam­millary Processes, is carried into the nostrils: the office of this nerve is to keep a Sympathy and consent of action between the nostrils and some other parts: but the other branch of this division is bestowed on the Muscle by which Brutes wink.

The second Ophthalmick branch of the fifth pair is divided into four or five shoots, all which going forward above the Muscles of the Eye, and in some part passing through its Glandula's, are almost all lost in the Eye-brows, unless that in the passage they send down two small shoots which enter the Sclerotick Coat a little below the Tendons of the Mulcles, and reach to the Ʋvea, or the fourth thin Membrane that cloaths the Optick nerve; yea and also send in the passage small shoots to the Glan­dula's of the Eye. It seems that these nerves of the fifth pair, being distributed into the Glandula's of the Eyes and Eye-brows, serve chiefly to the involuntary and pa­thetick actions of those parts; the chief of which are, the languishing and mournful aspect of the Eyes in weeping, and the unwilling pouring out of tears. For as the lower branching of the fifth pair, to wit, the intercostal nerve, provideth in man for the Praecordia, it easily happens, that from the fad affection of these, the Cardiack branches of this nerve being forced and wrinkled into Convulsions, the aforesaid Oph­thalmick branches also so correspond, and by wrinkling the Eye-brows, and by com­pressing the Glandula's, produce those kind of looks of the Eyes, and marks of sorrow and grief. Further it is observed, that from the Ophthalmick branch of the fifth pair a certain shoot is sent back higher nigh the heads of the Musoles; which when it has passed through at a proper hole, the Bone containing the ball of the Eye, is car­ried straight into the caverns of the Nostrils. Hence, as I think, a reason may be given, wherefore passing out of a dark place into the light, at the first beholding of the Sun, presently whether we will or no we shall sneez; to wit, the eyes being too strongly struck by the object, and being suddenly and disorderly moved, that they might turn themselves aside, the same affection is immediately communicated through the aforesaid Nerve to the Membrane covering the hollow caverns of the Nostrils, which being thence contracted and wrinkled, (as it is wont by some sharp thing pulling it) provokes sneezing.

The second or greater branch of the second division of the Nerve of the fifth pair being carried nigh the ball of the Eye, is again divided into two branches. The lower of these being bent downwards, cleaving into many shoots, is bestowed on the Palate and upper region of the Jaws: The other and higher branch of this second division stretch­ing beyond the ball of the Eye, passes through, together with the Vein and Artery, a proper hole made in the bone of the upper Jaw; which Vessels this Nerve climbs and variously compasses about with many shoots sent forth; then arising out of the bone, it imparts little branches to the Muscles of the Cheeks, Lips, Nose, and to the roots of the upper Teeth. Therefore forasmuch as this Nerve embraces and binds about the sanguiferous Vessels destinated to the Cheeks and the other parts of the Face; from hence a reason may be given, why the face is covered with blushing by shame: for the animal Spirits being disturbed by the imagination of an unseemly thing, by and by endeavouring as it were to hide the face, their irregularities enter this Nerve, so that the shoots of the same Nerve embracing the blood carrying Ves­sels, by compressing and pulling the same, cause the blood to be more forced into the Cheeks and Face, and the Veins being bound hard to be there for some time staid and detained. But forasmuch as many shoots and fibres of the same maxillar Nerve, derived [Page 143]from the fifth pair, interweave themselves with the flesh and skin of the Lips, hence the reason is plain, why these parts are so very sensible, and besides, why the mutual kisses of Lovers, impressed on the Lips, so easily irritate love and lust by affecting both the Praecordia and Genitals; to wit, because the lower branching of the same fifth pair actuates these parts constituted in the middle and lower Belly, and draws them into the like affection with the Lips. The same reason holds of Love presently admitted by the eyes, that as the Poet says,

We have but now intimated, that many shoots of this Nerve were destinated for the business of chewing; and therefore, because the aliments to be taken ought to undergo not only the examination of the taste, but also of the smell and sight, from the same Nerve, whose branches being sent to the Palate and Jaws, perform the business of chewing, other shoots, as it were fore-runners, are carried to the Nostrils and Eyes, to wit, that these Organs of the other Senses might be furnished with some helps of probation also, for the better knowing or distinguishing the objects of taste. Certainly from the nearness of kindred and manifold affinity of this Nerve, being also much dif­fused in the Head, the mutual dependencies and confederations of very many of its parts, proceed. But how this Nerve in other Provinces, to wit, in the Thorax and lower belly, and there about the motions and sensions of the Praecordia and Viscera, doth cause various Sympathies of them among themselves and with other parts, shall afterwards be more largely shewn, when we shall speak particularly of the intercostal Nerve, which is rooted in this nerve of the fifth pair; where, from the manifold communication of this nerve, may be easily drawn the reasons of sneezing, yawning, laughing, crying, and of other actions merely natural. In the mean time, the su­perior branching of the nerve of the fifth pair shews it self after this manner in the Head, and almost after the same manner is divaricated in most living Creatures; ex­cept however, that in some, presently after its rise, it is divided into t [...]ree great branches; one of which is destinated to the lower Jaw, the other to the Eye and Nose, and the third to the Cheek.

The Nerve of the sixth Conjugation follows, which arising out of the lowest foot of the annular Protuberance, and being hid under the Dura Mater, presently goes out of the Skull at the same hole with the nerves of the third and fourth pair, and is carried with a single trunk into the ball of the Eye; but so, that near the side of the Turkey Chair it is inoculated with the second branch, or the greater of the fifth pair; from whence it turns back, sometimes one little branch, sometimes two; which be­ing united with the branches of the fifth pair running back, constitute the beginning of the intercostal nerve. Then this nerve going forwards, is divided into two bran­ches near the ball of the Eye; one of which is inserted into the Muscle drawing back the Eye planted in its outward angle; and the other being torn into various fibres, is bestowed on the seventh Muscle proper to Brutes; so that this nerve also seems to serve to those motions of the Eye that are almost only pathetick, or excited by natural Instinct. For, as to the use of the former shoot, it plainly appears, that it is innate to every Animal in a sudden fear to draw the eyes backward, and to look for what is to be feared on either side and behind: then as to its other shoot, whereby Brutes wink or twinkle the eye, it is obvious that this same motion is sudden and extemporary, with­out any previous intention, whereby the eye endeavours to shun the injuries of outward things that occur.

The seventh Conjugation of Nerves, accounted for the fifth by the Ancients, is imployed about the sense of hearing. Of this pair commonly are noted two Processes, the one soft, the other hard; which indeed seem to be two distinct nerves, for that although they have their beginnings nigh one another, yet are somewhat distinct, and are carried to divers Organs; in the mean time, either agreeing in a certain common respect of use or action. For whilst one nerve perform the act of hearing, the other supplies some requisites whereby that act may be the better performed: wherefore we shall not much strive against the common description of this pair, by which it is taken for one. The process of this pair, or the auditory nerve properly, which is called the soft Branch, seems to arise in man out of the lower side of the ringy Protuberance, and in beasts out of the midst of the lesser Ring. In some Dis­sections I plainly sound, that this softer nerve, having its beginning lower, seemed [Page 144]to ascend a little before it went out of the medullar stock; and the other more hard nerve seeming to arise higher (viz. out of the medullar whitish line leading about the bottom of the fourth Ventricle) did descend a little, and arose near the meeting with the other. This softer nerve is carried into the passage of the stony Bone, where entring into the den destinated for the receiving the found, which is on this side the Snail-like winding and the Drum, it so infolds it self into the most thin Membrane wherewith that den is covered, that as often as the Air implanted in that cavern is moved by the stroke of the external Air made upon the Drum, this impression striking this Membrane, and stirring up as it were an undulation of the animal Spirits, is forth­with carried towards the common Sensory by the passage of the nerve there implant­ed. There will be a more opportune place of discoursing, after what manner, and by what sort of Organs Hearing is performed, when we shall speak of the Senses.

The other Nerve of this pair, or the more hard process, which conduces rather to motion than sense, passing through the stony Bone at an hole proper to it self, arises near the auditory passage, where it presently receives into its trunk a branch from the wandring pair brought thither; then immediately after that joyning together or coalition, it is divided into two branches: The first of these tending downwards, is bestowed upon the Muscles of the Tongue and the Bone Hyoides; the other going about the auditory passage, and bending more upwards, is divided into three shoots; the first of which, answering to the nerve of the former division, bestows some shoots on the Muscles of the Lips, Mouth, Face, and Nostrils, and so actuates some exte­rior Organs for the forming the voice, as the former doth some interior Organs. The second shoot of this division distributes its shoots into the Muscles of the Eye­brows and Forehead; and the third into the Muscles of the Ear it self. The offices and uses of all these have been already shewn, the summ of which is, that as often as the sound is admitted in, especially if it be any ways unusual, new, or to be won­dred at, presently by a certain natural instinct the Ears and Eyes erect and open themselves: to wit, for that end shoots from this nerve are inserted into the Mus­cles of the Eye-lids and Ears, that by the passage of these, the Spirits inhabiting ei­ther Region, might be called out as it were to watch. For a like reason shoots from the same hard process of this nerve are distributed both into the Muscles of the Tongue and of the Bone Hyoides; as also into those of the Lips and the outward parts of the Mouth, that by their passage, the sound being transmitted further to these Organs of the voice, it being equal or like the same, might officiously answer it as were an Echo. That the descriptions of the aforesaid nerves might be better under­stood, I have thought good here to represent in the following Figure the branchings of the fifth and sixth pair. The seventh pair is fitly delineated in the ninth Figure.

CHAP. XXIII.

THE Conjugation of the Nerves of the eighth pair, accounted by the An­cients for the sixth, is called the Wandring pair; to wit, for that its Nerve, not content with one member or region of the Body, is thought to respect divers parts, and those different, and situate at a great distance one from another, and to reach forth its branchings, not only in the neighbourhood about the Head and Neck, but through the whole cavity of the middle and lowest Belly, and to most of the Bowels in either. But indeed this nerve hath a province large enough, yet not so diffuse as is commonly thought: for many other nerves, inoculated into this, joyn themselves with it, and are accounted a part of it, although they have distinct be­ginnings, and going away again from the nerve of the eighth pair, have peculiar diva­rications, and different from it. Wherefore, that we may give to each its own, we shall endeavour to prosecute this nerve of the wandring pair from the beginning to the end; and also shew the confederations and coincidences or joynings together of others with it.

The eighth Conjugation therefore of the Nerves arises below the auditory or hear­ing nerves out of the sides of the oblong Marrow, its root consisting of numerous Fi­bres. In a man there are at least twelve, some of which are greater, others smal­ler, to which is added a noted Fibre, or rather Nerve, much greater than the rest, from the spinal Marrow, which being joyned with them, and wrapped about with the same Coat, taken from the Dura Mater, goes forth together out of the Skull, as if they all grew into one Trunk: but that accessory nerve, yea and many other Fibres, do still remain distinct under that covering, and afterwards departing asunder, are carried into peculiar provinces.

Because this spinal Nerve having passed the Skull, leaving its Conjugation, is carried to the muscles of the Neck and Shoulders; besides, the noted Fibre, out of the beginning of the wandring pair, is presently carried into the hard process of the se­venth Conjugation; and two other Fibres, having presently left the company of the rest, go into the muscles of the Throat and Neck: but the rest of the Fibres, being collected together, go forward still as Companions, and instead of their other Com­panions which departed from them, they presently get new in their places; to wit, sometimes the whole trunk of the intercostal nerve it self, as is seen in most four­footed Beasts, sometimes only a branch of it comes to them, as is observed in Man and some other living Creatures.

In this place where the trunk or branch of the intercostal Nerve is inoculated into the trunk of the wandring pair, a noted infolding is constituted, to wit, the trunk of the nerve being there made greater, seems to he listed up, and to grow out into a certain Tumor like to a callous or sinewy swelled body: here, for that it is somewhat long, it is called by Fallopius the Olive body; of which sort the same Author affirms, there comes to this nerve sometimes one, sometimes two; but in truth, one is con­stantly found in the trunk of the wandring pair, but the other in the neighbouring intercostal.

Of these sort of infoldings in general we shall take notice, that they are made in the Nerves, as joynts in a Cane, or knots in the stem of a Tree, viz. as often as a branch goes out of the trunk, or sliding into another place, is received into the same; and when oftentimes some shoots go away from the same place, and others come to it, the infolding there becomes greater; and so the more branches and shoots do happen to come together any where, or to go out of a nerve, the greater the bulk and magni­tude of the infolding is increased: but if at any time a branch seems to proceed from any nerve without constituting an infolding, in truth, being included only in the same Coat, it is not accounted so much a branch as a companion, which by a passage long before, had gone together forwards, as a single nerve it self, and distinct enough, nor was it at all inoculated before its departure. But the use of these same infoldings seems to be the same with the knots in the stem of a Tree, or such as the turnings aside or by-paths that lye near cross-ways; to wit, that when the animal Spirits, to­gether [Page 147]with the nervous Juyce, institute divers journies, lest mutually meeting, they should be confounded, they may be able to turn aside a little, and depart one from another till they may recover their orders and just method.

In the Dissection of the Nerves, which are distributed to the Praecordia and Viscera, the two Ganglioform infoldings, to wit, the aforesaid in the trunk of the wandring pair, and the other near growing in the intercostal nerve, are as it were two bound­ing stones, which being first diligently traced, the other threads of the Anatomical task, both on this and that side, are easily handled. But that these infoldings may be sound, the trunk of the Carotidick. Artery is laid open on both sides between the Mus­cles of the Neck; then by following its tract, the aforesaid Olive bodies come into view about the insertion of the lower Mandible; out of which, both the upper be­ginnings and the lower branchings of either nerve, may be designed or drawn. But because about this place the nerves begin to be figured otherwise in a Man than in Brutes; that the reason of the difference may be known, we will here prosecute apart and distinctly the Neurologie or Doctrine of the Nerves of either; and first we shall deliver the Hypothesis of the wandring pair, and its confederations with the intercostal and other nerves, as they are found in Man.

The Ganglioform infolding therefore being constituted upon the Trunk of the wandring pair, receives one Nerve sent into it elsewhere, and sends forth another from it self. To this is brought a shoot from the intercostal nerve different from most brute beasts, where the whole trunk of the intercostal nerve comes, and seems to be united to the wandring pair. But from the aforesaid infolding, a noted branch be­ing sent forth, is carried towards the Larynx, which when it is divided into three shoots, the first of them is stretched out into the Sphincter of the Throat; the second being hid under the Scutiform or Shield-like Cartilage, distributes its shoots to the upper Muscles of the Larynx, and to the Muscles by which the chink of the Larynx is shut up; and the third also entring the Shield-like Cartilage, meets the top of the returning nerve, and is united to the same. Such an inoculating of this nerve, with the returning nerve, is constantly found in man and in all other perfect Animals; the reason of which is delivered anon.

Below the aforesaid infolding of the wandring pair, its stem, near the side of the ascending Caroditick Artery, goes forward straight downwards, and in its journey imparts some small shoots to the same, which sometimes compass about the trunk of its Vessel, sometimes are inserted into its Coats. In the lower part of the Neck this trunk of the wandring pair admits a branch of the intercostal nerve from its neighbouring infolding, and in the left side about that place sends forth another nerve from it self into the returning nerve; which cross branch, being stretched out only in the lest side, is found in man and all brute beasts: but from thence the trunk of the wandring pair descends without any noted branchings till it comes over against the first or second Rib; where another infolding being made, many shoots and nu­merous fibres are sent forth towards the Heart and its Appendix. But this divari­cation of the Cardiack nerves is not after the same manner altogether in either side.

For in the left side one or two noted shoots being sent forth, together with other shoots arising from the intercostal Nerve, are inferted into the Cardiack infolding; but many fibres going out at the same place, are distributed to the Vessels hanging to the Heart, and to its little Ears and Pericardium. In the right side a noted shoot going into the greater Cardiack infolding, another into the less, and two other shoots from the middle infolding of the intercostal Trunk towards the Cardiack infolding, associate themselves and are united. Besides, numerous Fibres in like manner de­scend into the Vessels of the Heart and the Pericardium. Also the returning Nerve in this side arising higher, is turned back about the axillary Artery, when in the left side the same going away much lower than this infolding, from the Trunk of the wan­dring pair, compasses about the descending Trunk of the Aorta, and from thence it is turned back upwards.

The returning Nerve, although it seems a branch sent forth from the Trunk of the wandring pair, being indeed a distinct and singular nerve, comes even from the beginning of the wandring pair; yet for better conducts sake it is contained under the same Coat with the rest of the Trunk of the wandring pair. In either side about the knots of reflection or turning back, it sends forth shoots and fibres which are di­stributed into the Vessels of the Heart. The reflected Nerve in its ascent receives in the left side a branch from the middle infolding of the Intercostal, and another from [Page 148]the wandring pair; but either running back, distributes many shoots to the rough Artery; then its extremity meeting with the shoot, which is sent out of the Ganglio­form infolding of the wandring pair, is united to it.

A little below the coming away of the returning Nerve on the left side from the Trunk of the wandring pair, another noted branch is sent forth on both sides; which being carried towards the Heart, covering its Basis in the hinder Region, meets it on both sides, and disperses in all its process branches through the whole Superficies of the Heart. As shoots go from these branches into the hinder part of the Heart, so many branches and shoots go from the Cardiack infoldings which are divaricated into its fore-part.

But there are two Infoldings from which the Nerves are distributed into the Heart. The upper and greater is between the Aorta and the Pneumonick Artery. The nerves constituting this are one or two noted branches that descend hither from ei­ther side the Trunk of the wandring pair; but chiefly many nerves from either inter­costal nerve, to wit, from the midst of its infolding. From this infolding two or three noted nerves are carried under the Aorta into the left side of the Heart. But from this infolding, a shoot being sent forth, making as it were an handle, compasses about the pneumonick Artery; and a branch descending from the right Trunk of the wandring pair to the exterior part of this handle, and another, which being carried from the nerve which is destinated to the hinder region of the Heart, meet toge­ther and make the lesser infolding; from which nerves are sent into the right side of the fore-part of the Heart.

We are to take notice, That in brute Animals many more and far greater Nerves are carried from the Trunk of the wandring pair into the Heart and its Appendix than in Man, to wit, in whom the chief Cardiack nerves or belonging to the Heart proceed from the intercostal pair, as is shewed below; wherefore in Brutes, for that reason, the wandring pair affords greater supplies or subsidies to the Heart, because the intercostal nerve scarcely contributes any to it. Further, through the whole tract of the wandring pair, from whence the Cardiack nerves proceed, very many small shoots, being sent forth on both sides, are inserted into the Oesophagus and the Glandula's implanted without the Pericardium.

From the Region of the Heart, the Trunk of the wandring pair sends forth many noted shoots on both sides, which being carried into the Lungs, are distributed, to­gether with the blood-carrying Vessels, through their whole substance, and in their passage step by step they follow the Pipes of the Bronchia, both the Arteries and the Veins, and many shoots being sent forth on every side, the climb upon and compass about these Vessels; then the Trunk of the same wandring pair, descending on both sides, nigh the sides of the Trachea, distributes many shoots also into the Coats of the Oesophagus.

Below the Pneumonick branches, either Trunk of the wandring pair going for­wards downwards nigh the sides of the Oesophagus, is divided into two branches, viz. into the exterior or more outward, and the interior or more inward. Both the in­ward branches inclining towards one another mutually, do again grow into the same Nerve, which being sent straight down towards the Oesophagus, and being carried nigh the inward part of its Orifice, is bent back from thence, and creeps through its upper part. From both branches, being carried nigh the opposite parts of the supe­rior Orifice, many shoots are produced, which being mutually inoculated, do con­stitute the nervous infolding like a little net. The Stomachical lower branch sends forth very many fibres and shoots nigh the left part of the bottom of the Ventricle, which are united with others, sent forth from the Mesenterick and Splenetick infold­ing. Further, in the right part of the same bottom of the Ventricle, shoots being sent forth from either Stomachical branch, are united with other shoots sent upwards from the Hepatick infolding; and about this place either Trunk of the Nerves of the eighth pair seems to be terminated, for that the last that may be perceived of it are some shoots sent forth from the Stomachical branches, which are inoculated or in­grassed with the little branches or fibres sent upwards from the Mesenterick infold­ings.

CHAP. XXIV.

AFter this manner the beginning and branchings out of the Nerves of the eighth pair are disposed in Man: and they are almost after the same manner in Brutes, unless the Cardiack branches be more, because in these they go out only from this one Conjugation. The Figure or Type of all these is well designed or drawn in the ninth Table or Figure. It now remains, recollecting the Tracts of this Description, or at least the things chiefly to be noted, that we inquire into the Rea­sons of their Phaenomena or Appearances.

This Nerve, presently after its rise, appears with numerous Fibres, as may be dis­cerned in the ninth Figure E: the reason of which is, because many nerves here ari­sing together, and deriving plenty of animal Spirits from the same stock or provision, ought to carry the same to divers parts, and remote one from another; and there­fore they assume their Latex or Juyce, not at one Trunk, as the blood-carrying Ves­sels, and afterwards distribute it equally by branches and shoots here and there stretch­ed out; because the Spirits, derived from the same Fountain, have need to flow into these parts separate from them, and variously to transpose and change their influence: wherefore for this business it is required (that we may not suppose little doors in the middle of the branchings out of the nerves, as are in the Pipes of a musical Organ) that the nerves, which are destinated for the performing of divers offices respectively in distinct parts, should be single in their whole passage, and of themselves distinct chanels of Spirits; for the sake of a better conduct many of them are collected to­gether, and seem to grow together into one Trunk; but they are parted both in their beginning, and also in their whole journey, and distinguished, though involved in the same Coat, and so are carried to the respective parts. Otherwise how should it come to pass, that the Spirits to be carried for the performing the instinct of mo­tion towards the Stomach, do not enter at the same time the Lungs or Praecordia, and actuate them with an inordinate influence? For indeed the shoots of the nerves of the wandring pair may be followed by the eyes and hand backwards towards the beginning, from the parts into which they are inserted, and where they seem to be united into the same Trunk, so separated with the singer, that it may appear they are single. After the same manner we have plainly separated one from another the returning nerve also, and others, their common Coat being dissected. Yet in the mean time we deny not, that in their progress they do communicate one with ano­ther by Fibres meeting mutually, if it be granted, that the same, although they arise together, in their very rise it self are in a manner distinct. For by reason of the nearness of the beginning and progress, though all the nerves of the wandring pair have a certain Sympathy and consent in their actions; yet for that they consist of parted strings, they perform their actions successively, and convey the influences of the Spirits to these parts separate from those.

We have already shewn, that the Nerve of the wandring pair, and others belong­ing to its family, do serve almost only to the involuntary Function. Wherefore it may be thought, that as there are many shoots and fibres, which going out distinctly from the same origine, are carried to divers parts, that indeed those Bowels and Members, into which these nerves are inserted, do perform their particular actions, stirred up either by the instinct of Nature, or by the force of the Passions, the Ani­mal in the mean time scarce knowing it: yea also, that when certain other nerves, arising afar off, are joyned to this Trunk of the wandring pair, and communicate with it near the very origine of it; this seems to be therefore done, that those nerves, an affinity with the wandring pair being begun, may be drawn into Sympathy with it, and into an unity of action of the involuntary Function. This appears clearly by the accessory nerve from the Back bone, and some others, as shall be manifested anon.

In the mean time, we shall observe concerning the Fibres of the wandring pair, first that a noted shoot, inclining towards the vocal process of the seventh pair, is [Page 150]united with the same, as in the ninth Figure e. Hence a reason may be taken, where­fore in every violent Passion, as of Anger, Fear, Joy, and the like, without the will or intention of the Animal, the Tongue sends forth a voice, as an index of the excited affection; so that not only men, but some brute beasts, in their fleeing or re­joycing, wail, cry out, and make a noise.

Secondly, From the beginning of the wandring pair very many Fibres are distri­buted into the Muscles of the Neck, Figure the ninth FFF. in which there seems lit­tle need of the stirring up of spontaneous motions in that part; for to this task the Vertebral nerves serve sufficiently. Notwithstanding the aforesaid Fibres of the wan­dring pair are the cause why the Neck is moved about in fear, or at any noise or sus­picion of danger; and also, why in some Animals, from indignation or pride, the Mus­cles into which these nerves are inserted, being inflated very much, their necks swell up, and the Crests of many are erected, Of how great use the accessory nerve, coming from the Spine to the wandring pair, is for the pathetick motions of the Arms, shall be shewed presently.

Thirdly, The other Fibres of the wandring pair, being gathered together, seem to grow together into the same Trunk, which presently constitures the Ganglioform infolding from a shoot coming from the intercostal nerve, as in Figure the ninth G.H. And indeed it is very likely, that of these Fibres, which are complicated together in the Trunk of the wandring pair, one is destinated to the returning nerve, another to the Praecordia, a third to the Lungs, and lastly, another to the Ventricle; all which, although they have communication among themselves, and for the sake of a better conduct are gathered together in one, yet they are still distinct from their very original, and constitute divers passages of the animal Spirits.

But that a shoot is carried from the intercostal Nerve into the upper infolding of the wandring pair, as in the ninth Figure h; the reason is, that between these nerves a certain strict affinity and kindred might be, and that either of them might be affe­cted with the others offices. For as the nerve of the wandring pair distributes shoots chiefly to the Pracordia, and the Stomach, and the intercostal Nerve to the rest of the Viscera of the lower Belly; we may observe, that between all these there are not only some commerces, but Sympathies, and a consent of Actions and Passions; wherefore there is a necessity, that the nerves designed to either parts, should commu­nicate among themselves. Further, in Man the intercostal nerve imparts to the Heart and its Appendix more shoots and fibres than the nerve of the wandring pair: where fore these nerves do not only communicate by these superiour infoldings, but also again a little lower by a shoot sent out from the cervical infolding, or that of the Neck.

From the aforesaid infolding a noted branch of the wandring pair is sent forth into the Muscles of the Larynx, a certain branch of which, entring the Shield-like Car­tilage, meets with the returning nerve, and is united to it Fig. 9. h. It will not be diffi­cult to collect what the use of this nerve may be; for seeing the Larynx or the rough Artery serves both for the drawning in and putting out of the breath, and also for the modulating the voice; for either office that its Trunk, like the folds in a pair of Bellows, may become sometimes more short, sometimes more at length, these same ringy Cartilages ought to be pulled together, or contracted sometimes upward, and sometimes downward. That a flat voice or sound might be formed, they ought to be prest down as much as may be to the bottom; but if you would form a more shrill or sharp sound or voice, the superiour Rings are lifted up; to wit, that the sound might be broken but only in the very passage of the Jaws. For the performing of this double motion of the Larynx two nerves are constituted like the hands of a Piper, one of which stops the lower holes, the other the upper of the Pipe: to wit, the shoots and branches of the returning nerve being lifted up from below, move the ringy Cartilages downwards; and the nerve sent out from above from this infolding; presently draws the more superior upwards. Further, because a certain consent and joynt action is required in both nerves, therefore they are mutually inoculated or ingraffed: yea, whenas either of them returning, distributes frequent shoots into ei­ther side of the Trachea; it seems that those that are sent out into the right part, move its Rings downwards for inspiration and a strong Voice; and the others, going out on both sides into the left part, carry the Rings upward for Expiration and for an acute or sharp Voice. Moreover, as the instinct for the motion of depression or pressing down is delivered from the knots of the recourse or reflections; so the im­pression, [Page 151]for the elation or lifting up of those parts, is received from this nerve of the Ganglioform infolding.

A noted branch from the middle infolding of the intercostal Nerve is carried into the Trunk of the wandring pair, Fig. 9. i. For what end that is so, we have shewn already; to wit, that the commerces of the Spirits dwelling in both nerves, might be strengthened: but it should be noted, that it is only so in the left side where the Trunk of the wandring pair shews it self single for a long space; but in the right side, where the returning nerve goes from it much higher, here the other nerve from the intercostal infolding is plainly wanting.

About the Region of the first or second Rib, another noted infolding appears in the Trunk of the wandring pair, from which many shoots and fibres are sent towards the Heart and its Appendix, Fig. 9. k. Further, in brute Animals, about this place, the intercostal nerve leaves the Trunk of the wandring pair. Without doubt, some animal Spirits go apart in this infolding, which are destinated to the anterior region of the Heart, also to the Pericardium and some of its Vessels, whilst other Spirits pass through, which a little lower are derived into the hinder region of the Heart; and which being yet carried further, go to the Lungs, and lastly to the Ventricle.

We may observe, that from the aforesaid infolding of the wandring pair numerous shoots and fibres are sent forth, which are distributed into the little ears of the Heart and all the sanguiferous Vessels belonging to the Heart, Fig. 9. l. m. which fibres and nervous shoots creeping along like Ivy, thickly cover over the Coats of the Vessels, and enter them in very many places, and variously bind them about. Truly this copious distribution of the nerves doth effect the pulsisick force in the little ears of the Heart and in the Arteries, or at least seems to excite it; and so to erect and strengthen those parts by a continual influx of the animal Spirits through these nerves, that they may be able to sustain an undiscontinued reciprocation of Systole and Diastole. Moreover, that the thick fibres and shoots of the nerves are inserted both into the Veins and Arteries, and bind both those kind of Vessels, and variously compass them about, we may lawfully suppose, that these nerves, as it were Reins put upon these blood-carrying Vessels, do sometimes dilate, and sometimes bind them hard toge­ther for the determining the motion of the Blood according to the various force of the Passions, or to deduce it here and there after a manifold manner; for by this means it comes to pass, that in fear the excursion of the blood is hindred, and in other Affections its motion is respectively altered.

But that many shoots and branches are inserted into the Pericardium, it seems to be for this use; to wit, that that little Chest which is made like a Fort for the defend­ing the Heart from injuries, as often as any troublesom matter assaults or besieges it, might be able to draw it self together, and to shake off the enemy. For it seems, that the inordinate tremblings and shakings of the Heart, which are manifestly dif­ferent from its natural Pulse, proceed from the violent shaking of this Membrane.

As to the Cardiack branches sent from this insolding we observe, that they, be­cause destinated to a publick office, do therefore communicate and enter into the pairs of either side before they are inserted into the Heart; for which end the infold­ing is made before the Basis of the Heart, where the aforesaid shoots, from the wan­dring pair and many others, going out from either intercostal nerve, meet together. From that infolding, placed between the Aorta and the pneumonick-Artery, very many branches being sent forth above, cover over the Hemisphere of the Heart: but yet from these certain branches, carried under the Aorta, are brought into the left side of the said Hemisphere; and as other pairs tend towards the right side, one of the first of them, making a little handle, binds about the pneumonick Artery; then meeting with other Cardiack shoots, makes the lesser infolding, out of which bran­ches are sent forth into the right and anterior side of the Heart. That from the greater Cardiack infolding, nerves departing one from another, do institute contrary journies towards the Heart, it is indeed, that they might come to divers regions of the Heart without meeting one another, and might affect its Vessels respectively in their passage; to wit, the branches carried this way, insert their shoots into the Aorta, and from the others going that way, one compasses about the pneumonick Artery. The reason of both seems to be, that the blood might be either sooner or slower drawn from the bosoms of the Heart for its various need or necessity. For whilst the aforesaid nerves do both sustain its motion by their influx, and also mo­derate and temper it by their instinct, it so comes to pass from thence, that those [Page 152]Vessels also, being affected by the same nerves, do further compose themselves to the requisite Analogies and proportions of the Pulses.

Indeed there are many Nerves, and those conspicuous enough, which are inserted into the Heart, and cover its outward substance with shoots sent forth from all sides; yet it is not to be thought, that these nerves alone perform and sustain the undiscon­tinued motion of the Heart: because so small little ropes seem too unequal for the perpetual agitation of such a Machine. Yea it may be observed, that more shoots and fibres of nerves are distributed into the little ears of the Heart and the depending Vessels, than into its frame or substance. Further, it is obvious to any that will be­hold it, that there is a greater plenty of nerves destinated to the Lungs, Liver, Spleen, Ventricle, or Reins, than to the Heart it self; so that some Anatomists (as Fallopius says) were doubtful, whether there were any nerves that belonged to the Heart or not. But this being clear enough, that we may describe the motive power of this Clock or Machine stirred up by the help of some small nerves, as it were an explosive motion, we say that the substance of the Heart it self consists of a very fibrous flesh, and may rather be called a Muscle than Parenchyma or congealed substance: wherefore in this, as in o­ther Muscles, the implanted and proper fibres cause the local motion and constant sha­king; but by the inserted nerves is only conveyed the instinct of the motion or action; for the performing of which office, both fewer Nerves and fewer animal Spirits flowing in through their passages, do suffice. But indeed we suppose, that the animal Spirits implanted in the Heart, and abiding within its Fibres, did at first flow thither through the nerves, and that by this way their expences or loss are made up or supplied; yet that the animal Spirits, which seem to be dispensed to the Heart by so sparing an hand, may suffice for the actuating this perpetual motion, they receive continually subsi­diary Forces from the arterious blood. For elsewhere we have shewed, that in the Heart, as in the whole musculous stock besides, a sulphureous Copula, from the sug­gested blood, is joyned to the spirituous saline Particles of the implanted Spirits; which matter, whilst the Spirits are agitated, being at length struck off, and as it were exploded (just like the rarified and inkindled Particles of Gun-powder) for the effecting the motive endeavour, do blow up or intumifie the Muscle or the Heart it self; and so from the indiscontinued action of the Heart much of this sulphureous Copula, which is easily supplied from the blood, and less of the Spirits, which are brought by the passage of the nerves, is bestowed.

And here it may be rightly inquired into, whether the Pulse of the Heart so necessa­rily depends on the influence of the animal Spirits through the Nerves, that it being hindred, the action of the Heart should wholly cease? For the decision of this, we once made a tryal of the following Experiment upon a living Dog. The skin about the Throat being cut long-ways, and the Trunk of both the wandring pair being se­parated apart, we made a very strict Ligature; which being done, the Dog was presently silent, and seemed stunned, and suffered about the Hypochondria convul­five motions, with a great trembling of the Heart. But this affection quickly ceasing, afterwards he lay without any strength or lively aspect, as if dying, slow and impo­tent to any motion, and vomiting up any food that was given him: nevertheless his life as yet continued, neither was it presently extinguished after those nerves were wholly cut asunder; but this Animal lived for many days, and so long, till through long fasting, his strength and spirits being worn out, he died. The carcass being opened, the blood within the Ventricles of the Heart, and the Vessels on every side reaching from thence, to wit, both the Veins and Arteries, being greatly coa­gulated, was gathered into clotters; to wit, for this cause, because the blood, though for the sustaining of life, it was in some measure circulated, yet for the most part it stagnated both in the Heart, and in the Vessels. The cause of which stagna­tion I can assign to no other thing, than that the Praecordia, the in [...]ence of the animal Spirits being hindred, wanted its usual motions.

If it should be further demanded, from whence the animal Spirits (the passage of both the wandring pair being shut up) should be supplied to the Heart continuing still its motion; I say, that this may be done by the returning Nerves, as from the knots of which many Cardiack shoots and fibres proceed; and besides, the end of either nerve meeting with the nerve sent from the upper infolding, is united. But we shewed already, that the animal Spirits may be carried either this way or that way within the passages of the nerves; wherefore when the necessity of life urges, the provision of the Spirits, though lesser, being sent from the aforesaid infolding, is [Page 153]received by the tail of the returning nerve, and from thence by a retrograde passage it was derived into the Cardiack branches, and at length into the Heart it self. Fur­ther, there lyes open also another passage, and that perhaps more obvious, through the passage of the intercostal nerve: by this way in a man, as well as by the passage of the wandring pair, the Spirits are conveyed from the Brain to the Praecordia; yea also in Brutes a branch is carried into the Trunk of the wandring pair from the inter­costal infolding; so that by this by-path some little rills of the animal Spirits (if by chance their influence should be hindred through their wonted chanels) might be carried to the Heart. However that Experiment seems to conclude, that the motion of the Heart depends no less upon the inflowing of the blood, than upon that of the animal Spirit: the total privation of either takes away life; an Eclipse of the Spirits wholly takes away from the Heart its motive power; and by the defect of the blood (forasmuch as the sulphureous Copula is denied to the Spirit implanted in the Heart) the vigour and elastick force of the Heart is supprest, so that the Pulse being by degrees weakened, life is by little and little extinguished. Without doubt, in the finding out the tenour of the Pulse, we ought always to mind what the alteration of the ani­mal Spirits, and what the fault of the blood may bring to it.

There is yet another consideration concerning the Nerves reaching from the Trunk of the wandring pair to the Heart, to wit, that by their passage, not only the solemn influence and state of the Spirits, for the equally performing of the vital Function, is conveyed; but also the instinct of every irregular motion, stirred up in the Praecordia by the force of the Passions, is in some measure transferred this way. I say, as to these, we ought to discourse and to shew by what means, as often as the impression of any Affection exercises the Imagination, or rather the Appetite, presently the Praecordia are disturbed by the passage of the Nerves, and by reason of their various Affections the motion of the blood is diversly altered. But because in a man the ir­regular and extraordinary motions of the Praecordia depend on the intercostal Nerve as much as and perhaps more than on the wandring pair; therefore we think good to defer this Speculation till the Theory of that Nerve is proposed. In the mean time, we will proceed to the other branches of the wandring pair; and what next follows, we will inquire into the offices and uses of the returning Nerves.

The returning Nerve in the left side, going away from the wandring pair below the aforesaid infolding, and sent towards the Aorta, is reflected or turned back about its descending Trunk, from whence being carried upwards, it imparts shoots to the Muscles of the Trachea and the Larynx sent forth by a long tract from either side of the Nerve; then its top or height is united with a shoot meeting it out of the Gan­glioform infolding, Fig. 9. n. *** h. But the returning Nerve on the right side is reflected much higher about the axillar Artery, to wit, proceeding from the lower infolding of the wandring pair, and after the same manner is bestowed on the other side of the Trachea, Fig. 9. L. But either returning back about the knots of refle­ction, sends forth towards the Heart very many shoots and fibres, which are inserted into its little ears, the appending Vessels or its Infoldings.

What the chief use of this Nerve is, we have already shewn; to wit, being rolled about on both sides the Artery, as it were a Windlace, it causes the little rings of the Trachea or Weasand to be drawn hither and thither, like the folds of a pair of Bellows, both for breathing and making a sound. But indeed either Nerve, foras­much as it being reflected about the Artery, is carried upward into the part to be moved, doth move downwards the little rings of the Trachea or Wind-pipe by cer­tain shoots of it; also forasmuch as either is terminated in the Nerve, sent from the Ganglioform infolding, it carries upwards the folds of the Trachea by other shoots of it. Hence a reason may be given, why the returning Nerves being cut off, every Animal is presently dumb; to wit, because, unless the Trachea be moved, the breath being blown out, passing without any refraction through its cavity, as it were through a Pipe alike hollow in its whole passage, gives no sound.

Concerning these Nerves we ought to inquire, what is the reason of the difference, that the knots of reflection are not alike on both sides; also for what end the Car­diack branches proceed from both knots. As to the first, that the left returning Nerve, not as its pair, binds about the axillary Artery, some reason seems to be, be­cause the left axillary Artery, arising below, is carried as the right, by a bending, and not a straight passage, into the Arm; wherefore the little cord of the Nerve, compassing about its Trunk, hath no fixed, but a very moveable knot of reflection, [Page 154]for that it might easily slide from its place. But it may rather be said, that it is for other uses, and those more necessary, that these Nerves compass about those Ves­sels after that manner. For when they, as it were Reins or Bridles cast on the blood­carrying Vessels, by pulling them hither and thither, variously determine the course of the blood, it seems to be required, that one returning Nerve should bind together or constringe the axillary Artery, and the other the descending Trunk of the Aorta: for as often as there is need for the blood to flow forwards towards the Head more plentifully, the returning Nerves perform it easily, by pulling upwards the aforesaid Arteries: But the blood, after a sort, ought to be continually urged into the higher parts, lest otherwise by its weight it should turn too much downwards; wherefore in all Expiration or breathing forth, when the Trachea, drawing nearer together its solds, is contracted upwards, the blood about to descend through the Aorta, is snatched upwards by one tract of the nervous little cord, and in like manner, the axillary Artery in the right side being shaken with it, the blood flowing in the whole ascending Trunk of the Aorta, is driven upwards a little swifter.

But besides this continual and equal snatching up of the blood towards the upper parts, it is sometimes occasionally urged towards the Head by a more intense and quick motion of the Trachea, and also by a more full and swift course. For as often as any Animal grows angry, the voice presently shews signs of such an Affection, and oftentimes by chiding, they make it sharp; as men, when they are angry, chide or brawl, and Dogs bark: Now from such an intension of the voice and chiding, as the upper rings of the Trachea, a reciprocation being there made, are often struck to­gether; so the blood also (the A [...]ta being strongly drawn) is urged upwards by a copious afflux, so that it presently dyes the countenance and eyes of angry people with a redness, and induces to the Brain it self a greater heat and provocatives to anger, and a greater glowing or infiring to the Spirits by stirring them up. For the same reason, in Joy and Gladness, forasmuch as the Trachea is exercised by singing or laughing, the blood also is poured out more plentifully towards the exterior, and especially the upper parts.

And from hence the cause is plain, wherefore either returning Nerve sends forth Cardiack branches from the knot of reflection or turning back; to wit, that in those kind of affections, the notice of which the Trachea in sounds or voices gives by the help of the Nerves, the Heart it self by its means also might be affected. For so, as often as we wrangle or brawl, the Heart being irritated, presently inkindles the blood more, and drives it forward more plentifully, as food for those Affections, towards the Brain. Also in laughter, great rejoycing, or singing, by the passage of those Nerves, the Heart being brought into a consent or Sympathy, or joynt action, presently explodes or drives out the blood by a swifter pulse, and casts it hastily out, which otherwise would be heavy and troublesom by a slower motion or stagna­tion; wherefore those sort of actions, to wit, laughing and singing, are said to alleviate the Heart, because they make the blood more freely and readily to be pour­ed out of the bosoms of the Heart, and also, by the supplying help of the Lungs, to be emptied into the same.

Below the production of the left returning Nerve another noted Nerve is carried towards the hindermost region of the Heart, which being carried with a certain com­pass about its Basis, sends forth frequent shoots, which cover the left side of the hin­der Hemisphere, Fig. 9. [...]. Then this branch meeting with another pair sent from the opposite side towards the Heart, and distributing shoots into the right side of the binder Hemisphere, is united with it, Fig. 9. q.

This Cardiack branch, destinated to the hinder region of the Heart, is produced aparo below the rest, that it might be carried by it self to its Province without the meeting with or implication of others; the pairs are ingraffed on either side, that they might acoompany one another, and be together drawn in the same action of the Heart. It appears not plain, whether these nerves conspire with the other Cardiack nerves, arising above, reaching forth to the anterior Hemisphere of the Heart; or whether this pair effect not the Systole of the Heart, and the upper its Diastole. How­ever it is, certain shoots of the kindred or steck of either, being ingraffed with others of another stock, communicate one with the other.

The Trunk of the wandring pair sends forth on both sides very many noted bran­ches from the region of the Heart, which are spread on every side into all the Lobes of the Lungs, the Branchia of the Trachea, and the Coat of the Oesophagus hard by [Page 155]descending, Fig. 9. s.s.s. Those which go into the Lungs pass every where through their whole substance, following the ramifications of the Veins and Arteries, and the Pipes of the Bronchia, which chanels of blood and air they variously elimb over, and bind about through their whole tract.

When that so many noted branchings of the Nerves are bestowed on the Lungs, it is a wonder, that by some they should be thought to be insensible and immoveable of themselves. Yea it is doubted by many, whether these Bowels do cause the mo­tions of the Systole and Diastole of themselves by their own endeavour. For that it is a received Opinion, That this reciprocation of the Lungs doth proceed wholly from the motion of the Thorax, and doth obey or observe its dilatation or constriction with a certain necessary dependency; viz. that the Breast being dilated or spread open after the manner of a pair of Bellows doth compel the ambient Air into the Trachea, which rushing into the Lungs, blows up and distends them; then the same Breast subsiding or sinking of it self, that the Lungs being pressed together with the weight of it, do breath forth the Air before intruded. In truth, however that I might judge, that the Diaphragma and the Muscles of the Breast do conduce much to Respiration; yet that these patts should perform this office alone, and that the Lungs are merely pas­sive, I cannot grant. For Respiration is chiefly instituted for the sake of the blood and the Heart, and its act is wont to be determined according to the various dispo­sition of these, and to be altered every minute of an hour almost according to the manifold necessity of the Pulse. But indeed the Lungs themselves are they (and not the Diaphragma or the Muscles of the Thorax) which the blood, boiling out of the Heart, passes through, and continually affects according to its temper, and the tenour of the Pulse: wherefore from hence it may be concluded, That the Lungs themselves do conceive the first instincts of their motions, and by the help of the aforesaid Nerves, do in some measure exercise themselves, and endeavour the Systole and Diastole, and design them according to the sense of its proper necessity; but when in these, Fibres requisite for local motion are wanting, therefore the Diaphragma and the Muscles of the Thorax help continually the endeavours of the Lungs, and by the cooperation of these, compleat breathing is effected. And so when Nerves of a twofold kind, to wit, some from the Spine being inserted into the Muscles of the Diaphragma and the Thorax, and others from the wandring pair distributed into the Lungs, actuate the Organs of Respiration; for that reason it comes to pass, that the act it self of Respiration, of it self unforced and involuntary, may be at our pleasure somewhat restrained, interrupted, and diversly altered. The Sym­praxis or joynt action of the Nerves of either kind, in the work of Respiration, shall be shewed hereafter, when we shall speak particularly of the Nerve of the Dia­phragma.

It yet appears more plain, that the Lungs are oftentimes the chief in the act of Respiration, because they being irritated from strange and improportionate objects, presently conceive irregular and violent motions; as when a vehement Cough is stirred up for the exclusion of any troublesom thing; to which motion the Diaphragma and the Muscles of the Thorax presently obey. In like manner, in difficult and sighing breathing, or any other ways unequal, its first instinct for the most part is begun by the Lungs; yet sometimes when the exterior Organs of Respiration are excited into irregular motions, the Lungs also are compelled to follow their irregularities; so when the Diaphragma after a manner begins laughter, the Lungs perform the same with a following cackling sound: so all the Organs of Respiration intimately conspire and agree among themselves, that although one of them do a thing inordi­nately, rather than there shall be a Schism, the rest do imitate or follow its irre­gularity.

But that the Nerves, following the Arteries and Veins through the whole frame of the Lungs, do variously bind about and cloath their Trunks with a thick series of shoots, the reason seems to be, both that the Coats of the Vessels being gifted with a constant influx of animal Spirits, might imitate the motion of the Heart; and by that means, by a continual pulsation of the Arteries and the constriction of the Veins, they might easily carry the blood in this its more short lustration through the Lungs; and the rather, that the pneumonick Vessels, being bound about with such Reins of Nerves, might moderate the course of the blood according to the forces and in­stincts of the Passions. For whenas the exterior circulation of the blood depends upon this interior; as the blood is commanded to pass sooner or slower through the [Page 156]Lungs, or to stay there and be hindred, the excursion and return of it also from or towards the Heart is wholly performed. In Joy or Anger, because the Lungs ra­pidly transfer the blood out of one bosom of the Heart to the other; therefore its swifter and more plentiful flowing out into the outward parts, follows. In like manner, in Fear and Sadness, for that the Lungs (its Vessels being strained together) deliver the blood to the Heart by the Veins, and do not then presently carry it back by the Arteries, the outmost region of the Body is destitute of its due influx. Not­withstanding these kind of pathetick snatches of the blood are in some measure perfor­med, because its Vessels are bound about in other places in like manner with the Nerves. If at any time Spasmodick Affections should afflict the pneumonick Nerves from a morbific cause, so that being twitcht with inordinate motions, they should pull or draw together here and there the Arteries and Veins which they embrace; for that cause, the blood either too much flowing out of the Lungs, makes them to flag, and to fall together into themselves, so that drawing to them copiously the Air, they do not easily render it back again; or, which frequently happens, the blood being detained within the Lungs, and there stagnating, stuffs them up, and holds them a long while stiff, that they cannot inspire or drawn in the Air. The Sym­ptoms of either kind ordinarily happen in the Hysterick distempers, and in some Hypochondracal. Yea sometimes the Bronchia themselves are pulled together by the like Convulsion of the Nerves, and are hindred in their motion, so that they can­not take in and send forth the Air after its due manner, as may be seen in Asthma­tical Fits. The distempers of which sort are oftentimes produced by the fault of the Nerves, without any implanted Dyscrasie or evil disposition of the Lungs. I have sometimes observed some Cases of sick people, in which, when at one time the morbi­fick matter besieging the Brain, had induced Lethargick or Vertiginous Symptoms, a little after the same matter occupying or possessing the origines or middle processes of the nerves belonging to the Lungs, has suddenly excited a most horrid Asthma without any previous Cough or Catarrh.

But that out of the same tract of the wandring pair many shoots are distributed into the Lungs, and also many others into the Coats of the Oesophagus; from hence a rea­son may be given, why a troublesom Cough oftentimes causes Vomiting and a sub­version of the Ventricle; why also on the other side a perturbation of the Ventricle so frequently induces a troublesom endeavour of Coughing. I have known in Hypochondriacks, that aliments of ill digestion, taken into the Stomach, have presently ex­cited a vain and very pertinacious Cough; in the mean time, that the Lungs were free from any consumptive disposition. The cause of either distemper seems to be, that when the nerves, disseminated in either part, are taken with a Convulsion, often­times those which are of the other part, are drawn into a consent of the same distem­per. Perhaps from hence it happens, that sometimes an Asthma is induced by reason of the evil of the Ventricle, and that that distemper (as Riverius observes) is often wont to be cured by an emetick Medicine.

After so many branches and shoots have been sent from both sides the wandring pair, at length its Trunk is divided below the Lungs into two branches, viz. the ex­terior and interior; either of which inclining towards the pair of branches on the other side, are united to them, and after a mutual communication they constitute the two Stomachical branches, viz. the superior and the inferior, Fig. 9. t. u. w. x.

It is worth observing, with what wonderful artifice either Trunk of the wandring pair do communicate one with the other with two branches, as it were two hands meeting one the other, that the influence of either nerve might equally reach to every region and part of the Stomach. For whenas either Stomachical branch, to wit, both the upper and the lower, is carried together from the two branches coming out from either side of the wandring pair; it is provided, that the Tributes of the Spirits de­stinated to the Ventricle, should be at once certain and very plentiful. For what appertains to the performing the action of this Bowel or Chylification, the Spirits flowing in from either side, are abundantly distributed into the Orifice, and from thence into all its parts and private places; and by that means it comes to pass, that the Stomach dissolves bodies beyond the force of any Chymical Menstruum. Then besides, as to the feeling or sense of the Ventricle, or the affection of it from things ingested; it is carried also towards the Head by a double way (whereby the passage may be the more certain) to wit, by either Trunk of the wandring pair; that for that reason being indued with a most exquisite sense, it might not be deceived con­cerning [Page 157]its objects; and if that any thing inimical or contrary to it, should lye hid among what is eaten, it might discern it and thrust it out of its own accord, or at least by the knowledge only of the Cerebel.

That from the same double Trunk of the wandring pair, from whence the Cardiack Nerves arise a little above, the Stomachical branches also proceed, the cause is plain wherefore the Heart it self hath such a Sympathy with the Stomach, so that its Deli­quium or Swooning follows upon any great pulling or hawling of this.

Either Nerve of the wandring pair is terminated in the Ventricle it self: for after the eighth Conjugation hath made as it were an high road for the passage of the ani­mal Spirits to the Praecordia and to this noble Bowel, it puts a bound to it self; nor indeed does it seem meet to have its branches stretched out any further to the Viscera of the lower Belly: because it seems an unworthy thing, that the same path which leads to the chief office of nutrition and to the Palaces of life it self, should lye open to the more vile Intestines also, and the sink of the whole body. And truly, although the ample path and broad way of the wandring pair is not produced be­yond the Ventricle, yet because a frequent commerce happens between this and the Praecordia and the other inferior parts; therefore between the Stomach and the other Bowels, though of a more base use, certain Fibres, as it were smaller paths, are reached forth, in which, at least little bands of Spirits, like Discoverers or Mes­sengers, run to and fro.

CHAP. XXV.

AFter the unfolding of the Nerve reaching forth to the Praecordia and the Ven­tricle, we are led by the series or order of the inward parts to the describing a Nerve akin to this, and which reaches forth its branches to the furthermost Province, to wit, to all the Viscera or Inwards of the lower Belly contained below the Ventricle. This is commonly called the Intercostal, because that going near the roots of the Ribs, it receives in every one of their Interstices a branch from the spinal Marrow. Its beginning is not yet sufficiently detected; for by most Anatomists it is wrongfully taken for a branch of the wandring pair, though indeed the wandring and the inter­costal pair do communicate among themselves by branches sent forth one to the other; yet as to both their beginnings, Trunks and wandrings up and down, they are plainly distinguished. If that this latter Conjugation, being denied the title of a peculiar nerve, ought to confess it self of another stock, certainly it owes nothing to the wandring pair, but should borrow its original from the Nerves of the fifth and sixth pairs; for two or three shoots being sent back from those nerves going out to­wards the Eyes and Face, go into the same stock or Trunk, which is the Trunk of the intercostal nerve, as we have intimated before.

The intercostal Nerve being constituted after that manner, and going out of the Skull at a proper hole, presently contains the Gangliosorm infolding, near to ano­ther the like infolding of the wandring pair; into which two nervous Processes are carried from the last pair within the Skull, or the first Vertebral. From that infold­ing one shoot is sent forth into the Sphincter of the Throat, and another noted one into the Ganglioform infolding of the wandring pair. Then this nerve descending towards the Vertebrae, hath in the middle of the Neck another far greater infolding, into which an ample nerve, from the neighbouring Vertebral pair, is inserted; but from the same many nerves, which respect the Pracordia, are distributed on every side: For two or three shoots are sent forth into the nerve of the Diaphragma, and one shoot into the returning nerve; besides, numerous fibres and shoots are carried both into the returning nerve, and towards the Trachea, which are inserted into its Coats, and into those of the Oesophagus, and into the blood-carrying Vessels. Fur­ther, one branch descends into the Trunk of the wandring pair, and two noted nerves into the Cardiack infolding; then a little lower another nerve by it self, proceeding out of the intercostal Trunk, is inserted also into the Cardiack infolding: which noted branches sent down on both sides from the intercostal nerve, for that they joyn [Page 156] [...] [Page 157] [...] [Page 158]together with others derived from either Trunk of the wandring pair, make the Cardiack infolding it self. But these Cardiack branches from the intercostal nerve, as also the Cervical infolding, or that in the hinder part of the Neck, whence they proceed, are peculiar to men, and are wholly wanting in brute beasts.

The intercostal Trunk descends from the cervical infolding towards the chanel­bone, where being about to enter the cavity of the Breast, it falls upon the axillary Artery, as it were in right Angles, and strains or binds it; from whence it is drown­ed or hidden in the Thorax near the roots of the first and second Ribs; and there re­ceiving three or four branches from the Vertebral nerves next to those uppermost, constitutes another infolding, which is commonly called the Intercostal infolding. The uppermost of these Vertebral nerves coming to this infolding in its journey binds the Vertebral Artery, and almost compasses it about. In Brutes by this nerve which comes upon the Vertebral Artery, the intercostal infolding communicates with the root of the nerve of the Diaphragma, and not by any other means, unless by small fibres sent forth from the lower part of the infolding into the Vertebral nerves. Fur­ther, in Brutes a noted branch is carried from this infolding into the Trunk of the wandring pair. But in Man the intercostal Trunk passes through the cavity of the Thorax without any communication had with the other parts; unless that from hence in its whole descent, running near the roots of the Ribs, it admits in every one of their interspaces, and from thence even to the Os sacrum from between the knots of the Vertebrae, a Vertebral branch.

The intercostal pair sends forth a noted branch on either side, where having gone through the cavity of the Thorax or Breast, it comes over against the bottom of the Ventricle, which tending towards the Mesentery, constitutes the chief infoldings of it. But there are seven Mesenterick infoldings, viz. five great superior, and two less inferior: out of all which, numerous shoots and fibres are sent forth together into the parts which they respect, and into the neighbouring infoldings. The Mesenterick nerves, which are carried into these infoldings, and the infoldings themselves, and also the fibres and shoots, which flow out from them on every side, like rays of light, are disposed according to the following manner both in Man and in the more perfect Brutes.

The Mesenterick branch therefore in the left side going from the intercostal Nerve, and bending downwards, is parted into two noted shoots: the greater of these bend­ing back upwards towards the Stomach, diffuseth it self presently into an infolding, as a narrow rivulet into a spacious Pool. From this infolding numerous fibres and shoots go forth as it were in four bands. The first of these, and which is the greatest bundle of its fibres, being carried into the Ventricle, is bestowed partly in the bot­tom of it, and partly these fibres are met, and ingraffed with others sent from the-Stomachical branch. The other maniple or band of nervous Fibres goes forth from this infolding to the Spleen, where the nerves accompanying the sanguiferous Vessels, and variously binding them about, are dispersed into the more inward frame or sub­stance of the Spleen; yet out of which going towards the Spleen, some shoots follow­ing the short Vessels, are carried into the Stomach. The third Company of nervous Fibres is inserted between this infolding and the Hepatick or that belonging to the Li­ver, placed in the right side over against it. Lastly, the fourth Conjugation of Fibres knits together this and the greatest infolding of the Mesentery lying under it.

The lower shoot of the Mesenterick branch, which is on the left side, increases into an infolding, to which the next Vertebral branch, destinated to the intercostal Nerve, is carried. From this infolding the chief bundle of nervous Fibres is carried into the left Kidney, and before the Fibres enter the Reins, they bind and variously compass about the emulgent Vessels. Further, between this infolding and the great­est of the Mesentery many Fibres are stretched out; from hence also many shoots are distributed into the atrabilary Chest, or the Receptacle of the Spleens excrements.

In the right side the Mesenterick branch being sent from the intercostal Trunk, and being in like manner twofold, contains in its upper shoot the Hepatick infolding; out of which the greatest bundle of nervous Fibres is carried towards the Liver; nu­merous shoots of which accompanying the blood-carrying Vessels, greatly beset, and as it were cloath with a little net the Trunk of the Hepatick Artery: which fibres and shoots, being carried higher, are distributed into the Liver, the Gall-chest or bag, the passage of the Gall, the Pylorus, and the Pancreas. Further, many Fibres, which are of this Conjugation, meet with Fibres sent from either Stomachical nerve, and [Page 159]are ingraffed into them. Another handful of nervous Fibres is stretched out between this infolding and the opposite infolding belonging to the Spleen, and another be­tween this and the greatest infolding of the Mesentery; yea, there is some communi­cation had between this and that belonging to the Kidney lying under the same side by a large shoot sent down.

The lower shoot of the right Mesenterick branch, like as it is in the opposite side, contains a sufficiently noted infolding nigh the atrabilary Chest; to which presently the intercostal Nerve imparts its Vertebral branch received below. From this in­folding the chief bundle of nervous Fibres destinated to the Reins, embraces the blood-carrying Vessels in like manner as in the opposite side; also many fibres and shoots are stretched out from this infolding to those near, viz. the Hepatick and the greatest of the Mesentery; yea, certain Fibres are dispersed from the same into the atrabilary Chest.

After this manner either Mesenterick branch being carried from the Intercostal pair, and being presently twofold, immediately constitutes two infoldings in either side. In the midst of these the greatest infolding of all stands like the Sun in the midst of the Planets; from which numerous shoots and fibres are dispersed into all the parts of the Mesentery; which indeed following the blood-carrying Vessels in their whole process, climb over and bind about the same. Moreover, between this infolding and every one of the four aforesaid is produced a peculiar little bundle of Fibres. Besides, in the female Sex, from hence some shoots are carried into the Glandula's of the Womb, commonly called the Stones. But from the Mesenterick branches, which constitute the former infoldings, no noted branches, but only little shoots, are sent into this infolding. Yea the chief Nerve which is inserted to this, and seems to be the primary for the conveying of plenty of Spirits into it, and a broad way, is carried from a certain small infolding far lower nigh the straight Intestine; which infolding, together with the other neighbouring one, that we call the lesser infoldings of the Mesentery, shall be described presently. In the mean time, that we may proceed to them in order, we will follow the passage of the intercostal Nerve.

Below the Mesenterick branches, from which the aforesaid superior infoldings are constituted, the intercostal Trunk descends between the Muscles of the Loyns, and bestows every Vertebral branch, admitted in its descent, upon some internal parts.

For the Vertebral branch brought to the intercostal Trunk nigh both Kidneys, is carried into the Womens Testicles, then some following into the Ureters. From the Region of the twenty seventh Vertebra one Vertebral branch and two others, going from the intercostal Trunk, tend towards the straight Intestine, and there they meet with three pairs sent from the other side; all which being united, constitute the in­folding, which is the lowest of the Abdomen. From this infolding a noted Nerve, being carried upwards, is brought into the greatest infolding of the Mesentery, which in its journey receives one and then another shoot sent down on both sides from the intercostal Nerve; and there, near its bounds, distributes some shoots into the Glan­dula's of the Womb.

But from the lowest aforesaid Infolding, a Nerve going towards the upper Infold­ings, about the space of an inch, constitutes another lesser infolding in the neighbour­hood; out of which one Nerve tends upwards, and another opposite straight down­wards. The former of these is carried into the greatest infolding of the Mesentery, and in its whole passage stretches under the straight Intestine, and part of the Colon, and inserts into them many small shoots. But the other Nerve descending from this infolding towards the Anus under the inferior part of the straight Intestine, imparts to it also frequent shoots; so that this infolding, the least of all those which are with­in the Abdomen, seems to be constituted for the sake of this Nerve only, to wit, which lying under the straight Intestine and part of the Colon, is inserted into the greatest infolding of the Mesentery.

From the lowest neighbouring Infolding, to which this least owes its original, two Nerves going out, and being sent down into the Pelvis, cause there two infoldings, viz. one in either side, in which the Nerves coming from the Os sacrum, and ingraf­fed with the former, meet; from which also the Nerves distributed into the adjacent parts, serve unto the several Excretions, viz. of the Urine, Dung, and Seed made in that place: for two Nerves enter into the end of the straight Intestine, and as many into the Womb or Prostates; but one, and that a noted one, is carried into the Bladder.

But that we may return to the Intercostal pair, after either Trunk of it had sent forth three branches, out of which the aforesaid lower infoldings of the Abdomen are mediately or immediately made, it descends straight towards the Os sacrum, and in its journey sends forth yet one or two branches into the Ureters: but as soon as it is come to the beginning of the Os sacrum, both nerves mutually inclining themselves to one another, are demerged within the bending of the same bone, and there nigh its declining, and then in its descent, they seem to be knit together upon it by two or three processes; and so at length either nerve ends in very small fibres, which are distributed into the Sphincter of the Anus. But sometimes either nerve joyn together into a round infolding nigh one transverse process, out of which single infolding the like very small Fibres are produced. Further, many others from the last Vertebral Nerve meet with, and are ingrassed with these Fibres from the intercostal pair in­serted into the Anus.

CHAP. XXVI.

THE beginning of the Intercostal Nerve are two or three shoots reflected or turned back from the Nerves of the fifth and sixth pair, and united into the same Trunk, Fig. 9. D. a. a. b. Here we may wonder at the birth of this Nerve, as it were borrowed; for it grows as a shrub upon another tree or shrub; and therefore dispenses the common virtues and influences of either with a double branch­ing, viz. both its own and that of its parent: by which ramification or branch­ing it comes to pass, that there are very quick commerces and consent between the conceptions of the Brain and the affections of the Praecordia, also between the Actions and Passions almost of all the parts of the whole Body, which belong to the involuntary Function. For in that the Trunk of the intercostal Nerve proceeds from the Nerves of the fifth and sixth pair nigh their beginnings, that is a sign that both the influence of the animal Spirits, and the instincts for the performing of motions, are derived chiefly into it from the Cerebel; to wit, from whose annular process the aforesaid pairs of Nerves arise. But forasmuch as the same intercostal Nerve is rooted in their Trunks, and not immediately in the Cerebel; this is the reason why the Eyes, as also the parts of the Mouth and Face, to which the fifth and sixth pairs have regard, do answer so readily and unknown to the Cerebel, as it were by the same act, to the motions of the Praecordia and Viscera, which the intercostal Nerve effects; and on the contrary, the motions of these presently follow the action of those. As for example, in Sneezing as soon as the nervous Fibres besmearing the Nostrils, are wrinkled together by the pulling, presently by the passage of the inter­costal nerve the Diaphragma, by reason of a more deep inspiration or drawing in the breath, is for some time depressed; then the Cramp of the Nostrils remitting, the Midriff also being violently drawn back, causes a more strong breathing forth with a vehement blowing of the Air. In like manner on the contrary, when by a tick­ling made upon the Ribs, the Diaphragma being affected with a Spasm, moves to a cackling noise, the Face and Mouth are pathetically figured with it into laughter.

The intercostal Nerve being slid out of the Skull, presently constitutes the Gan­glioform infolding, Fig. 9. G. it being after the same manner in the Trunk of the wandring pair. What the use of these infoldings is in general, we have already shewn; and clearly for the same reason in this place in the intercostal Trunk, where it receives into it self some nerves from elsewhere, and sends forth others from it self into the neighbouring parts, this infolding, as it were a knot in the stem of a flou­rishing Tree, is made, that it may be as it were a diverting place for the mani­fold tendency of the Spirits. As to the adventitious Nerves it is observed, That by them plenty of subsidiary Spirits are transmitted hither, only from the spinal Marrow, but by a manifold and frequent passage; wherefore in this infolding, and again in [Page 161]the following, then a little lower, nigh the several junctures of the Vertebrae, the Ver­tebral branch comes to either Trunk of the intercostal pair: this seems to be so con­stituted for many uses. First, That the intercostal Nerve, by the reiterated fastening to the solid parts, as it were by a frequent stay, might become the more firm for the making of a long journey, when otherwise its little rope, by too much stretching out, might be easily broken. Secondly, By this means it comes to pass, that the nerves which are the Executors of the spontaneous, and those of the involuntary Function, might have both a more certain commerce together, and might be sometimes excited into mutual succors. Hence Respiration and some other Acts, especially what concerns the Act of Venus, participate of either Regiment, so that sometimes they follow the will, and sometimes draw it even by force or unwilling. Further, when at any time the stock of animal Spirits is deficient in either Province, supplies of them are sought from the other: to wit, (as we hinted above) if the influence towards the Praecordia be shut up through the ordinary passages, viz. the internal nerves, their passages requisite for the sustaining of life, might be supplied by the Vertebral branches: yea it is probable in the partial Apoplexie, and in the Incubus or Night mare, when the Cerebel being affected, the Spirits destinated for the Heart, suffer an Eclipse in the Fountain it self, that through these Emissaries, to wit, the Vertebral branches inserted into the intercostal pair, some extemporary Subsidies are carried for the actuating the Heart. Thirdly, The Vertebral branches by so frequent an insertion, are added to the intercostal nerve, perchance in some respect for this end also, that the superfluous or excrementitious humidities, heaped together about the spinal Mar­row, might be sent away by these Processes: for indeed we have already shewn, that a certain humor doth abound within the Head, the medullar Appendix, and nervous System; which oftentimes (when it becomes watry, or abounds above measure) be­gets a serous heap in those parts: wherefore when the branches of the intercostal nerve are terminated into the Mesentery, Kidneys, Intestines, and some Genital parts, it is probable they do transfer into these sinks superfluous humidities, not only their own, but also of another sort, to wit, those received from the spinal Nerves.

As to the Nerves, which as Emissaries, are carried from the aforesaid Ganglioform infolding into other parts, we observe; first, that a noted shoot is carried from hence into the Sphincter of the Throat, Fig. 9. [...]. This nerve in the Sphincter of the Throat corresponds with others akin, arising higher from the fifth pair, and di­stributed into the parts of the Palate and Mouth, and is helpful to them in the business of chewing: for when the maxillar branches of the fifth pair should perform their work for the chewing of the food taken in, the task of this nerve mediately arising also from the fifth pair, follows, to wit, whereby the Throat being opened, the chewed meats may be thrust forward into its passage.

Another shoot is stretched out from this infolding into a like infolding of the wan­dring pair placed near, Fig. 9. a. The reason of this insertion is delivered above, where we treat of the wandring Pair. But it may be observed further concerning this; when so nigh a communication happens between these infoldings, and when shoots are sent from one of them into the Muscles of the Larynx, and from another into the Muscles of the Throat, from hence we may give a reason, why in Hysterick distempers and in some Hypochondriacal there is so frequent and familiar a Symptom of the sense of choaking in the Throat. For a Cramp or Convulsion being begun in any nerve, it is wont to creep forward further by the passage of the same, and so to invade sometimes these parts, sometimes those successively. If therefore at any time a Spasm arises any where in any nerve of the wandring or intercostal pair, and from thence tending upwards or downwards, shall come to either infolding, pre­sently both being affected, and the Muscles of the whole neighbourhood being con­tracted, a bulk or Tumor like a Globe or round thing in the Throat is excited with a sense of choaking.

The intercostal Nerve descending a little lower, contains in the neck another greater infolding proper to man, to which a noted Vertebral nerve is inserted also, out of which many nerves destinated to the Praecordia, are sent forth on either side, Fig. 9. T. As to the principal parts, to wit, the Brain and Heart, there is no such great difference between a Man and a Brute, as there is about the passage of one to the other, or the commerce that those parts have mutually among themselves. In either kind, for the exercise of the vital Function, the animal Spirits are derived [Page 162]from the Head, with a constant emanation into the Heart; to which sort of influence of theirs the passage of the wandring pair of nerves seems sufficient: wherefore in most Brutes the passage to the Heart and its Appendix lyes open only by this way, and scarce at all by any nerves of the intercostal pair. But in Man the intercostal nerve, besides its offices in the lower Belly, common to him with other Animals, serves in the place of a special Internuncius also before the Cloister of the Breast, which bears the mutual senses of the Brain and Heart this way and that way, or to and fro. For when, besides the nerves of the wandring pair, stretched out also into the humane Praecordia, (which certainly seem sufficient for the executing of the offices of the Function merely vital) so many noted branches are sent forth from the aforesaid intercostal infolding, what kind of office should be attributed to these, unless that they should contain the animal Spirits, by whose work and ministry the mutual respects and affections of the Brain and Heart should be communicated to one another? Whilst I consider this difference of either kind, it comes into my mind, that Brutes are like Machines framed with a more simple furniture and with less workmanship, and therefore furnished with a motion of one kind only, or determi­ned for the doing still the same thing. But in Man divers series of motions, and as it were complications of wheels within wheels, appear. For indeed, by the passage of the aforesaid infolding, the conceptions of the Brain presently affect the Heart and its Vessels, and cause the rest of the Appendix, together with the Diaphragma, to be moved. Hence the motion of the blood and its inkindling in the Heart, toge­ther with the Pulse and Respiration, are altered: and for that cause, from the Heart being altered, not only impressions are retorted upon the Brain by the passage of the same nerves, but also the blood it self, its course being changed, drives to the Brain with a different or unaccustomed fluctuation, and so by moving the animal Spirits with various impulses, causes first one sort of conceptions, and then others to be produced: and so by reason of these reciprocal affections of the Heart and Brain, which are wont by a long series to be propagated vicissively, a multiplicity of thoughts and Phantasms arises. Hence both the ancient Divines and Philosophers placed wisdom in the Heart. Certainly the Works of Prudence and Vertue depend very much on the mutual commerce which happens to the Heart with the Brain: because, that cogi­tations about the acts of the Appetite or Judgment may be rightly described, it is be­hoveful for the hood of the blood to be restrained in the Breast, and the inordinations of it and of the Heart it self to be governed by the Nerves, as it were by Reins, and to be composed into requisite and apt motions. We might say more concerning this, but that this Speculation is from our purpose, and belongs more properly to Patho­logy or the Doctrine of the Passions of the Soul. In the mean time, we may refer hither one or two Observations taken from Anatomy.

When of late we had dissected the Carcass of a man that was a Fool from his birth, we could find no defect or fault in the Brain, unless that its substance or bulk was very small. But the chief note of difference which we observed between the parts of this man and of a man of judgment, was this, That the aforesaid infolding of the inter­costal Nerve, which we call the Internuncius of the Brain and Heart, proper to man, was very small in this Fool, and beset with a weaker guard of Nerves.

Whilst we were writing these, we made an Anatomy of a Monkey, whose Brain differed little from that which is seen in a Dog or a Fox, unless that it was much more capacious in the proportion to the bulk of his Body, and the turnings and wind­ings of it were larger. The orbicular Prominences called Nates and Testes, also the ringy Protuberance, sent down from the Cerebel, came nearer the figure and mag­nitude of those parts in a man. But what occurred chiefly worthy noting, was this, viz. That the intercostal Nerve, although even as it is wont to be in other Brutes, being included in the same sheath with the Trunk of the eighth pair, was carried through the Neck, yet departing from this Nerve near the Chanel bone, before it was inserted into the infolding, placed nigh the roots of the upper Ribs, did send forth some shoots into the Heart and its Appendix, and certain Fibres into the nerve of the Diaphragma: which perhaps partly is the reason, why this Animal is so craf­ty and mimical above other Beasts, and can so aptly shew and imitate, not only the gestures, but the passions and some manners of a Man. But we will proceed to the explication of the intercostal Nerve from whence we have digressed.

We have already intimated for what use the Vertebral branch is inserted into its cervical infolding. There is the same reason for this as for the other Vertebrals, [Page 163]which communicate with the intercostal Nerve almost in its whole passage. But for that the nerve of the Diaphragma is radicated in the same Vertebral nerve, from whence a branch comes into this infolding, I say from that a reason may be taken, why the motion of the Diaphragma intimately conspires with the Praecordia, yea and with the conceptions of the Brain: which kind of Sympathy of the Diaphragma with the other parts, because it is requisite to be more strict and noted in man, it is ob­served, That not only the Vertebral branch cometh between the infolding and the root of the nerve of the Diaphragma, but two and sometimes three nerves are sent from this infolding into the trunk it self of the nerve of the Diaphragma, Fig. 9 [...]. [...]. Truly from hence not only the joynt action or Sympraxis of the Diaphragma with the Praecordia may be derived; but also the genuine cause is here manifest, why Risibility is a proper Affection of a man. For as often as the Imagination is affected by any pleasant or wonderful conception, presently the Heart desires to rejoyce, and as it were by shaking off its load to be eased: wherefore that the blood might be more swiftly emptied out of its right bosom into the Lungs, and consequently out of the left into the Aorta, the Diaphragma, instigated by the passage of the nerves going out of this infolding, is drawn upward by a more rapid Systole, and raises up the Lungs, as it were making iterated leaps, and causes them, by their more frequent striking together, to drive out both the Air and the blood. Then forasmuch a; the same intercostal Nerve, which communicates lower with the nerve of the Diaphragma, is continued also higher with the maxillary Nerves, a cackling being made in the Breast, with it the gesture of the Mouth and Face pathetically answers.

One or two noted shoots and many nervous Fibres are carried from this infolding into the returning Nerve, Fig. 9. ζ. Certainly the reason of this communication seems to be, that the Diaphragma and the Heart it self (into which nerves are sent from this infolding) might yet more conspire with the rough Artery (which the returning nerve affects) in its various actions, and especially in laughing, weeping, and singing. Moreover, when the returning Nerves, by pulling upwards the Trunks of the Aorta, cause the blood, for the stirring up some Affections, to creep more swiftly towards the Head, they may in the performing that office be much helped by the associate labour of the Nerves sent from this infolding.

From this infolding in the Neck many small fibres and shoots are spread into the sanguiferous Vessels, as also into the Coats of the Trachea and the Oesophagus, Fig. 9. ibid. As to what belongs to the former that respect the Trachea and the blood-car­rying Vessels; their office is, that they may respectively draw together and spread abroad those chanels of inspired and exspired blood and Air, according to the way and manner wherewith the Pulse and Breathing ought to be performed; whereby the motions of either might be the better retarded or accelerated, according to the ne­cessities or requirings of the Heart. Then numerous Fibres are stretched out from this infolding into the Coats of the Oesophagus placed near, that by this means the admirable consent between the Heart and the Stomach, by reason of the Nerves being reached forth from this infolding and from the wandring pair to both, may be produced.

Concerning the Cardia [...] branches sent from this infolding, we need not discourse any more: after having but now intimated, that these were as it were Internuncii pe­culiar to men, which carrying to and fro the reciprocal impressions of the Brain and Heart, cause Commerces in both Kingdoms. But forasmuch as Nerves of a double kind, viz. of the wandring and intercostal [...]air, respect the humane Praecordia, lest the gestures of one should be different from those of the other, therefore the Cardiack branches, which are of either family, partly communicate in the same infolding, and are partly inoculated mutually by shoots sent forth before they are distributed into the Heart it self.

Below the Cervical infolding, the intercostal Trunk being demersed within the Thorax, admits three Vertebral Nerves arising higher, and constitutes the other in­folding, which is commonly called the Intercostal, but more properly the Thoracical infolding, Fig. 9. Θ. In this place the intercostal Nerve being about to pass into its last and more large Province, viz. the Viscera of the lower Belly, and therefore seeking aid for the journey, and as it were a Viaticum for it self, it gets together in this infolding an increase or aiding forces from the Vertebral nerves, and afterwards receives lower others fresh nigh the several knots of the Vertebrae; because it will have need of a great stock of Spirits, which it must bestow on the Mesenterick infoldings, and on other parts of the Abdomen.

That this Nerve about to enter the Thoracical infolding, doth bind the Chanel­bone Artery, Fig. 9. l. and that the superior branch of the Vertebral, being sent into the same infolding, doth bind about the Vertebral Artery, Fig. 9. [...]. the reason of both seems, that the blood, for the uses and necessities of the lower Viscera (to which the intercostal Nerve from thence serves) may be driven forward with a more plenti­ful afflux downwards: which thing those Nerves easily do by pulling together the blood-carrying Vessels towards their infolding; so that they attempt this snatching of the blood in opposition to that which the returning Nerves perform. And indeed when the blood, tending upwards and downwards, is wont sometimes to flow too much towards either bound, sometimes to be wanting; therefore the nerves, as it were an incitement or remora, are variously disposed both in the upper and lower re­gion of the Circuit about the sanguiferous Vessels. After what manner this Thora­cical infolding is in brute Beasts, shall be particularly shewn hereaster. The inter­costal Nerve in a Man, both in this infolding and in the whole descent through the Thorax, receives many Vertebral nerves, as if sparing of its own stock, and greedy of anothers, but sends forth from it self not a shoot: whatever of Spirits is remain­ing either from the influence above, or comes to it by the by, is reserved wholly for a largess to be bestowed on the Viscera of the lower Belly. But after what manner, and by what passages of nerves that is dispensed into the several parts, we will unfold in the following Chapter.

CHAP. XXVII.

AFter the intercostal Pair hath past through the hollowness of the Thorax without any expence of Spirits, unless in the Neck-infolding, at length it sends down from the region of the Ventricle on both sides, a noted Branch; either of which presently becoming divided into two, constitute two pe­culiar Infoldings on either side; but one infolding arises in the midst of them, as if common to either side. Of the infoldings which are on the left side, one respects the Kidney, and the other the Ventricle with the Spleen; but of those which are on the opposite side, one respects the right Kidney, and the other the Liver and its neigh­bouring part. In the midst of these, the infolding proper to the Mesentery and the biggest, is placed as the Sun among the other Planets. Further, from these are sent forth one to another and into the neighbouring parts numerous Fibres very thick­ly, as it were dartings of rays. Fig. 11. plainly shews all these.

Concerning these, in the first place, it shall be inquire into in general, For what end so many nervous infoldings, with almost innumerable fibres and shoots, are di­stributed about the Mesentery and the Viscera of the Abdomen. For when in these parts the fibres and nervous shoots are carried on every side with so thick a series, that they are variously infolded with th [...]r manifold meeting, it may seem wonderful, if every one of these be destinated to some uses, and are not rather sprinkled here and there by chance, and as it were by the inconsiderate sporting of Nature. And indeed any one can scarce think, that so many Vessels should be prepared for the performing the offices of motion or sense in that place. For those Viscera, unless highly pulled and affected with a Convulsion, are sensible of little or nothing that we know of; and their motions are almost no other thing than obscure Vermiculations or light Corru­gations, so that for the effecting them there is required no greater preparation than for the slow progress of a Snail. Wherefore from hence it hath come into the mind of some, that a certain Juyce, and that perhaps nutritious, was dispensed by this mani­fold passage of the nervous Pipes: which sort of office however if assigned to these Fibres dispersed about the Mesentery, why should not the same office either of re­ceiving or of carrying of nourishment, be granted to those in like manner divaricated about the Lungs and the Praecordia, and especially about the rough Artery? But truly [Page 165]it is highly improbable, that a nutritious Juyce should be contained in the Coats of the Trachea or of the Bronchia, which the nerves may suck out; nor does it more clearly appear, why more nerves should be destinated for the carrying of the alible Juyce to these parts of the Abdomen, or those of the Breast, than is needful for the musculous stock. But in the mean time, though we deny, that the whole nutritious matter is carried this way and that way by those or the other nerves; yet we think; that within those nervous passages an humor doth perpetually abound, which may be for a Vehicle of the animal Spirits, and a Ferment for the nutritious matter: with which going with the nervous humor towards the Intestines and to the other sinks of the Body, it is likely, that the superfluous and excrementitious serosities do often slide down together, and so are carried out.

But it may be well thought, as to the Mesenterick Nerves, and Infoldings in which they are terminated, and the Fibres most thickly going out of these, that these diffe­rent manner of Vessels are first Chanels, then Storehouses, and lastly the last Emissa­ries of the animal Spirits. If it should be demanded, for what end so great plenty of Spirits should be designed for these ignobler parts; I say, that this is done for the performing the acts of Motion and Sense there, which are highly necessary for the preserving of life it self. For although local motion, which is always performed by the help of a Muscle, as of a Spring, is not convenient for the Viscera of the lower Belly; yet intestine motions are brought forth by them almost continually, and after many fashions: viz. for the subduing the Chyle, also for the separation of some parts and particles from others, both of that, and also of the bloody Liquor, and the protrusion of every one towards their designed bounds, the Fibres and nervous shoots reaching into the Membranes of the Viscera and the Coats of the Vessels, yea and into the textures of the Parenchyma, are variously drawn together, to wit, these are pul­led upwards, those downwards; sometimes many together, sometimes apart or suc­cessively, are wont to be drawn hither and thither. In truth, it is a sign of the in discontinued action of these Viscera, that as well in sleep, and perhaps more than in waking, the Culinary work of Nutrition is performed; and whilst the Organs of the other Faculties are at rest, there is no quiet granted to these: but that the Mesente­rick nerves perpetually grinding in the Mill, are always busied for the preparing the alible humor and the exporting the same towards all parts.

Moreover in these parts, to which the aforesaid Nerves belong, there is found an exquisite feeling no less than a motive Faculty; for whatsoever heterogeneous or hurt­ful thing, mixed with the Chyle or blood, is brought to any Viscera, presently the Spirits, inhabiting those parts, being warned of the evil, do greatly tumultuate as it were by entring into a Conspiracy, that what is hostile or troublesom they might shut out. But indeed, because the animal Spirits, flowing by the passage of the inter­costal nerve to the Intestines and Viscera akin to them, proceed from the Cerebel; therefore the businesses of either Faculty, to wit, both the sensitive and locomotive, forasmuch as they are performed the Brain unconsulted, and the animal scarce know­ing it, are not so openly taken notice of, and for that reason they are accounted of less than the spontaneous acts of the other parts.

But as to the manner it self or way of the oeconomy, whereby the animal Spirits, destinated to the Viscera of the lower Belly, are exercised, we affirm, That plenty of them flow into all the Mesentetick infoldings by the passage of the nerves sent from the intercostal pair; where being heaped up to a fulness, as it were in so many Store­houses or places of Receipt, they are kept to be distributed from thence into several parts, as occasion requires. But that the Spirits flow out of these infoldings, not through singular and larger branches, (as is done in the Muscles) but as it were by Troops of Fibres, into their proper tasks, the reason is, because here the business is performed otherwise than in the musculous stock. For where a Muicle is fixed to the part to be moved, its implanted Fibres perform the whole work of Contraction, or of the motive endeavour; but it suffices for the nerve still to convey new supple­ments of Spirits, and as occasion serves, the Instincts of the Motion to be performed: but in the Membranes and the Viscera, where Muscles are wanting, the nervous Fi­bres themselves most thickly implanted, and distributed as it were so many little ropes, almost into every part of the subject, perform the business of Traction or drawing by themselves and their own proper endeavour or force partly; and partly solicite or stir up into motion the Fibres implanted in the Viscera disposed after an uncertain order; which they determinate in their action, and moderate or govern [Page 166]them, as it were so many fingers laid upon the strings of a musical Instrument. For although the Membranes and the Viscera themselves are indued with some implanted Fibres; yet these are not, as it is in the Muscles, of one kind and position; but in the same part some are straight, and others oblique or crooked, these tend upwards, those downwards, and others are carried round; so that divers sorts of motions ought to be performed in the same Membrane or Inward, sometimes together, sometimes successively or by turns: wherefore distinct nerves are required, not only for the several series of Fibres, but for all the parts of the subject, to wit, which may stop here a motion begun in that place, and may begin another anew, or may unite one with another. Truly the motion which is performed in the musculous stock seems like the rude and more simple work of some Weaver, where the shuttle being always cast after the same manner, the Woof is laid under the Thread or Yarn: but the mo­tions of the Intestines and Viscera may be aptly compared to a Texture very much variegated or flourished, for the weaving of whose more artificial substance or making there is made use of many hands together, or of a Machine diversly turning about, and furnished with more than a thousand sorts of motions.

Concerning the many Mesenterick Nerves, and Shoots, and nervous Fibres which go out of them by bands, we must consider chiefly these two things: to wit, what may be the office of each of them for the stirring up of motion or sense, either of them, or both together in any part: then secondly, what the communication of either of them may be with other nerves, infoldings or bundles of nerves, by reason of which a Sympathy or consent of actions arises at once in divers parts. According to these two respects we will particularly weigh now the several nervous Vessels belonging to the Viscera of the lower Belly.

Therefore in the left side the supreme Mesenterick branch being presently forked like the figure of the Letter Y, contains in its upper shoot the Stomachical infolding, which is also the Splenetick, and in the other lower the Renal infolding or that be­longing to the Reins. Moreover, about the knot of division it sends forth some shoots to the greatest infolding of the Mesentery, Fig. 11. F. G. Hence a reason is plain, wherefore there happens such affinity between the Ventricle and the Spleen, and between the Mesentery and the Reins, so that the very often and familiar Symptom of Vomiting is both in Splenetick, Colical, and Nephritick people: because when a Convulsion is begun in any part or Inward, which the Mesenterick nerve respects, presently other parts, to which the infoldings or shoots of the same nerve belong, are drawn into consent.

From this lower infolding a little bundle of Nerves being carried towards the Sto­mach, inserts its Fibres partly in its bottom, and partly sends them to meet with other Fibres sent down from the nerve of the Stomach, Fig. 11. n. The reason of the former is, That whereas there are many Coats of the Ventricle, and divers series of Fibres are disposed in them, for the actuating all of which with a due influx of animal Spirits, the Stomachical nerves, derived from the wandring pair, are not sufficient; it was fit, that for the outward Court as it were or Precinct of this In­ward, to wit, for the outmost bottom of it, some forces of Spirits might be supplied from some strange Kingdom, to wit, from the aforesaid nervous infolding of the Abdomen. Instead of this, Spirits also may slide downwards from the same Stoma­chical branch through other Fibres sent down, and be sent into this Splenetick in­folding. Besides also it is observed, That the adventitious nerves aptly conspire with the former, being of the proper dominion of the Ventricle, and that either are not only inoculated within the confines of the Inward it self, but they run into mutual embraces without it, and as it were joyn hands together.

It seems plain, that the nervous Filaments being carried from the aforesaid infold­ing to the bottom of the Ventricle, may serve there for the performing the acts of Motion and Sensation: but it doth not so easily appear with what office the other handful of Fibres reaching out from hence into the Spleen is charged (Fig. 11. ζ.) because this Inward is said to be destitute wholly of every animal Faculty. When we did elsewhere inquire into the use of the Spleen, we thought good to affirm, That its office was to separate the dregs of the Blood and the acid-saline Particles, and whatsoever were of a more fixed nature, and to concoct them more being received into its own bosom, and to convert them into an acid Ferment; by which being again delivered to the blood through the Veins, a sharpness and an asperity, as also an active or fermentative virtue are gotten forits Latex. Wherefore the whole sub­stance [Page 167]of the Spleen consists of a texture of Fibres in the form of a net; to wit, that the Feculencies of the blood might be more plentifully received, and contained within its spongy cavities and thick passages. I say therefore, that for the fit preserving and dispensing of the Splenetick Ferment, besides the Arteries which carry matter, and the Veins which continually sup back some portion of the same fermented, there seems to be need of many nerves also, which both by pulling the fibrous texture of the Spleen, might cause the melancholick and dark Faces, laid up in it, to be shaken together, and so by defending it from putrefaction and coagulation, cause it to be imbued with an acid and fermentative nature; and also that those nerves may sometimes draw together and constrain the blood carrying Vessels, sometimes open and inlarge them; that as occasion serves, the Feculencies of the blood may be sometimes more plentiful­ly, sometimes more sparingly laid aside out of the Arteries into the Spleen; also that more or less of the Ferment, preserved in the Spleen, may be poured out on the blood according to the requirings of the Passions or of the natural Instinct. No Hy­pochondriack but doth abundantly perceive, that some Splenetick nerves do perform motions; for those great perturbations which are wont to be excited in the left side, as when sometimes Inflations, sometimes constrictions of the inward parts, and sometimes various concussions are perceived with a wandring pain running here and there, they are only Spasms or Convulsions or wrinklings t [...]ther, with which the nerves of the Spleen are ordinarily affected. Nor do its nerves, taken with a Convul­sion, stir up tumults only in the neighbourhood of the Spleen, but oftentimes fur­ther into the Heart it self, yea into the whole Body the effects of their inordinations are carried. I have known an Hypochondriack, who presently upon the Spleen being disturbed, seemed to have his Pracordia, being drawn downwards, to be cruelly prest and bound together; so that being very sad and dejected in his mind, also complaining of an exceeding great straitness and constriction of his Breast, he thought himself almost dead. The cause of which kind of distemper was without doubt, that when many Fibres going out of the Splenetick infolding are united with other Fibres sent from the farthest end of the wandring pair, it easily happens, that the former, being distempered with the Convulsion, do draw together and pull downwards their yoke-fellows, and by consequence the Trunk it self of the wandring pair, from which the nerves are sent into the Praecordia: certainly by the Sympraxis or joynt action of either kind of the aforesaid nerves, viz. whereof these respect the Spleen, those the Praecordia, it is effected, that the Trembling, Oppression, and other grievous Distem­pers of the Heart, as also of the Spleen, so ordinarily happen. Further, forasmuch as the Fermentation of the blood depends on the Spleen, according to the influence of this, that performs its Circulation, sometimes pleasantly, sometimes disturbedly. Whilst the Spleen is at quiet, and free from any perturbation, the blood also is quietly moved in Hypochondriacal persons; but if the same be moved and exercised, (as it is wont to be in any passion or violent motion of the Body, or by a Medicine) presently its nerves being distempered with a Convulsion, shake it more with reite­rated contractions; so that the fermentative Feculencies, being shaken out of its bosom, flow back more plentifully into the blood, which cause its Latex presently to be troubled, and as it were muddy, and sharpen it with so great acrimony and mordacity, that it burns and pricks the Brain and Heart like needles; from whence in Splenetick people, besides that the Reason is obscured, the affections of the Mind, especially Sadness, Hatred, and Anger are very much increased.

Concerning the Splenetick Nerves, by another conjecture, we are yet brought to believe, that they, besides the exercise of the motive Faculty, do both instil into the Spleen its own humor, which promotes the fermentative virtue of that Inward; and also (because the nerves, as was shewn already, convey the Spirits, and sometimes the humors by either way, viz. forward and backward) the same implanted in the Spleen, do often imbibe from it an acetous or Vinegar-like humor, and as it were Vitriolick, from whose acrimony and notable twitching, they are forced into Con­vulsions.

But forasmuch as the nervous Infolding respecting the Spleen, communicates more nearly with the Ventricle, Mesentery, Liver, and Kidneys, and more remotely with the Praecordia and other parts placed at a distance; from hence the cause is plain, where­fore not only these several Viscera and parts, by reason of the fault of the Spleen, are folded together; but also on the contrary, why the Spleen being indisposed by any Disease, or trouble raised up in any of those parts, is wont to be disturbed: so it is [Page 168]not altogether for nothing, that the Symptoms every where infesting, the cause of them being unknown, are ascribed ordinarily to the Spleen; because it fixes not only its own inordinations in other parts, but also suffers for their peculiar faults: which notwith­standing is wrongfully ascribed to Vapours transmitted from this or that part, when the formal reason of every Distemper of this kind for the most part consists in the com­munication made through the Nerves.

The lower Infolding of the left side seems to be made for the Kidney placed near, into which chiefly the bundle of its Fibres is carried, Fig. 11. ♃. Υ. Υ. Certainly that these nerves, following the emulgent Vessels, do embrace the same, and bind them about with a various and frequent complication; that is so made for that end, that by reason of the Artery being so strained and frequently shaken by the drawings of the nerves, the Serum may the more easily be precipitated from the blood: wherefore it is observed in very great difficulty or danger, when the mind and all the nerves are strained for fear, that a frequent and more plentiful making of water, and that often painful, is wont to be provoked.

The Renal Infolding receives, besides the Nerve common to it with the upper in­folding, another new and peculiar one from the intercostal nerve, or rather that co­ming between from the spinal Marrow, Fig. 11. β. Hence it is, that the Loyns have a great consent with [...] Reins, and suffer so ordinarily for their Distempers with a grievous and largely diffusive pain. Forasmuch as this infolding communicates with the greatest of the Mesentery, the Colick distemper and the Nephritick are much akin, and it is often difficult to distinguish their fits one from the other.

The Mesenterick branch in the right side, as well as the left, being forked, con­tains two infoldings: the upper of these (which we call the Hepatick) sends forth from it self many little bundles of nervous Fibres; the greatest of which being car­ried towards the Liver, cloaths the Hepatick Artery as it were with a Net made of Fibres, Fig. 11. ♂. o. The most Learned Glisson observes, That the Hepatick Artery is bestowed on the Trunks of the Vessels, to wit, of the common Chest, of the bilary Pore, and of the Vena Porta; for the watering of which, and for the actuating them with heat and nourishing Juyce, it carries the arterious Blood; to which notwith­standing for the recarrying, an associate Vein is wholly wanting: wherefore that ought to carry the blood, not with a full and free influx, but by little and little, and always in a constant measure to those membranaceous parts: for otherwise there had been danger, lest from the bloody Latex plentifully rushing forward, for that it could not be still remanded presently through the Veins, an Inflammation should be excited, or lest from its torrent being transfused beyond its banks, the courses of the other rivers in the Liver should be disturbed. But for that the nerves, like Reins, do bind about the Trunk of the Artery, the inflowing of the blood it self is moderated, and they cause it variously to be dispensed according to the wants of those parts to which it is destinated.

From the Troop of Nerves going out towards the Liver, some bend down into the Pancreas, and others into the Cholidock Vessels, Duodenum, and Pylorus, and sow into them thick series of shoots, Fig. 11. π. π. The office of these seems to be, to pull together the excretory passages of those parts, and to shake them for the causing Evacuations of the boiling or turging humors upon occasion. Further, from these Fibres being carried upwards, when many others sent from either Stomachical nerve are united, the reason is plain, why from an hawling or pulling made about the Ventricle, the yellow Bile is drawn out of the Gall-chest into the Duodenum, which being carried from thence into the Ventricle, by reason of a Convulsion of that same Intestine, is cast up by Vomit: because the Stomachical nerves being irritated by a Medicine, or by any troublesom thing, for the making an Evacuation above, and for that cause drawn from thence upwards, they draw together the nerves belonging to the Liver and the Cholidock Vessels, for that they are tied to them, and bring them into consent with the superior Spasm or Convulsion. Hence it happens, that not only the Stomach being first tired, draws to it self the Bile by its Convulsion, and allures it into its own bosom; but the Bile also of its own accord growing turgid, and so being poured out into the Duodenum, forasmuch as it irritates the nerves of this Intestine, and then by their consent, provokes the nervous Vessels of the Ventricle, it presently induces a cholerick Vomiting.

The Hepatick Infolding communicates with the Splenetick by Fibres going between either, Fig. 11. θ. The reason of which seems to be, That when one infolding re­spects [Page 169]the end or the right extremity of the Ventricle, and another the left; that a consent in either and a joynt action may be made towards the Stomach, both com­municate between themselves by nerves, as if Internuntii. Truly it seems to come to pass by the passage of these nerves, that the Hypochondriacal pains oftentimes run from the left side into the right; to wit, for that a Spasm or Convulsion begun in the Sple­netick infolding, is wont to be carried to the Hepatick.

Between the Hepatick Infolding and the greatest of the Mesentery, many Fibres reaching out by bands, are cast out in the midst, Fig. 11. p. p. the office of which is to sustain a certain commerce and Sympathy; to wit, such an one is required, both that the Chyle may be ministred from the Intestines towards the Liver still in due proportion, also that the Bible may opportunely slide out from the Gall-bladder into the Intestines for the provoking of Excretion. For we are of this Opinion, That the Meseraick Veins sucking out a certain portion of the Chyle from the Intestines, immediately transfer it through the region of the Liver into the Vena Cava, whereby the blood in the ascending Trunk of the hollow Vein or Vena Cava, might be freshly imbued with nourishing Juyce; even as in its descending Trunk it is refreshed, the same being poured out through the Thoracical Vessels or those belong­ing to the Thorax. Wherefore it is needful, that there should be a very strict affinity between these Viscera; and the rather, because the Bile ought to be poured out from the Gall chest to the Intestines, not continually, but for some uses, by occasions and intervals. For the Nerves knowing best the wants of either part, warn them both of their mutual duty, and as occasion serves, stir them into action.

It is observed, That in the right side an ample Nerve is stretched out between the Hepatick and Renal infolding, Fig. 11. μ. So that between these infoldings a greater and more immediate consent is had, than between those pairs of the other side. The reason of which doth not easily appear, unless perhaps it should be so made for this end, that when from the Reins, in making of water, there is an endeavour of the serous Excretion, the Pylorus and the Cholidock Vessels being at once drawn down­wards, a protrusion of the Chyle and Faeces might be provoked towards the lower parts of the Belly. Certainly this connexion of these infoldings is chiefly the cause, why oftentimes most cruel Vomiting uses to come upon a Fit of the Stone; and that from such a Vomiting the Cholidock Vessels are very much emptied, as if provoked by taking an Emetick.

The greatest Infolding of the Mesentery being placed in the midst of the rest, like the Sun, disperses every where round about nervous Fibres like rays, Fig. 11. ☉. and casts them not only on every one of those infoldings, as if so many Planets with a peculiar Aspect, or Actinobolism or Irradiation, but also it distributes them into ma­ny Intestines, sanguiferous Vessels, and other parts lying round about: without doubt upon these nervous Filaments, which are carried from this infolding to the Intestines, as Lines from the Centre to the Circumference, every action of the Intestines, and espe­cially the Peristaltick motion of the Vermiculation, depends; namely for that these Fibres do move successively, and still move further every begun action, as it were with a spiral or Screw-like progress.

That from this Infolding many Fibres and shoots going forth, are inserted into the Trunk of the Aorta nigh its descending, and that these reaching towards the Inte­stines, accompany the Blood carrying Vessels, and in several places climb over them; from hence it may be inferred, That nerves also in the Abdomen are like Bridles and Reins cast on the sanguiferous Vessels, which either by straining or pulling them to­gether, may sometimes retard, sometimes incite the course of the blood according to the needs of the lower Viscera.

From the greatest Infolding of the Mesentery some noted Fibres and shoots are sent out into the Glandula's of the Womb or the Womens Testicles, Fig. 11. τ. τ. Into which also other shoots from the Trunk of the intercostal Nerve, ibid. v.v. and others going out of the nerve which comes between this infolding and the lowest of the Ab­domen, do come together, ibid. ψ. ψ. So that a provision of Spirits is carried into those parts from a threefold Store-house; which indeed is much larger than is done in the other Sex, when we find scarce any nerve to belong to mens Testicles. Indeed the Womb, besides that it is a very sensible part, ought also to be moved diversly, and in bringing forth a child very strongly: wherefore there are granted to this both more strong implanted Fibres, and also Nerves of a various kind and original.

Most of the Infoldings of the Abdomen, but especially the lowest, and that re­lated [Page 170]to it the greatest of the Mesentery, are oftentimes affected in the Passions com­monly called Hysterical, as shall be presently declared. Therefore if at any time such distempers proceed from the Womb, the cause is manifest wherefore the aforesaid infoldings are drawn into consent. But we have elsewhere shewn, That those Pas­fions are merely convulsive, and not seldom excited without any fault in the Womb. Further, that Symptom very frequent in those kind of Fits, to wit, in which as it were a Globe is perceived to be carried from the bottom of the Belly, and about the Navel to leap out impetuously, which therefore is thought to be an ascent of the Womb; I say, that it is nothing else than most cruel Convulsions of these infold­ings. Indeed oftentimes in Women, and sometimes also in Men, I have known when the convulsive Affection hath invaded, that a bulk in the Hypogastrium hath been seen to arise, then about the midst of the Abdomen so great a swelling to follow, that it could not be hindred or prest down, though strongly attempted by the hands of a strong man. Without doubt, the cause of this admirable distemper is, that within the nerves of the intercostal pair the inflowing animal Spirits, as often as they begin disorders or convulsive motions, first (as it is wont to be) begin to grow hot or to be exploded about the extremities of the nerve, to wit, in the lowest infolding of the Abdomen; which affection of theirs, when creeping upwards it is carried to the greatest infolding of the Mesentery, so that the Spirits inhabiting it are taken with the like inordination, it is no wonder, if that swelling up of the middle of the Ab­domen, and as it were an explosion of a certain nitrosulphureous matter, should be stirred up. For truly it is not probable, that that Symptom should be excited from the Womb ascending and being removed from its place, because, besides this part being fixed in its place and firmly established with Ligaments, the bulk of it also in Virgins is so small, scarce exceeding the bigness of a Walnut, that although it should be carried up into the Belly, it could not produce such a swelling. Not is it more likely, that this sort of distemper is stirred up from the Muscles of the Abdomen taken with a Convulsion: for they, however convulsive, draw together themselves and subject­ed parts upwards or downwards, or of one side, but they are not able by any means to bear themselves alost, and to lift up on high, with a force, the region of the Navel. But, as we suppose, the animal Spirits in the greatest infolding of the Mesentery growing fierce, and becoming apt to be exploded, (as such indeed they are whenever they enter into convulsive motions) they being there gathered round thickly into a Globe, do mainly blow up and lift on high with their effervescency and notable rare­faction that infolding with its whole neighbourhood, and at once drive upward the Viscera lying upon it with a certain vibration or shaking. A more full explication of this Symptom belongs to the Pathology of the Brain and Nerves.

In the mean time we shall take notice, that another certain Distemper, viz. the Colical grief doth belong to the infoldings of the Abdomen, and especially to this great­est of the Mesentery. For it may be thought, that the most cruel torments that are wont to be excited in this disease do come, not from an excrementitions matter shut up in the cavities of the Intestines, nor always from a sharp humor impacted in their Coats, but oftner from the nervous Juyce imbued with a certain acrimony, and stagnating within this infolding; from whence, by reason of a consent of this with the infoldings both Hepatick and Splenetick, a frequent and cruel Vomiting comes upon these pains. But these Pathologick Speculations being referred to their places, we will follow what we first of all instituted, the further passage of the intercostal Nerve, by which we are led to the two lesser and lowest Infoldings of the Abdomen.

Below the Mesenterick Nerves, out of which the superior Infoldings are made, ei­ther descending intercostal Trunk sends forth three or four singular shoots, which are carried into the Ureters, Fig. 11. v.v. The use of these seems to be, to pull to­gether, and to jog or shake those urinary Chanels, that the Serum separated in the Reins, may be the more readily drawn out towards the Bladder. Moreover, if at any time a viscous or muddy matter doth stick to the passages of the Ureters, or a more fixed stone doth obstruct their Cavities, they, by the help of the Nerves in­serted here and there in their whole tract, being pulled together and wrinkled, may press down and always move for ward any bulk or substance staying in the passage.

Nigh the Vertebra, out of which the Crural Nerves begin to go forward, three distinct branches brought to either intercostal Nerve, are carried from thence into the lowest hollowness of the Belly, where they make the infolding which is the lowest of the Abdomen, Fig. 11. ☽ φ. φ. φ. That here so many nerves, to wit, six large ones [Page 171]joyning together do make but a small infolding, viz. a lesser than is raised higher in a single branch of the nerve; the reason is, because this infolding is like an Inn, where the inflowing Spirits dwell no long time, but it receiving them only in their passage, presently commits them to other infoldings placed here and there above, below, and of one side, and made for divers offices; for from hence the chief passage, and as it were a broad way, leads to the greatest infolding of the Mesentery; moreover, from hence nerves, diversly going out, make three other infoldings, which respect the parts and ways by which the several Excretions, to wit, of the Dung, Urine, and Seed, are made in the lower Belly.

The first Nerve therefore sent out of this lowest Infolding into the greatest of the Mesentery, a little before it reaches to it, imparts two noted shoots to the Glandula's of the Womb; but in its ascent it admits four other branches, as it were subsidiary, viz. two on either side from the intercostal pair, Fig. 11. χ. so that the nerve here seems to be the chief means of passage of the animal Spirits destinated to the greatest infolding of the Mesentery and to the uterine Glandula's; which passage however is carried into the designed parts, not immediately, but a compass being made, it first goes forward beyond its bound, and at length with a certain going back. The reason of which is, that the motions of all the Intestines, viz. the Vermiculations should be directed downwards towards the straight Intestine, and also that the actions of the Womb should tend thither; therefore 'twas fit, that the animal Spirits should be sup­plied from below whither the motion inclined. For by the like means, this Mesen­terick nerve and the two returning nerves, being first carried lower, ascend into their Provinces; to wit, that they may pull together the respective parts toward that bound placed below, as it were to a Pully.

Further, for this end, to wit, that the influence of the Spirits actuating some In­testines, might be derived lower; the other infolding of the Abdomen, to wit, the least, is added immediately to this. Because upon the Nerves being carried from hence about an inch, there grows a small infolding; out of which, one nerve being sent out into the greatest infolding of the Mesentery, stretches it self under the top of the straight Intestine and part of the Colon, Fig. 11. ☿. α. And another nerve, descend­ing from this infolding, is carried under the lowest part of the same straight Intestine, Fig. 11. b. which also, two shoots carried from the infoldings placed in the Pelvis or Bason, meet, Fig. 11. d. d. It will not be hard to declare the uses of this infolding and its nerves: because all those nervous passages are emptied about the offices and motions of the straight Intestine. The ascending nerve directs the Vermiculations of the same straight Intestine, as also of the lower part of the Colon, and then (the greatest infolding of the Mesentery mediating) of some other Intestines to be made downwards; but the descending nerve, in opposition to the other, drawing the lowest part of the straight Intestine upwards, takes care that the Excrements being carried towards the Arse-hole, may not slide out suddenly and unexpectedly. Then forasmuch as two nerves from the two infoldings placed within the Bason or Tunnel, (which in­foldings immediately admitting a noted Vertebral branch, are partakers of the spon­taneous Function) meet with this descending nerve, and are ingraffed into it; it comes to pass from all of them together, that the Excrements being detained at the doors, when it shall be convenient, the Appetite commanding, are cast out. Nature, that it might shun filthiness, is so careful, that for the carrying out of the Excrements it constitutes nervous Vessels, with as noted a provision, as for the performing any where of the most splendid offices.

From the lowest Infolding of the Abdomen, two nerves being sent into the Tunnel, receive there on both sides a noted Vertebral Nerve; and so constitute two infoldings, to wit, one in either side, Fig. 11. C.C. K.K. These infoldings near the doors, pla­ced before the chief excretory passages, serve for the opening and shutting them: a Vertebral branch comes to either as a supply; by which it comes to pass, that be­sides the increasing the forces of the Spirits, their acts flowing from these infoldings, become in some measure spontaneous. By what means and for what end, the nerve ascending from either infolding, is bestowed on the straight Intestine, was shewn but now. Moreover, two descending on both sides, are carried into the neck or porch of the Womb, Fig. 11. e.g. Without doubt, whatever of sense or motion is made about the Venereal acts, is owed to the influence of the Spirits through these Nerves. In Men the delightful profusion of the Genital humor, and in Women the no less pleasant reception of the same depends on the action of those nerves. Lastly, [Page 172]from the same infolding another nerve descending and broken into certain shoots, is distributed on both sides into the Bladder and its Sphincter, Fig. 11. f. Certainly by these nerves the business of making water is performed, and when at any time the same is painful, the troublesom sense is impressed on them. But forasmuch as the nerves dedicated to the several Excretions proceed on both sides from the same infolding, therefore the acts of them all are in some measure alike among themselves, so indeed, that if any excretory passage should be weak or ill affected, it sends forth its charge which it should keep, whether it will or no. This is so well known, that there is no need to illustrate the matter with instances.

These Nerves and Infoldings being so made, there is not much business besides left for the intercostal pair. About the beginning of the Os Sacrum, both Trunks in­clining mutually one to the other, communicate among themselves by a cross shoot or two, then they end in very small Fibres, which are distributed into the Sphincter of the Anus, Fig. 11. q. r. s. Here the intercoast pair is after the same manner, as we have observed concerning the wandring pair; to wit, either nerve being brought to the end of its course, before they enter upon their last task, incline themselves to mutual embraces. Concerning the last offices of either pair, this Conformity may be also noted; that whenas the Viscera dedicated to Chylification, to wit, the Ventricle and Intestines, are still continued to the last by the same passage and the same perpe­tual cavity or hollowness; the first doors of this Cavity, to wit, the Orifices of the Ventricle, are kept by the lowest branches of the wandring pair joyned among them­selves; but before the last door of the same, to wit, the Sphincter of the Anus, the extremities of the intercostal pair, also before joyned among themselves, are placed. But to this part, as if it had never provided enough for it, besides the nerves sent hither from either infolding next above, and these extreme productions of the inter­costal pair bestowed on it, a branch also and certain fibres from the Vertebral nerve are inserted, Fig. 11. i. k. By the access of which it comes to pass, that the shutting and opening of this door-keeping Muscle becomes spontaneous. Truly many nerves, and those of a diverse kind, are distributed into the Sphincter of the Anus, to wit, be­cause the nutritious Juyce and its stinking recrements, like a certain Chymical mat­ter, are digested within the Intestines, as it were within a Matrace; therefore Na­ture, which best understands Chymistry, is very careful about the well-stopping the mouths of the Vessels.

From the same Nerve, viz. the last Vertebral, out of which a branch disperses fibres into the Sphincter of the Anus, two other Nerves proceed, which are carried into the Yard, Fig. 11. l. m. The greater of these, which is very large and long, is distributed into the nervous Body of it; the other lesser, into its Muscles. This mem­ber, because it receives nerves only from the spinal Marrow, according to our Hypo­thesis, ought to swell up and to be moved only at the spontaneous pleasure of the will: but that oftentimes, by reason of the swelling up of the Genital seed or humor, it is erected and blown up with Spirit, whether one will or no, that is caused chiefly for this reason, Because from this Vertebral pair, from whence the nerves of the Yard arise, a nervous process is stretched out into the Vertebral pair next above it: in which the infolding, placed in the Tunnel, imparting nerves to the Prostatae, is radicated, Fig. 11. I. K. into which infolding also a noted nerve from the intercostal pair is im­planted. When therefore a communication is had between the Prostatae, which de­pend much on the intercostal Nerves and the Yard, (by reason of the roots of either being joyned together by the nervous process) it comes to pass, that the action of this follows the affection of those parts: but those parts, viz. the Prostatae, are apt to be moved not only by the turgescency of the Seed, but also by the passage of the intercostal Nerve are wont to be irritated with too unseasonable an action, according to the impressions made by the Senses or the Brain; into the consent of which pre­sently the Yard is excited.

Concerning the Nerves which belong to the Testicles, here is not much to be spo­ken; for we have often sought in vain for a great company of nervous passages in them: I have very diligently searched sometimes in Man, also in a Fox, Dog, Calf, and likewise in a Boar and Monkey, but could never find belonging to them but one nerve carried from the Vertebral pair, which also for the most part is bestowed on the Cremasteral Muscle, Fig. 11. M. so that, although an excellent humor is pre­pared within those parts, yet it doth not easily appear, that its matter is derived thi­ther through the nerves; for we think the Genital humor is no more dispensed by [Page 173]the nerves than the nutritious. For truly it seems, that the Arteries instil a spiri­tuous liquor into the Testicles after the same manner as in the Brain; wherefore in their neighbourhood these sanguiferous Vessels being very much divaricated or spread abroad, are turned about into little serpentine chanels, whereby they subtilize the humor destinated to the Testicles, and insinnate it, having put off all thickness and Feculency, and being truly sublimated, into their substance; because there, as within the Cortex of the Brain, the spirituous liquor being imbued with a volatile Salt im­planted in the part, passes into the most noble Clyssus, viz. the Genital humor. But here is not a place to discourse more largely of the nature and origine of the Seed: yet because it is commonly objected, That the Seed is made of the nervous Juyce and plenty of Spirits fetched from the Brain, and therefore a large expence of it doth induce quickly on the Brain and Nerves a great debility and enervation; I say, this comes to pass, because after great profusions of the Seed, for the restauration of the same humor, (of which Nature is more solicitous than for the benefit of the individual) presently greater Tributes of the spirituous Liquor are required from the blood to be laid up into the Testicles: wherefore the Brain is made languid, being defrauded of its due stock and afflux of the same spirituous liquor; and the Spirits influencing it and the nervous System, because they are deficient in the Fountain it self, are very much depauperated and become flagging. Besides we may add, That the animal Spi­rits also which actuate the Prostatae coming from the spinal Marrow, are consumed about the Venereal acts very much; so that the Loyns are also enervated for this reason.

CHAP. XXVIII.

AFter we have unfolded the Nerves of the wandring and intercostal pair, which being Executers of the involuntary Function, are stretched out to the Prae­cordia and all the Viscera of the middle and lower Belly, and also to some other parts: Next to these follow some other Nerves communicating with the afore­said in their beginning, or in the exercise of the same office, viz. the spinal Nerve and the Nerve of the Diaphragma; of which we will speak in order.

We have already shewn, that the Nerve of the wandring pair in the beginning is made up of numerous Fibres: to which is joyned another noted Nerve arising from afar, and being ingraffed with them, goes forth together with them out of the Skull. Concer­ning this Nerve, because the beginning and distribution of it being very irregular, have not as yet been noted by other Anatomists, it may seem worth our labour to make a little more diligent inquiry. Therefore if we would search into the beginning of this nerve, that is found beginning with a sharp point in the side of the spinal Marrow nigh the sixth or seventh Vertebra of the Neck, Fig. 12. C. C. But being increased in its ascent, is no where inserted into the medullar Trunk, but in its whole tract on both sides leans on its side, to which it is knit by certain admitted Fibres towards the superficies. This arising up from the Neck after this manner, and being carried with­in the Skull, is joyned to the Fibres of the wandring pair, and is ingraffed with them seeming to grow together into one Trunk, and goes out with them at the same hole from the Skull; which being passed through, the spinal Nerve presently departing from the Trunk of the wandring pair, is at length reflected outward, Fig. 9. ♀. ♂. This stranger or travelling nerve after a short commerce having left his companion, is carried upon the Muscles of the Neck, to which it imparts some shoots, and is inoculated with a certain shoot of the tenth pair; but from thence being carried on further, it goes alone by a long passage, till it comes to the Scapular Muscle, on which it is almost wholly bestowed, Fig. 9. ☽. This nerve is found constantly, not only in Man and four-footed Beasts, but also in Fowls and Fishes; and in these it seems to be destinated instead of Arms, and for the moving of their wings and fins.

Concerning the use of this Nerve, and the reason of its irregular beginning, we [Page 174]shall conjecture after this manner: Forasmuch as that is destinated for the perform­ing the motions of the Muscles belonging to the Arms and Neck, therefore it ought to arise out of the spinal Marrow: but that it is not carried by a direct and near way into its Province, but being carried about by a long compass before it enters upon its task, communicates in its beginning with the nerve of the wandring pair; certainly this seems to be done, to the end that this Spinal nerve, being carried into the parts of the wandring pair, might perform the acts of the Function only involuntary. And indeed it may be observed, That besides the spontaneous motions wherewith the Neck and Arms are wont to be imployed with the previous intention of doing this or that thing, those parts also, before any other member, are affected with pathetick and sudden motions, according to the force of the Passions, the animal not being conscious of it. For almost all living Creatures do not only turn about their necks at any noise to behold whatever might cause fear; but they being any ways affright­ed in the twinkling of an eye fly away, their feet, wings, fins, or other part an­swerable to them, being set into a rapid motion. The Neck and the Arms are pliable or observant, not only to fear, but in like manner to the other Passions. For brute Animals, as well as Man, being puffed up with pride or anger, (as we have elsewhere intimated) have their Necks swollen, and their Crests lifted up: But as to Man, his hands and arms are so obsequious to the Passions, and almost to all the conceptions of the Brain, that they are continually agitated in the doing of any other thing with various gestures, whereof we are ignorant or not willing them: we scarce­ly think or speak any thing but at the same time the hands are flung out here and there; and whilst the Tongue hesitates or sticks, or the words at it were stick between the Jaws, the right hand is exercised, as if by its gesture it were endeavouring to draw out more swiftly the sence of the mind. Truly that these parts, to wit, the Hands and Arms, do so nearly conspire with the Affections of the Brain and Heart in their motions in some measure in all living Creatures, but more eminently in Man, the cause seems to be this nerve's coming from the spinal Marrow to the beginning of the wandring pair, and communicating with its nerves, and receiving from them as it were the note or private mark of the involuntary Function.

So much for the spinal Nerve, which also like a shrub, growing from other snrubs, hath no peculiar origine, but having received various fibres, is radicated for the greatest part in the spinal Marrow, and (as hath been shewn) partly in the nerve of the wandring pair. Concerning the nerve of the Diaphragma, (of which we shall speak next) many things occur no less worthy remarking. As to its beginning, it may be observed, That it arises from the brachial nerves with a double or triple root; to wit, two or three shoots going out of the aforesaid nerves, grow together into the same Trunk, which is the nerve of the Diaphragma. In man its first shoot, which is also the greatest, is produced out of the second Vertebral nerve; and when the first brachial nerve arises from the same handful of Vertebral nerves going out at this place, the aforesaid shoot is rooted in its origine: wherefore, when in Brutes the first brachial nerve arises from the fourth or fifth Vertebral, the nerve of the Dia­phragma also begins its rise far lower: two other shoots arise out of the same stocks of the brachial nerves which follow next, Fig. 9. Y. γ. φ. But the Trunk which is made out of these shoots goes forward single through the passage of the Neck and the cavity of the Thorax without any branching forth, even to the Diaphragma, Fig. 9 χ. where being at last stretched out into three or four shoots, it is inserted on either side to the fleshy or musculous part of it: so that, because the Diaphragma is a Muscle, and per­forms both its motions, to wit, Systole and Diastole by its own Fibres, the office of either nerve is only to carry bands or forces of animal Spirits requisite for the indis­continued action of that part, and also to convey thither the Instincts of the Motions variously to be performed.

As to the first use of this Nerve, viz. for the passage of the animal Spirits, the business is performed in this Muscle, as it is in the Heart. The Spirits flowing into the Diaphragma by the nerves, receive subsidiary Forces, to wit, a sulphureous Co­pula from the blood, upon whose explosion being still iterated by turns, and the re­ceiving of new, the action of this perpetual moveable depends. Concerning the In­stincts of the Motions transmitted by the passage of this double nerve, we may ob­serve, That they are, especially in man, of a double kind: viz. either the action of the Diaphragma merely natural for the performing of Respiration, is continually re­ciprocated according to the uses of the Heart and Lungs, and altered many ways in [Page 175]their tenour according to their needs, or secondly, a certain irregular and unusual motion of the Diaphragma is wont to be excited at the beck of the Appetite, or from the instigations of other parts; for the which, whilst the rest of the Organs of Re­spiration are compelled to conspire, the act it self of Respiration becomes after a va­rious manner interrupted or unequal.

1. As to the first of these, viz. the unforced motion of this Muscle, it may be ob­served, That the Diaphragma, with the Muscles of the Thorax and the parts of either, conspire in their motion with the action of the Lungs and Heart: and that between all these such a joynt action may be sustained, it is observed, That three or four bran­ches are sent out from the Vertebral nerves, in the branches of which the nerve of the Diaphragma is rooted, into the intercostal infolding, Fig. 9. Θ. and whereas from this infolding the nerves are carried into the Muscles of the Thorax, by this means a com­munication and consent of action is effected between these and the Diaphragma. There­fore the Diaphragma drawing with it self the Muscles of the Thorax, by reason of other nerves, conspires with the Praecordia. These in man going from the intercostal nerve, are already described; and in Brutes from the lower infolding of the wandring pair a nerve is sent down into the infolding of the Thorax, to which besides so many shoots and certain fibres reaching forth into the nerve of the Diaphragma, are instead of such a commerce.

2. The Anomal and irregular motions of the Diaphragma proceed from various causes and from the divers instigation of other parts, which also in man become much more signal than in brute Animals; because in him the communication is notable by the nerves reaching out from the Cervical infolding of the intercostal pair into the nerve of the Diaphragma; which kind of infolding and nerves are wanting in Brutes.

As to the Species themselves of irregular motions into which the motion of the Diaphragma is wont to be perverted, it may be observed, That we are able at our pleasure to stop breathing or respiration for some space, and presently to take it or draw it out. In laughing, weeping, and singing sometimes the Systole, sometimes the Diastole becomes stronger, and is made frequenter upward or downward with a repeated shaking; which sort of actions of it are made by reason of those near com­merces had between the nerve of the Diaphragma and other respective parts of the Breast and Face: yea indeed from hence it is effected, (as we have already shewn) that man is peculiarly a laughing Creature. Further, (which we have shewn else­where) from the Sympathy which happens between the parts of the Mouth and Face with the Diaphragma by those nerves, a good reason of sneezing may be given, and that Problem of Aristotles easily solved, to wit, why men alone, or chiefly before other Creatures, sneeze: For the act of sneezing seems to be made for this end, that man may not only clear his Nose, but that all Torpor or heaviness may be shook off for him from the neighbouring Organs of the Senses, yea and from all the fore-part of the Brain: which thing easily succeeds, if the Membranes and nervous passages besmearing the Nostrils and the Sieve-like Bone, like the holes of a Sponge, being strongly wrung forth or squeezed together, be forced to shed forth their moistures; for these parts so emptied, presently like a pressed Sponge, receive other humors, to wit, those coming from the neighbouring parts. In the mean time, that the watry heap so laid up about the caverns of the Nostrils, may be emptied, it ought to be carried away, or wiped out from thence by a vehement blowing of the Air or breath. Wherefore it is observed, That whilst the inward parts of the Nostrils being very sen­sible, begin to be wrinkled together from some sharp thing pulling or pricking them, and by that means to draw out the watry humor presently by reason of the passage from thence by the branches of the fifth pair into the intercostal Trunk, and from thence by the passage of the nerves which are extended from its Cervical infolding into the nerve of the Diaphragma, the consent of the same Action or Convulsion is produced even into the cross bound or Midriff; so that by the same Act as it were with which the Nostrils are wrinkled, the Diaphragma also with the Diastole being stronger and longer draw out, is depressed, that the Breast being dilated as much as may be, the Air may be the more copiously inspired. Then as soon as the Spasm or Convulsion of the Membranes, drawn together within the Nostrils and fore-part of the Head, begins to remit, presently the Midriff leaping back with a force, causes the inspired Air to be violently exploded or driven out, which strongly wipes away and carries forth with it the humor pressed out within the caverns of the Nostrils.

We yet ought to inquire concerning the Nerve of the Diaphragma, what is the reason, that it always proceeds from the Brachial nerves, and why it doth not rather arise immedisitely from the spinal Marrow. Truly from hence it seems to follow, that the motion of the Arms in some sort respects the action of the Diaphragma; or on the contrary, that this depends on that. Indeed between these two a certain respect or habitude happens; which easily appears by this Argument: The Arms or fore Legs in all Creatures are made for labour and hard exercise; because by the force of these men fight, and perform the most hard and laborious things, and Brutes run and ascend the most steep places with great pains. But it is very well known, that by too much labour and over vehement motion of body, the act of Respiration is very much increased, so that the breath almost fails, and is oftentimes in danger to be lost. The reason of this is, because by great exercise the blood is too much forced into the bosom of the Heart, which, lest it should suffocate it, that it might be emptied into the Lungs, very frequent and difficult Respiration is instituted. Therefore from hence may be inferred, That the exercises of the Body ought to be regulated according to the state of the Praecordia; or that the motion of the Arms should observe the action of the Diaphragma, viz. lest they being stirred by a violent motion, cause the blood to be driven more into the bosoms of the Heart, than the Diaphragma instituting a most fre­quent Respiration, can draw from thence into the Lungs. That this Rule may be perpetually observed of all living Creatures it is so provided, that the nerve of the Diaphragma, chiefly conducing to Respiration, should be tyed, as it were a bridle, to the Brachial nerves, which are the principal in the motion of the Body, and so might timely warn these, if unmindful of their duty, and as soon as breath fails, should command them to desist from further moving the Body. Wherefore we observe, when at any time labouring Cattle are urged beyond their strength in labour or mo­tion, oftentimes either some deadly hurt of the heart follows, or else some uncurable disease of the Diaphragma; for by such immoderate labour, either the Beast lan­guishing quickly dyes, when it is commonly said, that his heart is broke; or else the tone of the Diaphragma being wholly broken, Respiration ever after becomes painful and difficult: which is wont to happen ordinarily to Horses, who are driven into too rapid a course with a full Belly.

CHAP. XXIX.

THus far we have described all the Nerves stretching out to the Praecordia and Viscera, also to most of the other parts, which are the Organs o [...] the invo­luntary Function, according to the manner by which they are wrought in man; and we have shewn their Offices and Uses, and the Reasons of the most noted appearances in all. Before we proceed to the other Conjugations of the Nerves, it behoves us to shew with what difference the aforesaid Nerves are found in brute Beasts, and for what end such a difference is ordained.

It was already intimated, That the Trunk of the wandring pair in four footed Beasts doth send forth to the Heart and its Appendix more nervous Vessels than in Man. The reason of which is obvious; because the Cardiack nerves in Brutes pro­ceed almost only from this pair, and scarce at all from the intercostal; wherefore when they are only of one origination, therefore more are required, all which not­notwithstanding are much fewer than the same are in Man from a double stock, viz. being carried from both the Nerves: forasmuch as Beasts want prudence, and are not much obnoxious to various and divers Passions, therefore there was no need that the Spirits should be derived from the Head into the Praecordia by a double passage, [Page 177] viz. that one should be required for the exercise of the vital Function, and the other for the reciprocating impressions of the Affections; but that it may suffice, that all those destinated to every one of their offices, may be carried still in the same path.

In most Brutes the intercostal Nerve goes alone from the Ganglioform infolding of it almost without any branching to its infolding of the Thorax: in which passage how­ever it is not always after the same manner in all; for in some it is carried single and apart from the Trunk of the wandring pair, nor doth it communicate with it in its whole journey, unless a little higher by a shoot sent down from the Ganglioform in­folding: but in many the intercostal Nerve passes presently from its Ganglioform infolding into the neighbouring infolding of the wandring pair, Fig. 10. C. where, when both the nerves seem to close together, from thence both being involved under the same common inclosure, as it were one Trunk, they are carried together till it comes over against the first Rib, and there an infolding being made, the intercostal nerve, departing from the wandring pair, is carried into the infolding of the Thorax; and the other nerve also is stretched between this and that infolding: which nerves, when one is carried under the other above the Artery of the Chanel-bone, making as it were an handle, straiten its Trunk, Fig. 10. g.

Although the intercostal Nerve is carried from the Throat to the top of the Thorax under the same sheath with the Trunk of the wandring pair, yet it is not united to it; but they remain distinct still both of them in the whole tract, and the Membrane be­ing dissected, they easily separate one from the other, unless they be knit together by some fibrils sent from one another in some places: but forasmuch as by this means the intercostal nerve being joyned to the Trunk of the wandring pair, goes under its cover, it seems to be so made only for its safety and better passage: wherefore in some perhaps where the intercostal Trunk is greater, or the course of its passage shorter, where such a safeguard is not needful, it descends alone. We have seen this Nerve covered with the safeguard of the wandring pair of one side, and in the other to have gone out by it self alone.

Whether the intercostal Nerve departs from the lower Infolding of the wandring pair or not, however a branch is stretched out between this infolding and that of the Thorax in many, perhaps in all brute Beasts, which in its passage binds about the Vertebral Artery, whereby the Sympraxis or joynt Action between the Praecordia and the exterior Organs of Respiration is sustained: yea from this lower infolding of the wandring pair sometimes we have observed a shoot and fibres to be carried to the beginning of the Brachial branch, in which the nerve of the Diaphragma is rooted; also sometimes, though rarely, we have seen some shoots sent from the infolding of the Thorax towards the Heart and its Appendix. In a Monkey above this infolding of the Thorax, as we have intimated before, were some shoots and small branches reach­ing from the intercostal nerve towards the Praecordia.

We may take notice concerning those Nerves below the Praecordia, distributed eve­ry where into the Ventricle and the lower Viscera, that there is scarce any difference of them in Man and Beasts. The nerve of the Diaphragma is placed lower in four­footed beasts: the reason of which is, because the Brachial nerves, out of which that ought to proceed, arise lower; to wit, because Brutes have longer necks, as if destinated to the yoke. These things being thus premised concerning the difference of the Nerves in either Species, it remains that we pass on to the unfolding the re­maining pairs of them.

Therefore of those arising within the Skull, the ninth pair is made up of many Fibres also in its beginning, (as was shewed before) out of which being gathered to­gether one Trunk being made is carried towards the Tongue, through whose whole substance, to wit, from the bottom to the top, having passed, it disperses in its whole passage small shoots on either side, Fig. 9. [...]. So that nothing is more obvious than that this nerve performs the motions of the Tongue requisite for the articulation of Sounds, as the nerves of the fifth pair spread into this member, serve for the distin­guishing of Tastes; for the exercise of either Faculty, viz. both motive and sensitive, the texture of the Tongue being notedly fibrous, hath the virtue of a double Organ; therefore by the two nerves, besides the supplements of Spirits, are carried both the Instincts of the Motion and the sensible Impressions.

That the aforesaid Nerves of the ninth pair may more easily perform the mo­tions of the Tongue, it sends forth downwards one shoot before the entrance of the Tongue, which is united with a shoot from the tenth pair meeting it destinated to [Page 178]the Sternothyroeidal Muscle; and the other little branch of the ninth Conjugation is distributed into the Muscles of the Bone Hyoides, Fig. 9. Θ. ☉. In truth these shoots being sent down as so many little ropes, conduce to the moving of the Muscles, which are fixed to the bottom of the Tongue, which Muscles being placed as so many Props to the Tongue, do facilitate its motion.

The Nerve of the tenth pair, although it may seem to arise within the Skull with many little Fibres also, yet being sent down from thence into the bony Cloisters of the Spine, not arising but within the first and second Vertebrae, it is carried without. Pre­sently after its entrance it sends forth two nerves into the infolding of the interco­stal nerve; for what end hath been already shewn: But its chief Trunk spreading downwards, and receiving a shoot produced from the ninth pair, is bestowed on the Sternothyroeidal Muscle. Moreover, this nerve reflects branches outwards, which are distributed into the Muscles of the Neck reaching out towards the hinder part of the Head; so this pair, as if it were only of the number or rank of the Vertebral nerves, imparts some branches to the intercostal nerve, and all the other shoots and branches of it serve for the performing of the motions of the Muscles of the Neck, Fig. 9. H. *. ▭. Δ

So much for the Nerves arising within the Skull, which (as was shewn) having their being from the parts of the Brain or Cerebel, are destinated to the offices of the spontaneous or the involuntary Function, and are chiefly distributed into the Organs of the Senses or the Viscera of the vital and natural Faculty. There remain many other Conjugations of Nerves, the roots or beginnings of which consist in the spinal Marrow, which is only the exterior production of the oblong Marrow. These spinal Nerves, besides some branches that they bestow on the intercostal pair, are imployed almost wholly on the musculous stock, and the office of them is to carry outwardly the forces of the Spirits and the Instincts of the Motions to be performed, and to con­vey inwardly the impressions of sensible things. Forasmuch as the spinal Marrow seems to be derived from the Brain, and is as it were a broad and high road produced or leading from the same, without any paths or tracts inserted to it from the Cerebel, therefore the animal Spirits flowing within its nerves, do almost wholly execute the Acts of the spontaneous Function.

To describe all the several pairs of the spinal Nerves, and to rehearse all their branchings, and to unfold the uses and actions of them, would be a work of an im­mense labour and trouble: and as this Neurologie cannot be learned nor understood without an exact knowledge of the Muscles, we may justly here forbear entring upon its particular institution: but it may suffice concerning these nerves and their medullar beginning, that we advertise only in general what things may occur most notable and chiefly worth taking notice of.

As to the Nerves therefore produced out of the spinal Marrow, it may be observed, That in both sides of it, nigh the outward margine or brim, four or five Fibres arise in the superior brim, and as many in the inferior: either maniple or handful pass through with distinct Fibres the Pia Mater, or the lowest Coat of the spinal Marrow, which is as it were the common sheath of them all; but afterwards the Fibres passing through the third Membrane of either margine, (for three cloath the spinal Marrow) they joyn together, and having cloathed themselves with a Coat gotten from the se­cond Membrane, they become as it were one Trunk; which Trunk going out at the space between the knot of the Vertebrae, is again divided into many nerves destinated to several parts. After this manner in the whole tract of the spinal Marrow, the Vertebral nerves have their birth; but in those places where the Brachial and the Crural nerves go out, both the thickness and the breadth of the spinal Marrow are in­creased, and also the handfuls or bands of the Fibres are larger. All these are well represented in Fig. 12.

The Brachial Nerves are not only far greater than the Vertebrals, so that they ap­pear as it were large and broad nervous chords; but that they may conspire together, and serve for the strong motions of the Arms, or the fore Legs of Beasts, it is observed. That very many of them are knit together by the cross nervous Processes. These Processes in four-footed Beasts (the fore Legs of whom are destinated for unweariable pains and difficult lobour) are produced cross ways after a curious manner, as may be discerned, Fig. 10. l. l. The use of these seems to sustain not only the consent of action in many nerves together, but also their mutual strength; that some bands of Spirits might awaken or stir up others, and for the exercising strongly the locomo­tive [Page 179]force, they might mutually support and relieve one another. And not much unlike this, the business is about the Crural Nerves, where nervous cords signally large, being produced from the Junctures of the Vertebrae, whilst they descend to­wards the Thigh, they which are above receive in their whole tract the nervous Pro­cesses which are sent out still from those below, Fig. 11. p. p. p.

We may yet take notice farther concerning the spinal Marrow, that as it sends out Nerves by bands, and as it were by troops, in an orderly series and military order; so its sanguiferous Vessels are disposed with no less signal artifice. For those which are carried in the superficies of the spinal Marrow, and the Arteries, Veins, and other Sanguiducts, which are nigh its compass, do contain some things more rare and highly worth the noting.

In the first place we may observe, That the blood-carrying Vessels do cloath the whole substance or frame of the spinal Marrow, as well as the oblong Marrow with a thick series of shoots; which may be made more manifest to any one, if first of all Ink were injected into the Vertebral Artery; for from such an injection often repeated, it will easily appear, that the infoldings of the Vessels do cover as it were in the shape of a Net, the upper tract of the Marrow. But by what means these Vessels proceed on both sides from the Trunk of the Vertebral Artery, and also the blood-carrying Veins, which are destinated to the whole spinal Marrow, and the inferior portion of its arterious passages, doth not so plainly appear; because the bony Cloisters of the Vertebrae are not broken through without much labour, especially in grown up living Creatures; and in that work the beginnings and branchings out of very many Vessels are wont to be blotted out: But that we might more accurately search into these hid things, we made the Dissections of several Embryons, in which we were able to dissect the Vertebrae as yet soft, and to take out of them the Marrow whole, and to look more narrowly into all the recesses of the Bones: further, that all the tracts and bran­chings out of them might be the better perceived in all the Vessels, we did cast in divers coloured Liquors. And we had our desired wish: for presently we found with much admiration, that those kind of Vessels, viz. Arteries, Bosoms, and Veins, which respect the Head, belong also to the spinal Marrow with no less a noted dispo­sition of provision.

When we did dissect the Heads apart from the Spine, we did think, according to the Opinion of the Vulgar, that the Vertebral Arteries did belong only to the Head: and when there did appear in the cut off Trunk of the oblong Marrow three arterious branches (as they are described above in the first and second Table) therefore in the Explication of either Figure we have affirmed the Vertebral Artery to be carried with a triple branch into the hinder part of the Head. But the Vertebral Artery pays to the superior part of the Spine as great Tributes of Blood as to the Head it self; and that middle arterious branch, which is marked in the first Figure with the Letter T, in the second with S, doth not ascend into the Head, but descends from that con­course of Vertebral Arteries towards the Spine, and conveys downward from the common flowing together of the blood there made by many Arteries, the Latex for the watring the top of the spinal Marrow. Wherefore in this place it seems conve­nient, that we do not only correct that errour of ours, but that we deliver an exact Description of all the Vessels which are destinated to the Spine, viz. which contain many wonderful things. As therefore these Vessels are of a threefold kind, viz. Ar­teries, Bosoms, and Veins, we will expose each of them particularly; and first con­cerning the Arteries we say,

The Arteries which carry the Blood towards the Spine, are disposed after one manner above the Heart, and after another below it. As to the first, whereas the Trunk of the Aorta being there cleft presently into many branches, departs from the Region of the Spine, therefore the Vertebral Artery is produced on both sides from its axil­lary branches, which ascending straight into the hinder part of the Head, sends forth a branch into the meeting together of every Vertebra: But below the Heart, foras­much as the Aorta, in its whole descent, lyeth on the Spine, two Arteries are recei­ved into the Spine from its bottom nigh its Internodia or spaces between the knots of the Vertebra; so that if the Trunk of the Aorta be cut open long-ways, there will appear a series of double holes through its whole tract, after a most curious manner, as in the head of a Lamprey.

The arterious Branches which are carried both above and below the Heart towards the Spine, becoming presently forked, bestow one shoot on the neighbouring Muscles, [Page 180]and another they insert into the Junctures of the Vertebrae; which being carried with­in the bony Den, is cleft presently into three branches, two of which are bestowed on the medullar Trunk, and the other on the Membrane compassing about the bony Den before, Tab. 13. Fig. 3. a. b. c. d. e.

As to the shoots destinated to the medullar Trunk, they presently tending two ways, and meeting with either maniple or band of nervous Fibres, ascend towards their be­ginnings; and so one little Artery having got to the superficies of the hinder Marrow, distributes into it hairy Vessels: but the other arterious shoot, which is the greater and chiefest, as soon as it attains the margin of the former Marrow, is carried from thence by an oblique passage into the middle fissure or cleft of it, where meeting with a shoot of the pair of the other side, it is united to the same, and from that joyning together the arterious Trunk, as it were a common passage, and made up of either Vertebral shoot, descends into that cleft by the open space of one of the Vertebrae, and in that short passage both dispenses little Arteries on either side, and also inserts them leaning on the Pia Mater more deeply betwixt the sides of the Marrow: and so whereas in the whole tract of the Marrow, the chief Trunk of every Artery is carried into the middle cleft, it seems at first sight, as if the same arterious Trunk were carried under the whole substance of the Marrow from the head to the tail, Tab. 13. Fig. 1. Further, as by a concourse of several shoots of either side, the spinal Artery descends above the clest of the Marrow; so where the Trunks of the Vertebral Arteries joyn together (which happens to be done sometimes in the hinder part of the Head above the oblong Mar­row, and often in the Neck above the spinal) an arterious branch somewhat bigger than the rest is stretched out downwards. This formerly (as we mentioned but now) we mistook for the third ascending branch of the Vertebral Artery. But I have often taken notice, that in Brutes, where the Vertebral Arteries have met together with an acute Angle above the medullar Trunk, they are presently, departing one from another, stretched out directly to either brim of the Marrow, from whence imme­diately being bent back, they are carried again into a mutual meeting, so that be­tween their two joynings together is made the figure Rhomboides, as it is in Tab. 13. Fig. 1. C. The reason of which without doubt is this; to wit, that the more rapid course of the blood going towards the Head might be hindred by its flood being a little space divided.

The third Branch of either Vertebral Artery being carried into the anterior Ca­vity of the bony Den, and being presently made forked, tends to the right and left, and is on both sides inoculated to the next shoot of the same side and by the cross pro­cess, they of either side are united after the same manner; and so all the Arteries of this cense or rank receive one another mutually, as it were links of a chain, in the whole tract of the Spine, and are continued in the same bending passage. If Ink be cast into the Trunk of the Vertebral Artery and most of the hollownesses of the Aorta, all these Arteries, dyed with the same, will appear a pleasant spectacle, like Net-work, as may be seen Tab. 13. Fig. 3.

The top of this arterious Infolding being carried into the Skull, inserts two shoots sent forth straight into the wonderful Net, and imparts two others going out side­ways on both sides to the Dura Mater: the lower end of the same reaching to the Os Sacrum, ends in very small Vessels which serve for the Membrane of the Bones.

If it should be asked, For what end these Arteries being concatenated with such fre­quent ingraffings are disposed within the Back-bone: This seems to be so ordained for three uses: viz. First, These Vessels (as also the passages of the Bosoms) are divari­cated after this manner with repeated compassing about, that a constant heat from the blood being so turned about, as it were into frequent Whirlpools, might be sup­plied about the compass of the spinal Marrow, as it were by a Balneum Maria; even such a manner of office as the Choroeidal infolding performs within the infolding of the Brain. Secondly. Care is taken by this means, lest the blood destinated for the spinal Marrow, might flow thither too plentifully, or might be defective in its due influx; for the blood being about to flow into the medullar stock plentifully, is di­verted from the little branches c. d. into these Emissaries e. f. and in its defect the sub­sidiary provision being called out of the middle infolding through the chanel e. into the Vessels c. d. is derived into the same medullar Trunk. Thirdly, The use of this arterious infolding seems to be, that the blood may be distributed from its passages into the Membranes, viz. which is carried every where from them through the Ca­pillary Vessels; the reliques of which also are supped back by the little chanels sent [Page 181]out of the bosoms. Further, from this Store-house, if necessity urges, a certain pro­vision is had for the wants of the Brain; wherefore from hence the small Vessels end in the wonderful Net.

So much for the Arteries distributed about the Spine or Back-bone: the Vessels of the second sort are the Bosoms which come between the Arteries and the Veins for the use of the spinal Marrow no less than of the Head it self, and are here ordained with a more curious implication. But the reason why bosoms are required to these more noble parts, and scarce to any in the whole Body besides, is this; to wit, that about these bodies all manner of extravasation, or any stagnation of the blood, might be hindered: but sometimes the Veins are not sufficiently emptied, that they may presently receive from the Arteries the deposited blood, and so may prohibit any flow­ing out of it; wherefore the bosoms, as more fit receivers, are destinated to that office, for that their receptacles are larger and soon emptied; and for that reason they may more conveniently derive the blood from either medullar substance, lest it should overflow it in the Head or Spine.

As to the Figure of the Vertebral Bosom, its passages being conform to the arte­rious infolding, are put under it in the whole tract of the Spine: for after a like man­ner, in either bosom, which is extended within the cavity of the bony Den, from the hinder part of the Head to the Os Sacrum, there is one receiving Vessel, by whose twofold chanels presently the blood is brought back from either superficies of the Marrow into the bosom, and another carrying back, by whose passage the same is exported into the Veins. Moreover, in many Animals (though not in all) the bo­soms on either side seem to be knit together upon the knots between the Vertebrae by the cross processes, and so communicate between themselves: either bosom in its top is continued into the lateral bosoms of the Head; further, from it on both sides a passage lyes open into the Jugular Vein and into the Vertebral, Tab. 13. Fig. 4.

What the use of the aforesaid Bosom is in general was but now intimated; to wit, that the blood deposited from the Arteries in the spinal Marrow, might be presently emptied from thence, and be retained within the more large Cavities of the Bosoms, till it may be transferred into the Veins being made more empty: But the reason of the divers sorts of implications, and the frequent ingraffings which is found about their little chanels, seems to be, that the blood, if by chance it being plenti­fully heaped up within some part of the [...]osom, should there stagnate, or be apt to regurgitate into the Marrow, it might be drawn out by those frequent Emissaries here or there into the middle or opposite side: after a like manner it is with the bo­soms about the Spine, as when a Country-man digs in his ground frequent cross Fur­rows for the draining away any superfluous moisture.

There remains another use of the Vertebral Bosoms, of which we made mention before, to wit, that the blood nigh the medullar Body, being brought through their variously intorted Meanders, (like the arterious infoldings) might yield heat requi­site for the swift passage of the animal Spirits, as it were a Balneum Mariae. That the bending tracts and complications of the Bosoms may be the better seen, a cer­tain tincture may be cast into the Vertebral Veins; and presently that invading the passages of the bosoms and marking them, will exhibit the appearance of a long Lad­der with many little labels hanging to it.

Yea at length by those little roundles we are led to the third kind of Spinal Vessels, which are the Veins, into which all the bosoms immediately convey their burden, whereby they being continually emptied, may be still able to receive fresh blood: wherefore the venous branch is stretched out by the several joyntings of the Vertebrae into the bosom, which presently carries away the blood laid up in it, and to be re­duced towards the Heart. The Veins designed to this office, after the example of the Arteries, are disposed after one manner above the Heart, and after another be­low it. As to the first, a branch going from the Trunk of the Vena Cava below the Chanel-bone, or the first little Rib of the Breast, accompanies the Vertebral Artery, and ascending by the holes of the Processes between the several Vertebrae, inserts a little branch to the Bosom, Tab. 13. Fig. 2. h. h. h. Then the top of this Vein being carried towards the hinder part of the Head, is continued into the Trunk of the Bo­som, and opened by the other passage into the Jugular Vein. But further, as if these communications were not yet sufficient for the draining away the blood, transverse branches also are stretched out between both Veins, Tab. 13. Fig. 2. i. i. i. So mani­fold diverting places appear, by which it is enough and more than enough provided, [Page 182]lest the blood might flow back towards the medullar Trunk upon any occasion. Be­low the Heart, because the Trunk of the Vena Cava cannot, as the Aorta, immediate­ly lean upon the Spine, and carry shoots straight to the same, therefore it sends forth a Vein without a Companion, out of whose Trunk forked or twofold branches being sent forth, go forwards both to the Muscles of both sides and to the Spine it self. Be­low the Kidneys, seeing there is a space granted for the Vena Cava to be carried nigh the Spine, the Azygos Vein ends, and from the Trunk of the greater Vein, as from that of the Artery, the Vessels belonging to the Loyns immediately proceed.

These things being lately observed concerning the blood carrying Vessels belong­ing to the Spine and the hinder part of the Head, and here inserted in the place of an Appendix, ought to be referred to the other Doctrine of this kind, delivered above in the eighth Chapter. In the mean time, that we may return to our purpose, to wit, what remains of Neurologie, there is not much more to be met with worthy note con­cerning the Nerves: For they, as to the greater and chief Ramifications, are almost constantly both in Man and brute Beasts, after the manner we have described them. Sometimes it happens, although very rarely, concerning the divarications of the smallest Shoots and Fibres, that there is some variety: but as to the primary Vessels, and those drawn from them, the Configuration of every pair of Nerves is still the same or alike in all. It now remains, that the Theory of the Nerves, hitherto drawn in words, and so only objected to the Understanding, may also be shewn to the Sense, which will make it clearer. Wherefore we have taken care, that the ingraven De­lineations of the wandring and intercostal pair of Nerves, and also of others which are of chief note, and of the Spinal Marrow it self be plainly exhibited. The Fi­gures of these, although taken from a dead Example, yet after many Dissections and a frequent comparing them together according to their several parts, they are de­scribed as if from the life; the Lineaments of which with Characteristical Notes, that they may be the better and more distinctly perceived, and a large draught of every Figure, equal almost to the Scheme of Nerves in their animated Body, we have cau­sed to be cut: further, because the Contents of either side and of the Cavity between, cannot be at once described in their proper situation; therefore here it is supposed, That the Spine, with the oblong Marrow, or the whole medullar Stock, cut in the midst is rolled out, and both sides of it, with the pairs of the Nerves arising in the whole Tract, is turned outward.