1. BY Fermentation, I understand that motion observable in all compound or mixed bodies whereby the order and situ [...] on of all the minute parts of the same, are continually changed, as well in re­spect of themselves, as of the whole Mass whereof they are parts: and that, chiefly from an internal cause so moving or dispo­sing them, (without the local motion of the whole) whether the same be accompanied with any sensible heat, in the Mass so fer­mented, or not.

2. That such a motion or fermentation [...] every where observable, we need not go [...] to prove, if we consider, that there is [Page 2] scarce any thing sublunary, which is subject to our observation, that continues the least moment of time in the same tenour without alteration, which, if not observable to sence is yet found to be so, with as little reason­ing as that the shadow upon the Dyal con­tinually moves on, though our eye deter­mine not, till after some minutes, perhaps, of time, it becomes apparent, that the shadow has moved and then we straight conclude it moved all the while: and that the proportional parts of space, were com­mensurate to the respective moments, in which the shadow passed from one term to the other: if therefore all bodies are thus moved or fermented at all times, it fol­ [...]ows that the Doctrine of Fermentation (according to our acception of the word) [...] manner as far extended as that of [...] itself. I shall only consider it so [...] as it seems conducible and subservient to those noble ends I have proposed my self in this Treatise, viz. the continuation of health, the cure of Diseases, and the retard­ [...]ng of old Age (to say no more, and not [...]o promise too much) by a new and hitherto unheard of method.

[Page 3]3 The most general properties of fer­mentation are these: that the Mass so fer­mented suffers an eminent alteration in all its usual wayes of affecting our senses, as well in its first as second qualities: they are either exalted or depressed, they are some­times changed for their contrary, and in a word, relation being had to our esteem of things thus fermented, all fermentation may be said to be either perfective or de­structive, though in it self it be but one con­tinued flux: as for instance in an apple, or the like, that from a green austere bud, first acquires its due perfection, and after by a continuation of that fermentation, that ripened it, at last arrives at corruption, and so changes both its name and nature together.

4 Another eminent property of fermenta­tion, is that for the most part the Body fer­mented doth occupy more space than the same did before, which is very evident in the drowned bodies of men or other ani­mals, which though at first they go to the bottom, yet after a certain time do slowly boye themselves up again to the top of the water, not for that the breaking of the [Page 4] Gall becomes the cause of their ascending: (as some even knowing men have suffered themselves to be perswaded) but because such bodies formerly heavier than water, quantity for quantity, and consequently apt to sink, have now acquired a larger dimen­sion, while they however increase not their weight, and so becoming lighter than the water contained in the like space are pro­truded by it to the top where they by degrees swell yet bigger▪ so that some­times I have seen a dog lye with more than one halfe of his body above the sur­face of the water, and it is no more than happens in a pound of Glass, metal or other heavy material, which in a solid Mass sinks to the bottom, but if blown or wrought in­to a bottle, it keeps the top of the water: all which together with the reason is well enough known to such as have been con­versant in statick Experiments.

5 Another very useful property of Fer­mentation is, that while it separates all He­terogeneous parts, it leaves the Basis as it were, or main ingredient of the Mass clear and limpid, if not hindred by the den­sity of the body, and throws off two re­crements [Page 5] or superfluities, one a heavier descending to the bottom, the other of a lighter more frothy substance, which takes its place at the top of the liquor: as is mani­fest in Wine, Sider and the juices of other fruits: in Beer made with Barly, and the decoctions of other grains, first, maulted and grown'd. This happens not in Bread because the greatest part of the Mass being the more solid, the less or watry par [...] takes its flight on all sides to the circumference, though somewhat more slowly and there coagulates into a blew mould.

6. Another noble property of Fermentation, is, that it exalts the body fermented to what perfection it is capable of, but then it is requisite that the body fermented be of such a consistence, as may not be fer­mented too fast, as in fruits, upon trees: or if thin, that it be close stop't in some full Vessel, as all kind of drinks: or if o [...] [...] middle consistence, that it be often stirred▪ which is observed by Apothecaries in the making of Treacle, and other such Compositions, which afterward will keep a very long time. For thus it is necessary, that that spirit (as we will call it for the pre­sent) [Page 6] which ferments the Mass, be for a while detained either by the tone of the body, by some strong vessel; or that it be often re-effused, as it were, upon its body, that so by its long, difficult and reiterated working, it may at last find out some con­gruity amongst the less Heterogeneous parts, and cause a kind of complanation of the whole Mass, and it self with less re­luctancy, be detained in the Body or Mass.

7. Another very General property of Fermentation is, that all bodies, almost by it, at last become acide: as is manifest in all liquors, decoctions of flesh, or herbs, e­lectuaries, sirups, &c. by which acidity I un­derstand not that sowre taste, observable in most green fruits, which is rather to be termed acerbity, and differs as much from what we here speak of, as Agresta (the juyce of green grapes exprest) doth from Vinegar.

8. In the next place, let us briefly con­sider the causes of Fermentation, the most immediate of which, seems to be the Air, contained in every mixt body: for as I noted before, all bodies fermented, do occupy a larger room, than they did before [Page 7] fermentation: which cannot be duely a­scribed, to any other ingredient in mixt bodies, than to the air, for that it hath not yet been found, by sufficient experiment, that any body whatsoever is capable of rarifaction and condensation; or dilation and construction besides air: as for Leaf Gold, what it got in one dimension, it lost in the other, and all the parts of Gold calcined, do but equal the Mass they were made of, no more than if the same had been redu­ced to an impalpable powder by means of a very fine file. The same is to be understood of water evaporated by heat: which is only a comminution of it, into exceeding small parts, and no way a conversion of it into air (as hath been formerly received) which is from hence evidenced, that such vapours by the Alembic, are again reduci­ble to the same liquors from whence they were first raised, viz. into Rosewater or spirit of Wine, which were no more possi­ble, if they had been really converted into air, then out of common air to draw Rose-water or spirit of Wine, and if water, or milke or other liquor take up more room when boyling on the fire, then they did [Page 8] cold, 'tis by reason that the particles of air, formerly not visible are now considerably dilated, so as to become observable to the eye.

9. As the Air contained in mixt bodies, is the most immediat efficient cause of Fermen­tation: so it needs, exciting and actuating, for the most part, as well by the temper and tone of the Medium, as from the ad­dition, of this or that particular Ferment as of leven yeast, Renet, or the like: of which perhaps we shall have farther occasion to speak more, hereafter, and at present only consider how the Medium especially the Ambient Air, excites the internal air in the work of Fermentation.

10. By the Tone of the Air, I understand the measure of its rarity and density and especially its reciprocations or frequent access and recess to this or that degree of rarity and density. Now, that one Air is rarer than another as that of hills, then that of the valleys, that of southern Re­gions, then that of the more Northern: is I think an undoubted truth: also that the Air of every particular place is sometimes rarer sometimes denser according to the [Page 9] several seasons of the year, times of the day and night, &c. needs no other proof then that of the Weather-glass. By the temperature of the Air, I mean its degree and difference of heat and cold, which ad­mits of the same considerations of place and time as before, and is not only proved by the Weather-glass, but even by sense it self.

11. The manner how the Ambient works upon the internal air in mixed bodies, is the same with that of the Weather-glass, where the inclosed air is rarified, and condensed, heated and cooled accordingly, as the Me­dium is affected: So in bodies fermented, especially liquors, the imperceptible parti­cles of air being gently and by degrees di­lated, become the cause that the whole Mass doth occupy more and more room, or encreases its dimensions under the same weight, whereupon this effect immediate­ly follows, that several Heterogeneous Particles, which before floated in the li­quor, and were (as I may say) equilibrous with the same, do now gently descend to­ward the bottom, in order, according to their weight: The small Particles of air in [Page 10] the mean while being more and more dila­ted do, together with the more viscous parts of the liquor (of which they form themselves Coats or Integuments) gently ascend to the top of the Mass, where they make that frothy head or scum observable in Sider, Wine, Beer, and other liquors; and this I take to be the natural method of all ferment [...]tion when not checked, or other­wise determined by some outward circum­stance: And this also seems a genuine rea­son of the depuration, and of the casting off the heavier and lighter recrement men­tioned before (N. 5.) to happen in ferment­ed liquors.

12. That Bodies are ripened and acquire their due perfection by fermentation, is as­serted N. 6. but in such case it is necessary, that this fermentation be checked or re­tarded in such sort as is there mentioned, both in natural and more artificial fermen­tations: But the most universal Moderator of this motion, is what was lately call'd the tone of Air, as well as its temperature, which daily and hourly changing, doth ac­celerate, retard, check and put backward this motion, and then restores it again; by [Page 11] which various, and oft repeated course, the parts are comminuted, their roughness re­tunded and mitigated, and they so disposed of, after an inexplicable manner, as condu­ces most to the beauty and perfection of the Body fermented.

13. This dilatation and constriction in Bodies fermented, caused by the like acci­dents of the Ambient Air, may not im­properly be compared with the pulse in A­nimals having its Systole and Diastole, e­ven as they have, though by longer peri­ods, as of day and night, warm weather and cold, &c. and from hence perhaps is the true cause of pulses in Animals to be lookt for, which yet as forreign to our present scope we here enquire not farther after; but it will not be improper to ob­serve (with common experience) that Malt is best made in windy weather, and that the best and most lasting Beer is brewed in March and September, (windy moneths, and of an unequal temper) Now 'tis evi­dent, that all winds are moved by gusts rather then equal fluxes (from whence probably it is that the Sea is lifted into Waves, as it were numbring to us the seve­ral [Page 12] impetuous stroaks it received from the winds.) Thus the motion of all Animals seems to be performed by snatches and jerks; and it is indeed a great question a­mong School-Philosophers, whether any local motion be (strictly speaking) continu­al, and not rather consisting, of short moti­ons, and frequent rests, as it were com­pounded together. This Pulse, or frequent change in the tone of the Air, however it may seem at first view an idle or over-subtil contemplation, will upon due considerati­on, be found not only true, and the cause of those effects assigned to it in the foregoing Paragraph, but that it may also with good effect be made use of in Physick, as a nota­ble instrument for preservation of health, and the cure of diseases. I shall hereafter endeavour to prove in the ensuing dis­course. That most liquors fermented, especi­ally in the beginning, conceive heat, and become warm, even to sense the reason, may be partly gathered out of what has been already said; namely, that the small particles of Air in such liquor become di­lated, which dilatation is always accompa­nied with an encrease of heat, they mutu­ally [Page 13] making way for, and introducing one the other (in the Air and bodies participa­ting of Air) if not hindred from without; to which may be added, that all motion is apt to beget heat in the Body moved, which is true not only of solid Bodies, though more eminently in them, but also of liquid Bodies themselves. Thus 'tis said in making Butter, you must neither make too much at once, nor yet must it be too violently beaten or shaken, for in such case there will be great hazard of over-heat­ing the Butter, which as you see is the meer effect of motion in a liquid Body only▪ Besides most liquors fermented, abou [...] with a kind of Tartar (which afterw [...] subsideth when the Mass begins to co [...] the collision of whose rough particles [...] against the other, may perhaps somew [...] contribute to the production of this he [...] though I for my part impute less to [...] then the causes before assigned, though [...] remarkable heat arising in Aqua fortis a [...] sed upon filings of Iron or Silver, is perh [...] best made out by the collision of its aspro [...] parts against those of the said Metals.

14. As concerning particular ferments, I [Page 14] shall only observe, that congenerous Bodies suffer most, and are best fermented by their own proper ferments, namely Ale by yeast, Dough by Leven, Milk by Renet. Thus Apples, Pears and Grapes, and generally all fruit, once corrupted or rotten, do more easily affect and putrifie those of their own kind then of any other; I say more easily, for they will, though with more difficulty, and after a longer time, corrupt fruits of a divers kind also; and those particular Le­vens before-mentioned, will in like manner (though probably not so naturally) ferment [...]ther Bodies of whose kind they are not: [...]s Yest will ferment Dough (which yet [...] something congenerous to it, as pro [...]ng it self originally from Corn or [...];) and whites of Eggs bea [...] up [...] snowy froth, will indifferently supply [...]ant of Yest, in either Wort or Dough; [...]am verily perswaded, that the Yesty [...] which may be taken off the top of [...] running Drills of water, would effect [...]me mingled with Dough, unless per­ [...] it be not viscous enough, wherein it [...]ms only to differ from the whites of [...]ggs beaten as is said; and it were worth [Page 15] the trying to understand, whether a Mass of Dough made with flower and snow on­ly, would need any other raising or Leven. I have read, that in the Countryes about Parma and Piacenza, whence those so much valued Parmisan Cheeses come, the people make use of Snow instead of Renet. This instance however of the white of an Egg beaten, may serve very well to illustrate our Position concerning the fermentation of Bodies by the dilatation and constriction of its aereous Particles: as also the kneding of Dough, and shaking of liquors (which is a kind of kneding too) the better to make them rise and work, will notably confirm what we said of the Tone of the Air, its frequent alterations, and of windy weather, how much they conduce to the better fermentation of most Bodies.

15. Note, that the reason why the juices of most fruits do soon after expression ac­quire a strong fermentation, seems to be this, that not only the liquor is now more at liberty, then when mixed with the fleshy parts of the fruit, but likewise that the Airy Particles lay very much compres­sed in the fruit, every particular Grape, [Page 16] Cherry and Apple, being in the nature of a little Bottle, which as we see, if well stopt, hinders the working of Ale or Wine, but once opened, the liquors straightway fer­ment and swell very impetuously, the com­pressed Air forcibly dilating it self; and this is the reason that fruit a little eaten by the Birds or Snails, will ripen much faster than if they had not been entered upon, (but then the taste will not be altogether so generous and sprightly.) Thus Apples and Pears gather'd green and hoarded, ri­pen sooner far, than if they had continued hanging on the Trees, for that they now receive some vent at their stalks; and I find the Ancients were wont to plant the Caprificus (or wild Fig-tree) neer their o­ther domestick Fig-trees, that so the Flees which in great quantities are bred out of the fruit of the Caprificus, may seize and pierce the Figs of the other trees, as they do in several places, thereby not only acce­lerating their time of maturity, but also (which perhaps is particular to this kind of fruit) rendring them much more tender and delightful than otherwise they would have been, had no such Artifice been made [Page 17] use of. Now as we have said, this kind of fermentation whereby fruits attain their maturity, bears a very due proportion with that observed in botled drinks, which if well stopt are slower in ripening (but of better taste) than in open vessels: as also if placed in cold well-vaulted Cellars, then if exposed to the Air: and that for this reason, that the difference of heat and cold (especially in Summer) is by many degrees more in the open Air, than in such subterraneous Vaults, and consequently the Aerous Particles, contained in such ferment­ed liquors, are more dilated and constricted (reciprocally) when exposed to the wea­ther, than if laid up in Cellars, or buried in the ground. Which reciprocation of the tone of Air, we have already asserted to be the principal, if not the only cause of all fermentation. And it may be farther illu­strated, by a common practise of botling up Wine, or other drink, with a lump of Loaf-sugar in it, which will make it much more brisk and lively. And this it d [...]th, not by its sweetness sure, for that were apter to clog and tame it, as is found by practise; or if it did, then Syrup of Sugar, or a small quanti­ty [Page] of powder Sugar, might indifferently produce the same effect: which yet is contradicted by experience. Nay, I dare confi­dently affirm, that the like quantity of the fame Loaf-sugar, first done into very fine powder, will not serve the turn. So that I cannot imagine other reason, why the lump of Loaf-sugar is of that use, put into bot­led wine, &c. than that being very porous, it conveys with it self, a great quantity of air into the liquor: and does in effect no more, than what has been already said of the whites of Eggs beaten up together into a froth. So it is not the Sugar, but the air contained in the sugar, which mends the fermentation of the drink, and whereby the Sugar supplies the place of an additi­onal ferment, the better to excite the working of the liquor.

16. And lastly, methinks it might alone serve turn, to convince us of the great effi­cacy the air hath, and the power it exer­ciseth on all or most mixed Bodies: what we finde to manifest by experience in pre­serving of flesh, fruits, the Bodies of In­sects, and other the like, whether for ali­ments or curiosity only, and that with lit­tle [Page 19] other preparation many times, than by barely immersing them in wax, oyl, butter, sewet, some Gum or Rosine, &c. and after­ward carefully putting them up into Vessels well stopped. By which practise we seem to obtain little else, than that we do here­by, as it were, conceal those Bodies, thus preserved, from the air, which would o­therwise, in a short time, have totally cor­rupted them: their long continuance and preservation seeming to follow, as the con­sequence of that artificial exclusion of the air, whereby the Bodies (or rather the air in them) are no longer apt to be affected, according to the various dispositions of the Medium.

Farther, it is well worth our Observati­on, that Chyle, Milk, Cream, the seeds of all Vegetables, and even that of Animals it self, seem to owe their whiteness, to the interspersion or dissemination of air only: even after the same manner, as is already observed in Snow, and some other Bodies.

1. THe Stomack or Ventricle in animals, designed by Nature for the Office of Chylification, commonly called the first Concoction (and which is, as it were, the root of all Vegetation or nutrition in them) seems at first birth but ill fitted for such a work, till the Coats or Membrances there­of, have been well stained or seasoned by the receipt of an aliment so prepared, that it want little more than warmth, to the per­fecting of that operation upon it, which is expected from the Stomack. And thus, for all animals that suck, Nature has provided for their first food, a kind of corrupted Milk, usually called Beastings, which gives, as it were, the first tincture to their tender Stomacks, and whereby they seem enabled to concoct more perfect Milk, [Page 21] which they begin to draw after a day or two. Which Milk also by degrees becomes more thick and harder of concoction, pro­portionably to the encrease of strength, in the stomack it self, till by little and little, they begin to alter their diet, and forsake the Teat, for such other food as is most proportionable to their respective Natures.

2. This Tincture, thus imprinted on the Stomack, may very properly be termed a ferment, and seems to bear a just proporti­on with Leven, which is a small part of the Mass of Dough, suffered to grow sowre, while the rest is converted into bread, which if not hindred, would have all turn­ed into leven likewise. Thus after the Chyle is conveyed from the Stomack into the Guts, from thence to be distributed through the whole Body: some small part that remains sticking to the coats of the Stomack, soon after acquires that acidity, due to all fermentation not interrupted: which after some time begins to grieve and afflict the Stomack with its sharpness: the sense whereof, we usually call hunger: which sense of pain (or hunger) continues to grow more and more, (that which caused [Page 22] it becoming still sharper and sharper) till by the reception of new aliment, the acidity of the said Tincture or Leven, be so mi­tigated and allayed, that the Stomack be­ing, as it were, healed by application of these new, benigne, and uncorrupted juices, is no longer sensible of any pain or molesta­tion: which then puts an end to the desire of eating. But if food be forborn, or withheld, the pain so long encreases, till it at last destroys the sense of the part, and introduces a sphalelus, Gangrene or Mortifi­cation in the Stomack: which is afterward soon conveyed to the heart and brain, by its communion of Vessels, and so at length becomes the death of the Animal. Which seems rather to be the cause of death, in such as perish by hunger, than the empti­ness or inanition of the Vessels, which, though much exhausted, are yet found in such cases, with a considerable quantity of blood in them. Nay, 'tis a frequent pra­ctise in the Desarts of Arabia (as I am in­formed by some that have travelled in the Levant) to let their Camels blood after se­veral days fasting, and to give them their own blood to drink, as the last means left [Page 23] to preserve their lives. Which practise, as it cannot replenish the veins, to that mea­sure it already emptied them: so it evi­dently concludes, that emptiness of the Vessels, is not the true cause, of perishing for want of food. Much less can the continua­tion of Suction, from the exhausted Vessels to the Stomack, be the cause of hunger. For first, such hunger could not be imme­diately appeased after eating, the Vessels receiving no part thereof, till a considera­ble time after, when distribution begins to succeed concoction, as is well known and confessed. Secondly, 'twill appear to such as shall duly consider it, that the Vessels or Veins are then fullest, when the Stomack is emptiest (& è contra) the emptying of the Stomack, beginning with the filling of the Guts, and Veins. Nor shall we need o­ther arguments, against this Suction (though it were easie to charge it with more difficul­ties) than that the owners of it, will be forced to prove, there is some such power of moving by attraction, drawing or Sucti­on, which will be a harder matter than it appears at first sight. Though as not making to our present purpose, I shall not deter­mine ought, concerning it.

[Page 24]3. In confirmation of this our Assertion▪ viz. That the concoction of the stomack is a kind of fermentation, it will not b [...] a­miss to shew the reason of some circumstan­ces of it. And first, concerning that preparation, which meat receives in the mouth, by chewing or jawing of it, which is rather a bruising than mincing: and it is a common observation, that flesh minced very small, is of much harder concoction, than if eaten by bigger pieces; and a sufficient reason is withall assigned, that meat minced, slips down into the stomack, before it be duly masticated or chewed, which is so necessa­ry an antecedent of concoction, that the Arabian Physitians are wont to say, That he that chaws not his meat well, hates his own Soul. Now that any thing bruised will soon after corrupt, is evident in all fruits: which will sooner putrisie, after bruising, than if they were cut with a sharp knife in­to many pieces. Thus a flesh-wound, made without bruising, will commonly heal again with little or no corruption, but not if the part were bruised at the same time. Thus the common practise is to bruise Whitloes, to ripen and break them the sooner. And [Page 25] thus to conclude, our meat by being brui­ [...]ed, becomes of much easier and speedier concoction, which seems to be the reason why Nature has given to most Creatures, namely, Dogs, Wolfes, Swine, Foxes, &c. three sorts of teeth; to wit, Tusks to kill their prey with, sharp fore-teeth or cutters, wherewith they tear it into smaller pieces: And lastly, Grinders to chew and bruise it, the better to prepare it for the sto­mack.

Birds seem to grinde their meat in their Gizards, after it is first well soak­ed in their craps, for which purpose they pick up sharp stones, and their stomacks are made of two large Muscles; one, on either side: the chief instruments in this work of Moliture, or grinding. The Locusta or Lob­sters has his teeth placed in his stomack, and so have the rest of that kind, which they imploy for the same purpose.

4. Our next observation shall be upon two Rules of Diet, commonly given by Physitians: the one is, that we should not put new meat into our stomack, till after a perfect digestion of what was eaten the meal before: the reason of which Rule, [Page 26] seems to be this; That it is necessary th [...] stomack, should continue some time empty, that so the Fracid Tincture, or small cor­rupted remaining portion, of the former meat, may have acquired its due acidity: whereby it may the better help the suc­ceeding fermentation or concoction. And it is no more than if you should advise the House-wife, not to make any new Bread till the Leven be grown ripe, or sowre enough to leven and ferment the Mass of Dough. The second Rule is, that we should leave eating, with some small appetite to eat on; or that we should rise from Table with an appetite: the reason is almost the same with the former, and may well be il­lustrated by the same instance, which is, that it is requisite, the Leven should bear some just proportion, to the Mass it is to ferment. Thus if we rise with an appetite, it will appear that we have not over-char­ged this ferment of our stomacks, for ap­petite being, as is said, a sense of pain cau­sed by the sharpness of this acid ferment; it follows, that this acidity is not yet quite obscured by the late mixture of good, and consequently the stomack, not charged with [Page 27] more, than may be well digested, at once by [...]. And these are Rules, very fit to be ob­served, as well by those which are of a more robust nature, as of them (especially) who have weak stomacks, and find them­selves indisposed after eating.

5. 'Tis further advised by some Physiti­ans, that such as have weak stomacks, should forbear drinking, till they have neer dined: and we commonly observe, that drinking just before dinner, spoils our eating, which it does, by diluting this ferment of the sto­mack, whereupon the sense of pain, and consequently hunger, abates very much, or quite ceases for a time. And 'tis usually seen, that they who are great Drinkers, are bad Trencher-men: and that as well, for that much drinking relaxes the tone, and extenuates the coats of the stomack, as more especially, for that it washes away by little and little, all this fracid tincture, or sowre ferment, of the membranes thereof, which is as well the cause of concoction, as of appetite or hunger.

6. Bulls Blood drunk, was found a present poyson by the Ancients, and Milk taken plentifully, and after curdling on the sto­mack, [Page 28] has often been the cause of great and mortal Surfeits: the reason of both is the same; for that, both blood and milk being curdled, and brought into one hard lump, becomes insuperable to the stomack. Whereas, if the same be suffered to coagu­late (before they be eaten) and broken into small parts, they will have no such effect, and instead of poysoning, will afford an in­different good nourishment to the body: So far seems Helmont to have missed the mark, when he says, The cause of this poy­son is, Imago Irae, in Sanguine Taurino. And I doubt not but a lump of Beef, or a piece of Cheese, of the same bigness, whole in the stomack, would as surely poyson, if not more effectually. And this may farther con­firm, what is said in the third paragraph, of preparing our Food, by chawing, &c.

7. The inward membranes, or skins of the Gizards of most Birds (especially such as feed on corn) prepared, by drying and powdring them, are held a great help to concoction. Now the acidity of them is ve­ry manifest, and no doubt they do no other­wise comfort our stomacks, than by en­creasing and corroborating that ferment so [Page 29] often mentioned. Thus, the dung of seve­ral Animals prepared, namely of Wolves, Dogs, Peacocks, &c. have been approved of in divers diseases, or distempers of the stomack and guts, for the same cause. Nay, I have heard that Paracelsus, his Occidental Civet prepared, will make an excellent Peptick, for them that can dispense with such homely remedies.

8. It is a famous Question among Physiti­ans, Whether it be better to make a meal of one only dish of meat, or to eat of se­veral meats at the same setting? and it is commonly determined, in favour of the simpler diet. But it seems more consonant to our Opinion, to allow rather of several dishes; for that which is easie of concocti­on, will help to concoct that which is har­der. Thus good Sauces to meats make them set easie, and light, upon the stomack: the Sauces (being easie of concoction) helping the dissolution of the meats. And we may surely expect, a heartier nourishment from them, than single dishes; as we find by ex­perience, better broth to be made of seve­ral sorts of flesh, than of any one; and com­monly the more variety, the more perfect [Page 30] is the pottage. And its well known, we are nourished by juices only, and not by the solid part of our food.

9. Where this ferment of the stomack is more acid than is requisite (as it is in Hy­pochondriacal persons, and such as are troubled with sowre belches) 'tis found by experience, that to make two, three, or four meals in a day, is better than one: and that fasting encreases much the acidity. Tha [...] hard meats, as dry bread, Biscuits, and those that are less easie concoction, are more use­ful than Broths (and other light meats:) which will sometimes (especially taken in a morning, the ferment after long emptiness becoming extraordinary sowre) work so vi­olently, that they will flow up into the mouth, and with their eagerness, set the teeth an edge, and ferment the very ground. But both in this, and the former rule, 'twill be necessary to take some care, that we do not eat much more of our Ma­ny dishes, than we should have eat of one, and that the quantity of our meat, at many meals, but equals, or not much exceeds, what we should have eaten at once or twice.

[Page 31]10. 'Tis observed, that sudden change of diet has sometimes proved very fatal, and been often the occasion of dangerous disea­ses. The reason may well be, that the sto­mack, having received its tincture or ferment from food of another nature, is but ill pre­pared for the concoction of those meats, to which it hath not been accustomed, and from which it has as yet received no stain or impression. Such changes therefore must be made by degrees; and thus I have heard, that horses have been brought to live upon flesh: and some men, have indifferently well supported life, with bread and herbs only.

11. Wolves are said, when pressed with extremity of hunger, sometimes to tear the ground, and fill their panches with meer earth: which surely affords them lit­tle or no nourishment. But it serves for the present, to abate the edge of their appe­tites, till they meet with some prey, at which time, they easily discharge their sto­macks of the earth, and fall to better meat. This instance may indifferently well support our Assertion, that hunger is ra­ther a sense of pain from the acid ferment [Page 32] of the stomack, than of emptiness from the Suction of the veins.

12. As concoction succeeds best with rest, so motion is said to help distribution▪ Now by distribution, we are to understand the dispersing, of the thinner parts of the Chyle into the milky veins, from thence into the Subclavials, thence into the right Ventricle of the heart, where the Chyle already is pretty well stained, or imperfect­ly mingled with blood: from whence it takes its course to the lungs, where by the reci­procations of that part, it is yet more per­fectly, mixed with the blood. From the lungs, it descends into the hearts left Ven­tricle: from whence, it is thrown into the Arteries: where by degrees it receives the form and name of blood: and by them is conveyed into all parts of the body. In re­gard the milky veins, have no attractive power, whereby the Chyle might be suckt into them (as far as could yet be fairly made appear) nor has the Chyle (much less) any such inclination or power of moving it self that way; it remains, that this distribution of the Chyle, is performed by the motion of the body. And thus we find moderate [Page 33] exercise, soon causes an emptiness in the [...]irst ways, and begets an appetite. And yet we may likewise observe, that while we sit still, or sleep, this distribution is performed, though not so speedily. Now while we rest, there is no other motion observeable, beside that of breathing, which seems to be the true cause of this distribution of the Chyle, till it comes into the Subclavials: for when we draw in our breaths, the Dia­phragme or Midriff compresseth the sto­mack, and gently forceth the Chyle thence into the guts. And again, when we breath out, the Muscles of the belly straight sub­side, and strongly compress the guts; whereupon the thinner part of the Chyle insinuates it self into the mouths of the milky veins, and by the succeeding parts of the Chyle, is protruded into the Sub­clavials, where afterward it is moved with the motion of the blood. I do not deny the Peristaltick motion of the Intestines, (whereby the guts distended with Chyle beyond their due tone, do again by their transverse fibres contract themselves) for this is also a partial cause of distribution (as appears in the dissection of live Ani­mals, [Page 34] where this motion of the Chyle con­tinues after the Abdomen or belly is laid o­pen from one end to the other) but is much strengthened, no doubt, by the Muscles of the belly; besides this Peristaltick motion of the guts, shews indeed in part how they are emptied, but not how they are fitted with Chyle, which is the first part of distribution.

13. 'Tis worthy observation, that Butter melted, and very well beaten (or drawn) the while, becomes a much pleasanter cause, and easier of digestion, than if it be not beaten; and yet all the difference is, that by beating a great quantity of Air, is every where mingled with it, whereby it very much helps the fermentation or con­coction of our meat in our stomacks, after the same manner as is already said of whites of Eggs, in the former Chapter; and in­deed all sauses are a kind of additional fer­ments. That there is great quantity of air in Butter thus beaten, may not only be ga­thered from hence, that after beating, it takes up more room than it did before, or otherwise would do, if not beaten; but the same particles of air are even manifest to [Page 35] sense it self, and the whole Mass of Butter appears, beaten up, into a froth, so far is [...]t from being made thicker thereby, (as we commonly express our Opinions of it) [...]hat indeed it becomes much thinner and lighter, if compared quantity with quanti­ty, as is manifest.

interN. 1.THat Animals breath not at all, while in the womb, is most pro­bable, that all viperous creatures, after the birth, cannot live long without breath, is most certain; yet I do not find the uses of Respiration so clearly determined, but that it may afford us matter for farther en­quiry. The common received Opinion is, that Respiration serves chiefly for cooling the heart, next that, it yields matter for production of new vital spirits; and lastly, that it discharges the lungs of a fuliginous [Page 36] excrement, which seems to transsude from the Mass of blood into the branches of the rough Artery: that the heart is cooled by breathing, is very probable, but not imme­diately; for the air going no farther than the lungs, first cools them, next the blood in them, and consequently the heart be­comes less hot, than otherwise it would be; but this is, in effect, no more than is obtained by bathing the limbs in cold wa­ter, which does a together (if n [...]t more effectually) cool the Mass of blood, as much as the air in breathing can be concei­ved to do it, and yet bathing will in no wise become a Substitute to breathing. Nor does the generation of vital spirits seem to be the chief use of the air in breathing, in regard it is not easie to conceive any such contrivance in the lungs, that may serve for the letting in of air, into the veins and ar­teries, which contain the blood, without endangering, contrariwise, the effusion of that precious juice, much less has Anato­my, as yet, discovered any such passages unto us. Lastly, as I shall not deny, but that the lungs do discharge themselves of a fuliginous excrement by breathing; so I [Page 37] think it as true, that this is none of the principal uses of Respiration. Nor is it at all likely, that either the heart should grow so hot, or that the vital spirits should vanish so fast, or the fuliginous excrement be ac­cumulated in that quantity, upon the inter­mission of breathing for a short time only, as to indanger our lives beyond recovery, as the absolute necessity of Respiration would seem to inforce. Before I come to deliver my own Opinion, I shall make a slight digression concerning the circulation of the blood, which will not a little illu­strate what we are about to say concerning this Subject.

2. 'Tis manifest in the circulation of the blood in Animals, that the blood is moved from the left Ventricle of the heart, through the great Artery, into all its bran­ches, from whence it is brought back by the smaller veins, which discharge them­selves into the Vena Cava, from whence it is returned into the right Ventricle of the heart, from whence it is sent by the Vena Arteriosa into the lungs, and so brought back again into the left Ventricle of the heart by the Arteria Venosa: And in this [Page 38] circular motion of the blood, life chiefly consisteth: and if the same by any chance should cease or intermit, though but for a very small time (less than a minute) death would unavoidably follow. In this motion of the blood, it is observable first, that as the pulsation of the heart sendeth it through the Arteries, into the whole habit of the body, so the return of it by the veins, seems to depend chiefly upon the tonical motion of the body; for the parts being extended by the flowing in of the blood, somewhat beyond their tone, do a­gain gently subside, and thereby continue the intended course of the blood toward the heart again. An argument hereof is, that all Paralytick parts grow immediately cold, and that for no other reason, than that the tonical motion, together with the power Locomotive, ceasing, the circulation is either very weakly, or not at all perform­ed through that part, which then grows cold, for want of that constant fresh supply of blood, which formerly kept it warm. But herein the tonical motion is not a little helped by exercise and labour, which we find, by experience, to cause the heart to [Page 39] beat quicker and oftner, as also to induce a necessity of breathing more frequently; and this it doth no otherwise, than by ac­celerating this circular motion of the blood, which then enforceth the heart and lungs to double duty. Our second observable in this circular motion of the blood is, that there passes as much blood from the right Ventricle of the heart into the [...]u [...]gs, at e­very pulse (taking one time with another) as is sent from the left Ventricle into all the parts of the body beside. Nor can it be otherwise, the left Ventricle being supplied from the lungs only; and the lungs recei­ving it, not elsewhere than from the right Ventricle of the heart. So, that to continue this circular motion of the blood, 'tis ne­cessary, the supply neither exceed, nor come short of that quantity, dispensed from the left Ventricle of the heart, into the whole body (the Lungs excepted.) From hence it follows, that there flows a greater quantity of blood, by many degrees, into the lungs, than what is sufficient for its own private use. As also, that the blood in the lungs, must of necessity, move very much faster, than it does in any part of the [Page 40] body: though we take for example, the great vein or artery themselves: and that, in the same proportion, as the Vena Arterio­sa, and Arteria Venosa, are smaller than the trunks of the foresaid great vessels. For, let the same quantity of liquor be conveyed through a pipe, whose capacity is but one fourth, or one tenth, so big as another pipe, through which the like quantity must pass in the same time: and it is evi­dent, the liquor must run four times, or ten times as fast, through the smaller pipe, as it does through the greater. And thus, it appears, that a very considerable part of the Mass of blood, is continually running through the Parenchyma of the lungs; and that, at a much swifter rate, than it doth, through any part of the whole body be­side.

3. Farther, before we proceed to treat of the use of Respiration, it will not be amiss to consider, what kind of motion that is which the lungs are exercised with, in breathing. Nor is it any other, than a mo­tion of dilatation and constriction; where­by the lungs are reciprocally opened and shut, somewhat after the manner, of a pair [Page 41] of Organ-Bellows: the air entring into them, when dilated or opened, and rece­ding again, upon their subsiding. And this is what we call Respiration. Nor yet, does this reciprocation of the lungs, proceed from any power to move, they are endow­ed with of themselves. For, if we consi­der, the frame and structure of them, they will appear of a Parenchymous kind of sub­stance, not much unlike the liver, and al­together void of Muscles; without which, no local motion can be performed. We may conclude therefore, that the lungs are mo­ved by consent, and that chiefly of the Diaphragme or Midriff, in a free and ordi­nary breathing. But, in any difficulty of breathing, as in the Asthma, Tabes, violent exercise, &c. not only the Midriff, but al­most all the Muscles of the trunk of the body, namely, those of the Belly, Chest and Shoulders, seem to afford their assi­stance, in this great work of Respiration. The motion of the Midriff is first down­wards; whereupon the lungs follow, and the air is admitted, and again upwards; whereby the lungs are compressed, and the air excluded. Thus you see, that as the con­struction [Page 42] of the Midriff, so is its motion, somewhat different from that of other Muscles: which, as being well known, we shall not need to spend longer time about, but come to the publick use of the lungs, in the Oeconomy of our bodies.

4. In the circulation of the blood, we ascribed the reduction of it again into the right ventricle of the heart, to the Tonical motion of the body: where yet, as we have said, the blood moves but very slowly, if compared, with that swift, and rapid moti­on, it is carried on with, through the lungs; where it moves, perhaps, ten times as fast, as in any other part of the body; as has been already proved. Which notwithstand­ing, we shall not be able, upon perusal of the structure of the lungs, to conclude, that they are endowed with any considerable tonical motion, as may be gathered, as well from their want of Muscles, as for that their substance, is very spongey and flaccid: and their common integument is but one thin membrane. Nor was it without a par­ticular, and that a most excellent design: that Nature thus contrived the lungs with little or no tonical motion in them. For first, had this Tone been equivalent to the [Page 43] Mass of blood, to be returned by it; it would much have retarded the influx of the blood, into the lungs: and consequently, have hindered a great work of Nature up­on it there, as shall be shewed hereafter. But chiefly, for that it has largely supplied such defect, by the assistance of the Dia­phragme▪ which becomes the cause, both of dilating, and contracting the lungs; ac­cording to the occasion, and at the will and pleasure of the Animal. And this is, indeed, the first and principal Office of the lungs; as to what concerns their reciprocal moti­on: Namely, that upon the subsiding of them, in Respiration, the blood may be vi­gorously squeezed out of them, through the Arteria Venosa, into the hearts left Ventricle. And because, the substance of the lungs is very tender; Nature con­trives, that not the Diaphragme immediate­ly, but the air inclosed in the cavity of the brest (for this very purpose only) being first, streightened and crowded, as it were, together, by the motion of the Diaphragm upward, should cause this compression upon the lungs; while by its Elastic pow­er, it endeavours to dilate it self again, to [Page 44] its usual dimensions. Nor could any way of compressing the lungs, (thereby to dis­charge them of the superfluous blood) have been contrived more equal: for this pent air, is as apt to press upon one part, as on another. Nor yet more gentle, and secure: for what contact could have been more de­licate, or less apt, to wound the tender membrane of the lungs, than the air in­closed in the brest about them? Nor need any doubt, but that the air, thus comprest and streightned, is of strength sufficient for this service: and that there is such a Spring in the air; who, shall but consider with what force, the air breaks forth of the Wind-gun, and other Pneumatic Engines. A farther confirmation hereof, may be had from hence: that such wounds, as perfo­rate the brest, if left open, but for a little time, do quickly cause a difficulty of breathing▪ and I do not much question, but if both sides of the brest were perforated, it would as certainly dispatch a man, as hanging; and that, almost, in as short a time. Farther, in the dissection of live Animals, Respiration continues, long after the Abdomen or belly is laid open; but [Page 45] immediately ceases, upon dividing the Dia­phragme or Midriff.

5. Whether the air, that enters into the lungs, by the Wind-pipe, have a share in this compression of them, for the dischar­ging of the blood, or not, I am as yet not well satisfied. At first view, this compres­sion should seem, to be best made upon drawing in our breath; between the air implanted in the cavity of the brest, and the air, in the rough Arteries: (or bran­ches of the Wind-pipe) but at such time, the implanted air, is but little or not at all contracted: and therefore we must con­clude, that either the air taken in, bears no part in this compression: or which is most probable, that the sanguine Vessels of the lungs, are not only strongly com­pressed, upon expirations; but also upon inspiration; that is, so often, as the lungs are removed from their natural, middle, or indifferent scituation: whether expanded or contracted. Viz. Tàm in quiete externâ, quàm internâ. We must likewise allow the air to cool the lungs very considerably, and that it discharges them of a fuliginous, or rather vaporous excrement. But these are, [Page 46] [...]s we have said, the less principal uses of Re­spiration. As for the airs becoming the mat­ter of Vital Spirits in Respiration, I shall say no more, than that I neither find any need of it, nor any may for the mingling of it, with the Mass of blood.

6. Allowing what has been said, concern­ [...]ng [...]he use of respiration: we may, perhaps, [...]nd out a more commodious reason of sigh­ing, than has been yet assigned. For, if a man shall for a while, either wholly forbear breathing: or, at least, breath seldomer, [...]nd lower, than is his usual custom: the [...]unges, in the mean time, swell and fill [...]hemselves with blood, (for want, of that [...]requent and strenuous compression, for­merly equal to the influx of the blood,) while the pulse is not so full as ordinarily: [...]he hearts left Ventricle not receiving its [...]ue supply from the lungs, which in this [...]ase receive more than they deliver: Here­ [...]pon a man is necessitated, (for avoiding [...]uffocation) to fetch a great breath, or [...]gh, which may more strongly, than usu­ [...]lly, compress the substance of the lungs, [...]nd reduce them to their former estate. And thus, great attention, any deep con­templation, [Page 47] sad thoughts, and a melancho­lick constitution; do often become the cause of frequent sighing: As also, a natu­ral sloth, or less aptness in the lungs themselves, or Diaphragme, to motion: will sometimes make this passion customary, and habitual. And it is observable, that the pulse rises very much upon sighing; for the first stroak, or two, at least: the blood coming to the Artery again, in that abun­dance, that a man may feel the tingling of it, at his very fingers ends.

7. Furthermore, it may not a little strengthen our Assertion, that in all great difficulties of breathing: and where there is most imminent danger of suffocation, to let blood in good quantity, is commonly prescribed, as the last remedy: and which seldome fails, of giving, at least, a present relief, let the cause be what it may be. And this it seems to do, by diverting the course of blood from the lungs; while they gently again discharge themselves of their burden. And in case of hanging, or strang­ling, letting of blood in great quantity, has sometimes saved mens lives that have been executed; and this by no other ways, that [Page 48] I can think of, than by helping to discharge the lungs of their oppression, as has been already said.

8. And thus we have, if our Opinion fail us not, discovered the true use of Re­spiration. We have, also of consequence, freed the heart, of almost one half of the task imposed on it, by the modern Physiti­ans. For since the circulation of the blood consists of two parts, viz. First, the con­veying it from the heart, or center, to the rest of the body, as to a kind of natural circumference. And secondly, the return­ing, or bringing back of the blood again, to the heart. The first part, we conceive to be the Office of the heart. The second part, seems to be the work of every parti­cular member, to discharge it self of its own superfluities: For which purpose, na­ture hath endued them with a tone, or to­nical motion, sufficient for that service, the lungs only excepted, wherein Nature hath worthily imployed her industry, by the additional contrivance of Respiration, through the assistance of the Diaphragme: which labour of the lungs, in Respiration, for the returning of the blood to the left [Page 49] Ventricle of the heart; seems to equal that of the tone, or tonical motion, of all the other parts of the body; for the lungs convey the same quantity, with all the rest: that is to say, the whole Mass of blood, through them; and that in as little time, as the same passes through the rest of the body. And, if it carries it not so far, it moves [...]t so much the faster. And so, we shall have entitled the lungs, to one full quarter part, of this work of the circulati­on of the blood, leaving an other quarter to the tonical motion of the body: And the first, and worthier half, of dispensing blood and life through the whole body, to the heart, as its proper office and duty. What part, the lungs may justly claim to themselves, in the business of Sanguificati­on, we shall more conveniently find place to consider of, in the following Chapter.

interN. 1.THe Chyle, when separated from the remaining unprofitable parts of our Aliment is, by proper vessels of its own (the discovery of modern Anatomists) conveyed directly into the Subclavial veins, and from thence into the right Ventricle of the heart, where it is mingled with a lar­ger quantity of blood, returning home by the great vein, together with which it is immediately transmitted to the lungs, where (though it make great hast through, and moves very impetuously, as has been said, yet) by reason of the length of the way, it continues a considerable time, and is more perfectly mingled with the blood, and wrought up together with it, into one Mass, and at the same time, acquires both the name and form of blood (as Physitians term it) and so is fitted for the heart, from thence to be distributed to the rest of the body: where after what manner it is cir­culated, [Page 51] we say not, as a thing already suffi­ciently known, and whereof we have deli­vered our sense already.

2. That Chyle is very easily mixt with blood, is evident, for that it is the matter whereof all blood is made, by a farther continuation, of that fermentation or con­coction, begun on it in the stomack. Nor yet is the proportion so great between them, but that upon mingling; the dissimi­litude of parts, becomes immediately the cause of an extraordinary ebullition: which is very much encreased by the reciprocal motion of the lungs, whereby the blood is wrought almost all into a froth or foam, by that time it gets into the left Ventricle of the heart. Which sudden excess of heat, is not unlike what happens upon the min­gling several Chymical liquors together, as Spirit of Wine, and Spirit of Turpentine, and other such like, where the heat be­comes so great, that it often endangers the vessel they are contained in. And this is the cause of that heat a while after meals discernable in Hectical persons, and others, otherwise affected: and which in many ap­pears, by flushings in the face. Now that [Page 52] the blood is wrought up to that froth, we speak of, during its passage through the lungs, is not only suitable to reason, but appears most evidently, in those sanguine excretions from the lungs, which happen in consumptive persons: nor does that frothi­ness, then observable, proceed from the mingling with it the air we breath, for that at one breathing out (or expiration) could not be sufficiently performed.

3. The blood, by several very learned men, has not unaptly been compared to wine; and in my Opinion, the Chyle may as properly be likened to the juice, newly pressed out of the Grapes: which if it were by certain intervals, in a due proportion, poured gently into new wine, or must, as it begins to cool, would again renew its e­bullition, and continue the warmth of it, to what degree is requisite, and that so long as this practise shall be continued. And from this Illustration▪ may be clearly ga­ther'd; the necessity and use of eating, at least within certain periods, or intervals: to wit, that by the frequent affusion of Chyle, the blood may again recover its motion, warmth and vigour, without which [Page 53] supply, it would soon languish, cool and congeal, and consequently, death ensue. Now that the lungs are indeed the princi­pal Officina Sanguinis, may be farther colle­cted from Consumptions of the lungs, wherein all parts of the body are so sudden­ly extenuated, by the affection of the part.

4. 'Tis probable, that the blood during its stay in the lungs, does not actually dilate it self, and rise into froth, but only ac­quires an aptness so to do, as soon as it is at a little more liberty, as appears in blood spit out of them; and consequently; when it falls into the left Ventricle of the heart, it immediately dilates it self with great force, in the manner of botled Beer; and in this manner does, for ought I know, in great part, become the cause of the Dia­stole, or expansion of the heart, which being extended, beyond its due and natural scituation, does again violently contract it self, by a power almost all bodies have of restoring themselves, and which we call the tone, or tonical motion. And as we ob­serve in a Switch bowed down, or in a Pen­dulum removed out of its place, that they return beyond the perpendicular; so it [Page 54] fares in this motion of the heart, whereby it is again more contracted, than is natural to it, and so of it self returns again to ex­pand it self, and is again violently distend­ed, as before, by the influx of more spumy blood from the lungs. Now though it may be objected, that the pulse in the heart continues, many times, a long while, after it is taken out of the body; and when there is no longer any such influx to be pretend­ed, as the cause of it. To this I answer, that such pulse, is what the Physitians call the Myurus, or Mouse-tail, for that its Dia­dromes, or differences, between greatest and least expansion, do continually be­come less and less, even as it happens in Pendulums, once removed from the perpen­dicular, which continue their motion for a long time, after the hand is from them that first set them awork. At least this e­bullition of the blood in the heart, seems not a little to contribute to the continuati­on and strengthening of this pulsive moti­on. In contemplation of this Orgasmus, or fury, as I may call it, in the blood issuing out of the lungs, and now to be distribu­ted into all parts of the body Nature con­trived [Page 55] the Arteries with thick and double coats, the better to contain it: whereas the veins designed for the carrying it back a­gain to the heart, at what time the blood is very much cooled and tamed, are only made of single membranes, as being suffi­cient now to hold it. And this is all the difference between Arterial and Venal blood.

5. It seems of all other Opinions the most probable, that the blood, when arri­ved at the extremities of the smallest Ar­teries, is there shed upon the habit of the body, in the belly, or fleshy part of every Muscle; each Muscle having the proporti­on, or likeness, of one of the quarters, or Acetabula in an Orange, or a Lemon; up­on the compression of which, either by local or tonical motion, it is not hard to conceive, how the blood is again forced into the mouths of the veins; and after the same manner has every Muscle its parti­cular membrane. And thus we find that blood issues forth, upon pricking the flesh, in any place; although it cannot be imagi­ned, we should always prick a vein or Arte­ry: or we must conclude, there is nothing [Page 56] else in flesh, but a multitude of capillar veins and arteries, which were absurd to be asserted.

6. To make short: Life it self is but a continuation of this vigorous fermentation of the blood, which is so long maintained, as the Mass of blood is kept hot, and circu­lating through the veins and arteries; and if done by those means, and in that manner, which is suitable to Nature, so long the bo­dy is in perfect health. If it be too violent­ly fermented, or moved, it does, in gene­ral, become the cause of Fevers, and other acute diseases: as contrariwise, if the fer­mentation be too weak, from thence all chronical diseases take their original: and that particularly, according to the several irregularities that may happen, either in excess, or defect, in this fermentation and circular motion of the blood. We descend not now to particulars, the most we aim at in this Treatise, being but a general me­thod, either of preventing or curing disea­ses, after a way not yet treated of.

7. Since the discovery of the circulation of the blood, it has been the Opinion of many great Assertous of it, that where the [Page 57] indication is of letting blood, it matters not out of what vein it be taken, provi­ded, so many ounces be let out, as the dis­ease requires. And this their Assertion is made probable, by many arguments alledg­ed by them for that purpose; and but for the tonical motion of the habit of our bo­dies, would be as great a truth, as any is in Physick. But the tonical motion of the parts once admitted, We must likewise grant, that those parts will empty them­selves first, that lie nearest to the incision; as well, for that there is less strength re­quired to force any liquor to a shorter than a longer distance: as also, because the more remote parts, or Muscles, do exercise a kind of Antipraxia, or Contranitency, and so become of mutual impediment one to the other: whereas the nearer parts, do almost immediately discharge themselves upon the Orifice, or incision.

8. From this tonical motion of the whole body, it happens, that any particular part is sometimes preternaturally swelled, either from a stroak, the application of cupping-glasses, or generally any other cause, which may weaken the tone of the part; for in [Page 58] such case, the heart continuing its motion, for the distribution of the Mass of humors, it is very easie to conceive, that more of them will pass into that part, where least resistance is made, than otherwise would have happened, had the part continued in its natural tone and vigour.

9. From hence likewise the reason is to be sought, how it happens in letting blood, that so large a quantity should in so small a time, issue out at the incision made in one vein, and that perhaps none of the largest. For if we duly consider, how quickly a man may bleed to death, by the opening (for instance) of a vein in his arm; we must conclude, that the blood passes not much faster through the heart, than it does at the same time out at the O­rifice in his arm; and that consequently, there is but little blood received, during this evacuation, into the rest of the body, which doth then by its tone discharge it self (into the great vein) of its Plethora, or superfluous blood▪ which returning a­gain from the heart, toward the habit, the greatest part takes its way to the part, where the incision was made, it finding [Page 59] there no other opposition, than what it has while it is travasated from the arteries into the veins, through the smallness of their mouths, which yet is in part recompenced by the multitude of them. Now if it be agreed on, that in half an hour a man may bleed to death, or thereabout, if a vein in the arm be kept open: and that there will, in such case, be about one half of his blood let out, computing what is likewise con­tained in the capillar vessels, and what re­mains in the habit of the body, it will fol­low, either that the whole Mass is compleat­ly circulated twenty four times in twenty four hours, or a natural day. Which seems a little too often, or that the blood circu­lates much faster, while a vein is breathing, than at other times, which is not improba­ble; or that a man may continue bleeding longer than half an hour, which is not so likely: or that there is not in such case of bleeding to death, one full half of the Mass let out: All which may deserve a more exact scrutiny, but must now be left to be decided by the experiments of such, as are conversant in the dissection of live Animals.

[Page 60]10. It is frequently seen in horses, that upon long and much labour, they lose the sight of their eyes; nay, I have known some horses that have lost one or both eyes, with one days over-straining, either by draught, or course, and so became blinde of a sudden. And then we commonly say, they have drawn their eyes out: But how the eyes should suffer, or what part they take in the labour, or violent exercise of the body, is not so easily made out, unless by this tonical motion of the body, which now becomes much strengthened by the vi­olent local motion, either in drawing, or running, whereby the Muscles of the whole body are much more compressed, than in their natural state of rest, and con­sequently, do not only not admit of the u­sual quantity of blood and humours, due to them by circulation; but by their vio­lent and frequent contraction, do return them back in much a larger proportion, than they now receive them; whereupon the lungs become over-charged, which causes frequent breathing, and makes the pulse quicker and stronger than formerly, distends the great vein and artery, with a [Page 61] greater quantity of blood, than is usuall: Whereupon the Artery, by its pulse, and tone endeavours to discharge it self upon the habit of the body, which not recei­ving it in its due and accustomed proporti­on, the blood does in a more than a usu­al manner, fill the vessels of the eyes (and other weak parts) and either by dissenti­on, compression, or extravasation of blood, or other humor, the order and disposition of the parts of the eyes becomes so confu­sed and disturbed, that no wonder if blind­ness immediately, or soon after, do ensue. Now 'tis manifest from hence, that where the body of an horse is clean, that is to say, not so full of humors; and where blood abounds not over-much, this accident shall not easily happen. And here we are to ob­serve, that though the native tone of the eye do rather exceed that of the other parts, than come short of it, yet it is not sufficient to resist this influx, when the tone of the other parts is so much streng­thened by the violent local motions of the body.

11. If we a little reflect upon the man­ner of the Circulation of the Blood, and [Page 62] how by very modern discovery, the Chyle is first mingled with the blood, in the axil­lary or subclavial veins, from whence it passes by the right Ventricle of the heart, through the lungs, into the left Ventricle; from thence to be distributed into the whole body: One thing very remarkable will arise to our observation; namely, that what part of the blood is sent toward the head by the carotides or arteries of the neck, flows thither very crude, and accompanied with all its excrements, it having not yet received or suffered any depuration, or al­teration, from the Reins or Spleen, like that which passes into almost all other, e­specially the lower parts of the body (though indeed it seems not to be cleansed of the gall, till it returns home again through the liver.) Now though Natures purpose herein be very obscure, that the blood thus impure, should be designed for the service of the most Noble part, yet, that so it is, will farther appear, by the se­veral Emunctories (or sinks) wherewith the head is in a particular manner provided, as the ears, eyes, nose, palat; every of which, discharge the brain of a several excrement, [Page 63] and that no longer useful to the body, ex­cept what is secerned by the palat, which is for the most part again returned to the stomack: for the better separating of which, Nature has industriously placed a­bout the head, so many of those serous vessels, called the Ductus Salivares, which seem here to perform the same Office, to that part of the blood sent to the head, which the Reins do execute, to the re­maining Mass. Hence no wonder it is; if excessive drinking do so much weaken the brain, cause Catarrhs (which is nothing but an over-flowing of the Ductus Salivares) weaken all the faculties of the Soul and senses, and at length, enervate the whole body, although, at the same time, the Reins do their duty indifferently well; and this especially, if the native tone of the brain be weak, it being then so much the less able to discharge it self of such super­fluous excrements. This may be said in general, that the blood is thus sent to the brain, before depuration, in regard of its publick Office, that the same may there be farther elaborated, as shall best suit with its service in that Noble part. Thus [Page 64] much, by way of an useful digression, may suffice, concerning tonical motion, and some considerable circumstances of it; which as well for the assistance it gives the heart, in the circulation of the blood, as for the ma­ny useful indications from thence arising, in the Doctrine of Phlebotomy, was most properly to be handled in this Chapter of Sanguification.

12. And now I do not much doubt, but whoever shall have carefully perused what has been lately said concerning Sanguifica­tion, and the use of the lungs; will as rea­dily conclude with me, that the lungs do bear a very principal part in the work of Sanguification, for in them the Chyle is perfectly mingled with the blood; in them one half part of the circulation is perform­ed; and in them the blood seems to free it self, first of all, from any excrement: to wit, a fuliginous, or rather a vaporous wa­try superfluity (which passeth out together with our breath.) And this seems the first and chiefest part of Sanguification. The second, is a farther elaborating the Mass of blood in the arteries, which is performed by the pulsive motion of the heart. The [Page 65] third and last part, is the depuration of the blood, whereby its superfluous excrements are separated from it: and this is perform­ed by the rest of the bowels thus: by pas­sing through the Reins, it is dreined of its serous parts: Another excrement it seems to leave behind it in the Spleen, though of what kind, is not yet well determined among the modern Physitians: But on all sides it is concluded, that while it passe [...] through the liver, as through a Streiner, i [...] is there purged of choler, which in mos [...] Animals is collected in a little bladder, o [...] Cistis; from whence it is transmitted to th [...] Intestines, where it becomes a kind of na­tural Clyster, and provokes to the excer­ning the excrements of the first ways, as they use to term them. And this is what lay in our way, to say at present, concerning Sanguification.

interN. 1.HAving hitherto shewed what part the air acts in all fermentati­ons, and that in respect of its tone and temper: Viz. its difference of rarity, and density, and of heat and cold; and that in general only: not considering what other dispositions of the Air may make it apt to promote or retard the motion of fermenta­tion; whereby it may also powerfully ope­rate, to the continuation or destruction of mixt bodies: as not so directly serving for the illustration of the Subject, we princi­pally intend in this discourse. Having far­ther made it probable, that the work of our stomacks, upon our Aliments, as also, [Page 67] that Sanguification it self, is a kind of fer­mentation. And lastly, having asserted the publick Office of the lungs, together with the use of breathing, as well in promoting the circulation, as elaborating of the blood. And having likewise said something of the tonical motion of the body; and all this, after a manner, somewhat different from what has been hitherto received, and taught in the Schools. It remains, that from these Physiological speculations, we proceed to raise some medicinal conclusions and contrivances, very useful for the cure, as well as prevention of sundry diseases.

2. But first it will be necessary, to premise, that the Atmosphere, wherein we breath and live, is heavy or ponderous, and presses more or less, upon all bodies in it; and upon all sides exposed to it; and that especially, according to its difference of ra­rity and density. So that upon the tops of very high hills, and in bright weather, the Atmosphere will lie lighter upon us; and all other bodies than the same, will in thick weather, and in deep valleys; and conse­quently, that we move with more difficulty when the air is thick, and with more ease [Page 68] when the same is thinner; which is as much as to say, that the resistance of the Medium is proportionable to its measure of rarity and density. All which we now take for granted, and shall spare our selves the pains of proving, as what has been already sufficiently made out by several learned men in this our Age: from whose writings such as doubt, may receive very ample satisfa­ction. And we shall only conclude, that if all motion, be easiest performed in the thin­nest air, then in such an air, we shall breath freer, digest our meat better, and be less tired with wa [...]king, or working, than in a thicker air: and consequently, perform all the functions of life better, as is indeed manifest, even to experience it self. (which yet is wont, for the most part, to take no­tice but of the more gross observables) for who almost is there, of so happy a constitu­tion, that during health it self, and in the prime of his years, is not in some measure affected by the alteration of the weather, and by the change of the air? for, as for such as are sick, the very moments of life and death, do seem to depend upon this change: and such as are Valetudinary per­sons, [Page 69] commonly find, to their great grief, that their own bodies, may indifferently well supply the want of a weather-glass, in admonishing them, not only of the changes of the weather, but of the seasons of the year also. So very considerable is this alte­ration of the air to all mixed bodies, espe­cially Animals, and among them, to men more particularly, as being less armed a­gainst the injuries of the air, and among men most of all, to such as are infirm; as hath been said.

3. Now if the Natural and Vital Functions are better and easier performed in a purer air, than in a courser; no wonder, if upon changing the worse for the better air, many (especially Chronical) diseases, do by degrees from thence, receive a cure: which were before invincible, by other remedies: or must have been patiently endured, till the alteration of the season of the year, intro­duce that change in the air, (as to its tone and temper) which is sufficient so to rectifie the motion of the humours in our bodies, as at length to overcome the distemper. Which might possibly have sooner been ob­tained, by a seasonable removal into a whole­somer, [Page 70] warmer, or drier Region. But it is much more remarkable, that not only the changing a bad air for a better, is available in such cases; but much more the often changing of the air, though sometime for a worse, which is not only confirmed by experience, but likewise by the Authority of C. Celsus, who strictly injoyns it, and adds this as a reason, that if a man reside in so good an air, that he knows not where to remove to a better, yet it will be profita­ble for him to remove, and that often; for in case of sickness, that may justly be e­steemed the worst air, as to the concern­ment of the Patient, in which the disease took its beginning. The reason (in gross) why changing the air at all, should cure dis­eases, may be this; that the body of man is capable of enduring a greater latitude, either in the tone or temper of the air, than what the disease thus curable can consist with; and perhaps no other Animal is able to endure that variety of Climes, that a man may indifferently enjoy himself in. And thus men are found to inhabit in all parts almost of the Inhabitable World, whereas other Animals are proper to this or that [Page 71] particular Region, and will either die, if transported into other places, or at least lose much of their vigour, and not gene­rate. The same is also observable in plants. 'Tis said, that Lice bred on this side the Line, (or Aequator) will immediately all die on the other side the Line: So that it follows, the Ptherasis, or Lowsie disease, will be speedily cured by such a change of the air or Clime: and all, or most other diseases, do seem to bear some Analogy in their existence, to the life of that despica­ble little Animal. But that the often chan­ging the air, is so much a Nobler Remedy, than that of removing once for all into the best air: The reason is surely this, that first, in the finer air, the motion of Fermen­tation of the humors, and juices of our bo­dies, is better performed, and somewhat accelerated; and again, a little retarded, by a speedy remove into a grosser air, whereby the humors are, as it were, knead­ed or carded; and the disease at every such change, receives a notable shake, which seems to be much more sensible (if I may so say) of every such impression, than our bodies are. And this often changing the air, [Page 72] does well resemble the many stroaks, which are necessary to fall the sturdier Oak, while one or two, though very considerable ones, are not sufficient to bring him to the ground. I should therefore from hence conclude, that if once changing the air, do not in some reasonable time give assurance of a cure, that then we doubt not, with the Judicious Celsus, to change, as often as shall seem convenient, which surely will, (other helps not neglected) at length (pro­vided the disease be curable) put an end to, and wholly eradicate the distemper, be it almost what it may be.

4. But it will not be amiss, to be a lit­tle more particular, in shewing, after what manner the air works upon our bodies, and affects it with its several alterations, and dif­ferences of rarity or density. And first, I think it wi [...]l be granted by most men, and might be clearly proved by several experi­ments, that there is a certain quantity of air in all liquors, insensibly dispersed in very minute parts, through the whole Mass of them, which small particles do actually symbolize with the Medium; and will, by contracting or dilating themselves, cause [Page 73] the liquor wherein they reside, to take up sometimes more, and sometimes less room: as will be manifest to him, that shall fill a large glass bottle, of about a pottle or more, with water, till it rise two or three inches in the neck, which will need to be very slender, and somewhat long, and it will soon appear, that the water shall sometimes rise, and at other times fall, almost after the manner of ordinary Weather-glasses: as will be much more manifest, if it be for a while set neer the fire, so as to be a little warmed by it. Now the humors and jui­ces of our bodies, have likewise the [...]r cer­tain proportion of air in them, and that in a far greater measure, than common wa­ter, which seems of all other liquors to con­tain the least (as is probable from the small inclination it has to be fermented) and therefore it seems to follow, that upon all changes in the Air, or Medium, the juices of our bodies are affected: (even after the same manner, as has been said of common water) and that according to the alterati­ons of the Weather, of day and night, and of the seasons of the year. Which al­terations, or changes, in any one particular [Page 74] place, have a kind of orderly method of succeeding one another, but much diffe­rent from that of another place or Region, which, though it have the like alterations of Weather, Seasons, &c. yet the order or method of this variety, is as it were, of an­other Scale from that of the former. And the differences of heat and cold, density and rarity in the Medium, are either greater or smaller, than those of the former: whereby the body removed from the place of its former aboad, to another, is affect­ed with the varieties aforesaid, after ano­ther manner than what was usual to it. Whereby the face (if I may so say) or complexion of the humors and juices in the body, will be much altered and chan­ged from what it lately was: and conse­quently, the Morbose Character very much defaced, if not wholly obliterated. Which effect will in all probability more certainly succeed upon often, than upon once change­ing the air, as has been already sufficiently evinced, both from reason and experi­ence.

5. Of all changes of the air, that is commonly observed to be most effectual, for [Page 75] the cure of any distemper gotten abroad; which is made by removal from a forreign Country, to a mans own Native Soil, or the place of his birth, and first abode: which seems to be true (caeteris paribus) from hence, that the Aerious Particles, which originally go, as one principal ingre­dient to the making up of the body, were at first of the same tone exactly with that of the Medium: and it cannot be imagin­ed, but that upon any considerable re­moval, these Aery Particles must be more or less dilated, or contracted, than they formerly were, whereby the body will be preternaturally affected. Which though during the state of health, it be not cause sufficient, perhaps, to manifestly hinder any action of the body; yet in case of a dis­ease, it seems to be a notable relief to Na­ture, to be restored again to its Native con­stitution (as far as is possible) which is a kind of renewing, and no small refresh­ment to the body: from whence a Patient seldome fails of a relief, and very often finds a perfect cure, in several contumacious diseases.

6. I would not be so far misunder­stood: [Page 76] as if I asserted the alterations our bodies suffer from the Medium, to be ex­actly the same, in degree, with those of the Weather-glass; for that I think were hard­ly consistent with perfect health, as we find these alterations in most persons are: though in infirm bodies they are very mani­fest. But I suppose, by this time, it may be expected from me, that I give an ac­count of this difference, and say how it comes to pass, that the air in our bodies is not affected by the Medium exactly, after the manner of the Weather-glass, but in a less degree, where for the only reason I can think of, I shall assign the tone or to­nical motion of every body so often menti­oned; which being compressive of all the parts of our bodies, it very considerably checks and hinders that dilation of the hu­mors, by means of the rarified air, which would otherwise ensue upon the like affe­ction of the Medium: which compression, or resistance of the tone, or tonical motion of the body, may be very well illustrated from a bottle full of (nothing but) air, well stopt, and afterward exposed to the diffe­rences of heat and cold. In which case, it [Page 77] cannot be imagined, that the included air, is at all either dilated, or contracted: not the first, because there is no room for it to expand it self upon, nor yet the last, be­cause the sides of the Bottle are not apt to subside, without which, no sufficient rea­son can be given, why the air, upon exter­nal cold, should quit any part of the place it formerly replenished. And yet in some cases, the differences of heat and cold may be so great, as to prevail over the strength of an ordinary bottle, and break it, as has been often found by experience. But here we must observe, that though the sides of the bottle give no way at all to the air included, yet the tonical power of the body doth somewhat yield to such alterati­ons of the humors; and that more or less, according to its different strength in the body, of this or that individual. Nor doth this experiment of the Bottle suffici­ently conclude, but that, at least, the com­pression of the air in our bodies, ought to answer that of the Medium: and indeed, that it doth not, seems to proceed from the internal heat in the humors of Animals, (maintained, as is said in the Chapter of [Page 78] Sanguification) which is of power suffici­ent, not only to resist the compression of the tone, or tonical motion of the habit of the body, but that of the medium also. And should the contrary happen, death would inevitably ensue.

7. It may be farther noted, that all bodies (whether men, or other Animals) are not equally affected with the same change or alteration in the Medium; but, as hath been said, proportionably to the strength of the tonical power of each bo­dy. And thus it happens, that a person of a Robust Constitution, and habit of body, (whether such naturally, or acquired by much travel and labour) will with less trouble and hazard of his health, endure any notable alteration, or change of Wea­ther or Soil, than another of a finer Tex­ture and composure; and whose tone con­sequently is not so resistive of the impressi­ons from without, as that of the former. And thus it is easie to conceive, why a per­son inhabiting neer either of the Poles of the Earth, and removed to, or neer the E­quator: or the contrariwise, will find the temper of that Clime more troublesome [Page 79] and offensive to his health, than he shall, that from the middle temperate Region, shall transfer himself to either of the ex­tremes. And no doubt, the less the diffe­rence is, the easier and sooner shall a mans Nature be brought to comply with it. And thus we observe, that Spaniards and Portu­gezes, do with less danger, travel and trade into the more Southern Regions of the world, than Northern men can do, who are commonly not otherwise seasoned, than by some dangerous Calenture, Flux or Spasm, or other deplorable disease, where­by much, the greater part of them, are com­monly destroyed. All which diseases are no other, than the effects the Medium hath upon the Air imprisoned in our bodies; which if it finds the humors easily dispo­sed to a farther degree of fermentation, than what is consistent with health, it pro­duces a Fever or Calenture in some bodies; in others, a dangerous Flux: and in some most violent Spasmes, upon the forcible di­latation either of the Air in the nervous parts, or of that, which may possibly be, in the spaces between the Muscles.

8. From hence probably it is, that [Page 80] the fruits of those hotter Countryes are so dangerous, especially to strangers; for that they are no sooner received into the body, but they are straightways very vio­lently fermented (and after the same man­ner ferment the juices of the body, to the disordering of the whole frame) in so much, that the juice of some plants, is ac­counted a deadly poyson, as that of the Root of Yucca (while the solider parts are made into a kind of wholesome bread) and possibly, for no other venomous quality, than its over-active fermentation, whereby it not only disturbs, but destroys the Oe­conomy of the body. All which, and much more of this kind, that might be produ­ced, seems in great part to depend upon the fineness, or rarity of the Medium, which lying lighter on liquors, and other bodies thus fermented, suffers them more easily, and more violently, to expand them­selves, than, for the most part, is suitable with the health of such as eat them, espe­cially in any considerable quantity.

9. And now from what hath hitherto been said, it may seem exceeding probable, that the Air doth considerably alter, and [Page 81] dispose the humors of our bodies, especial­ly upon changing one Clime for another; and that our bodies do, more or less, sympa­thize with the present tone and temper of the Medium; whereby it is not only freed from several distempers, but may also ve­ry often be thereby variously disaffected, and cast into divers dangerous diseases. But yet, how useful soever the changing of the Air may be, for the cure of any infir­mity: we find it stands with the conveni­ence but of very few, to make such re­movals; for that they cannot well dispense, with the leaving their Families or Relati­ons, together with other their familiar af­fairs, or imployments. Besides, Physitians are not apt to advise their Patients to it, till they have first, in vain, imployed most other remedies in the cure of them; where­by commonly the oportunity is lost, and the sick person deprived of that benefit he might, in all probability, have received, up­on a more seasonable removal. Besides, ma­ny times, it would be necessary, not only to remove to some neighbouring place, or other, but even to take a journey of some hundreds of miles, which cannot be per­formed [Page 82] by the sick, but with great diffi­culty. So that what through one impedi­ment, or other, the thing happens to be but rarely put in practise; and so Noble a Re­medy, is not only neglected, but in a man­ner brought into disesteem with some, for want of more frequent examples of the great use of it; while they cannot give themselves a satisfactory account, how such a change of the Air should so considerably work upon our bodies.

10. Now to the end we may not want the help of so generous a remedy; and for the better avoiding the fore-mentioned in­conveniences in the use of it. I hold it a matter of no small compendium, in this place, briefly to set down, and shew the manner of a certain contrivance, how any person may receive the benefit he may ex­pect, upon removal from his abode, to any other place (with intent to change the air) and that almost indifferently at any season of the year, without so much as remo­ving out of his own house, or neglecting any occasions whatsoever. First therefore, in some fit place neer, or adjoyning to your house, erect a convenient Room, of about [Page 83] some twelve or fourteen foot square, or of what size you please, either bigger or smal­ler than the former, and let it be exactly well cieled, or vaulted over head, and well paved; or otherwise so floared at bottom, that the air may not have any vent, to get either out, or in, nor yet through the walls, which it is requisite should be of brick or stone, and well plaister'd on the inside; and let the windows be likewise so contri­ved, that no air may pass in or out that way, which the easier to prevent, and that they may be also the stronger, and less apt to crack, they ought not to be very big, nor many. The door must be likewise so contrived, that it may shut into its frame so exactly, that when it is made fast, there may not be the least passage left for the air to get in or out of the foresaid Chamber. The particular manner and contrivance of doing all which, I do not here set down, for that I doubt not, but there are ingenious Masons and Joyners, that will much exceed any directions, that I can be able to give them. Your Air-Chamber being thus made, you must farther provide your self with a very large pair of Organ Bellows, which [Page 84] must be placed in some convenient part of the Room, where by the help of a Skrew, the Nose of them may be exactly joyned to a Copper Pipe, whose other end must pass through the wall of the Room, and have a value, opening outward, exactly fitted to it, as is usual in Water Engines: and if the said Value be placed in water, it will do much better. This Brazen Pipe must likewise have another Value to open inward, and both so contrived, that either of them may be set open at any time, or ta­ken off, while the other is imployed. The Bellows being thus fitted, and the door and windows close shut, you may at pleasure either fill the Chamber with Air, by force­ing in what quantity you please, till there be twice or thrice as much as there was at first, ti [...]l the same be as thick as is requi­site. You may likewise discharge the Cham­ber of one third, one half, or more of the air it had at first in it, till you have on the contrary, brought what remains, to that degree of Tenuity (or thinness) is requi­red, and this by the help of the Bellows; which if the air be to be forced out, must lie with their moveable part upwards; and [Page 85] the innermost Value of the Brazen Pipe, before mentioned, must either be taken off, or kept constantly open: but if air is to be forced into the Chamber, then the Bel­lows will need to be turned the wrong side upward; and the outward Value of the Brass Pipe must be taken off, or kept o­pen, and the innermost Value suffered a­lone to play. In which cases, working gently with the Bellows, you may either charge, or discharge (as I may say) the Air-Chamber at your pleasure, and conse­quently, obtain an Air in it, of what rarity or density you please. The measure of which variety, that you may the more ex­actly take an account of (and that there may be very little or no mistake in the use of this Chamber) it will be absolutely ne­cessary, to have constantly with you, a large Weather-glass: And you may likewise have a Tub of glass, of some forty inches long, filled with Quick-silver, and in­verted into a little Earthen or Wooden Vessel, half filled, with a quantity of the same material, after the manner of the Torricellian experiment; and these are to serve you for Registers: for by the ascent, [Page 86] and descent of the Water, in the Weather-glass, will be noted to you, by the de­grees, on the neck of the Glass, in what prop [...]rtion you have either rarified or con­densed the Air within the Room: and you may by help of it, rectifie the tone of the Air, to what degree is requisite, or injoyn­ed. The use of the Quick silver Tub, is the very same, but will not give so exact an account, of every small difference, as the former, by reason of the small quanti­ty of Air contained in it: but yet will not want its use in other experiments, not re­lating to Physick, which I shall not here touch upon, as too remote from what we here handle. Such therefore, as imploy this contrivance, only in Relation to their Health, may content themselves with a Weather-glass, which will prove much an exacter Register, than the Quick-silver Tub, as hath been already shewed.

11. As to the particular application of the use of the newly described Domici­lium, or Air-Chamber, 'twill not be amiss to repeat, what we before asserted in the precedent Chapter; namely, that as health it self, is maintained by a due and suitable [Page 87] fermentation of the humors in our bodies, and that within a certain latitude. So, if the irregularity of the said motion, or fermen­tation, be great enough, to become the cause of the manifest abolition, or weaken­ing only, of any action of our bodies, the party so affected, is said to be sick, or diseased: and as all diseases may be divided into acute, whereto are those of short continuance to be referred (though they are not usually termed Acute, taking the word more strictly) and Chronical affe­ctions: or else (which comes to the same thing) they may properly enough be divi­ded into diseases, participating of heat, or of cold. The former of which we have al­ready defined, to depend upon such an ir­regular fermentation of the blood, and Mass of humors, wherein the same are more violently moved, than is consistent with health: of which kind are all continu­al and intermittent Fevers, all Inflammati­ons, most Fluxes, and several other distem­pers: and contrariwise, all Chronical, or cold affections, seem to depend upon such an irregularity of the foresaid Fermentati­on, whereby the humors are not so suffici­ently [Page 88] moved, and agitated, as is requisite to health; of which kind are the Scurvey, the Rickets, all Dropsies, some Fluxes, most affections of the Spleen, and probably the Gout, and other Arthritical distempers. Now the method of using this Domicil, or Air-Chamber, in general, will be this, that where the disease seems to depend upon a deficient Fermentation of the humors, in such case, the Patient (being put into the said Chamber, and the door close shut) shall, by degrees, discharge the same, or force the air out; till having considerably alter'd the tone, and rarified what re­mains, he still finds himself to breath free­ly, or at least with no great difficulty; at what time he may observe, how low the water is descended in his Register, or Wea­ther-glass, which will shew him how far he may safely, at another time, discharge the air, without danger of Cramping; which uses to ensue, if the air be too ex­ceedingly rarified. On the other side, if the disease be Acute, and seem to depend upon the too violent Fermentation of the humors, then it is necessary the Chamber be well charged with air, to what degree [Page 89] of Toleration shall seem convenient. And here we are principally to provide, that no difficulty of breathing ensue, which oftner happens in this practise of condensed, than attenuated air. Now the term of the Pa­tients continuance in the Chamber, at one time, is to be defined in Chronical diseases, as well from his own occasions, as other cir­cumstances; and generally two, three, or more hours, may seem sufficient, and that especially in the morning, when the use of other Remedies are found most conducible. But in acute diseases, it should seem neces­sary, that the Patient continued in the said Chamber, during the whole course of the disease, and that the tone of the air be pru­dently altered, after the directions of some able Physitians, according as the times of the disease shall seem to require; especially in intermittent Fevers, where the time of the whole Paroxisme must be spent in the Chamber, and the cold fit requires to be treated as a cold disease, with rarifying the air, as the hot fit, by condensing it, which must be carefully observed. Now though there may be many diseases, as the Stone, the French Pox, and some other, [Page 90] which do not depend so immediately, upon the aforesaid irregularities of the Fermen­tation of the humors; yet I should not doubt, even in these, to commend the use of this Domicil, or Air-Chamber: for that while Nature is thereby much strengthened in all her Natural Functions, it must needs follow, that she will from hence, at least, be enabled the better to endure the conflict with those diseases, if, at last, she do not wholly get the better of them. It will farther be necessary here to add, that in maligne diseases, and where we require an amendment of the insensible transpiration; we are, as in cold diseases, to rarifie, and not condense the air in the Domicil, where the Indication is rather preservative, than curative, as Physitians use to speak.

12. To say something of the use of this contrivance, in time of health, we shall only propose it, as a good expedient to help digestion, and especially insensible transpi­ration, and facilitate breathing and expe­ctoration; and consequently, as of excel­lent use, for prevention of most affections of the lungs, where they are feared; and that generally, what ever the benefits of [Page 91] changing the air, are, may be reasonably ex­pected from the use of this Domicil; and that after a more certain regular way, than without it, for that by the means of it, a person may serve himself with such air, as were not otherwise to be found, but on the top of the Pike of Teneriff, or some other very high Mountain: nay, if it were con­venient, as perhaps it may in some very con­tumacious affections, he may rarifie the air to a far higher degree, and make it such, as is not again to be found upon the face of the whole inhabitable world. But as well in sickness, as in health, those great excesses are not to be ventured upon, but by de­grees. The use of this Domicil may be far­ther extended, for preventing the inconve­nience which may ensue, upon any great change of air, by travelling into forreign Countryes; whereby a person may at plea­sure reduce the tone of the air, to that of his own Soil or Climate: and probably, if the same might be made use of aboard Ships, it would (with the additional contri­vance of a Chair, or Bed, hung after the manner of a Sea-Compass) prevent that [Page 92] very trouble affection whereto fresh men are so subject, called Sea-sickness; and con­sequently, become very serviceable to such, whose imployments ingage them to under­take Voyages into very remote parts, and there to reside, far from their own Coun­tryes. There may, I doubt not, several o­ther considerable conclusions be performed, by means of this contrivance: As also, that the thing it self is very capable of good improvement, as to the projection of it, far beyond that described by us. All which, together with what hath been already said, and undertaken by us, on the behalf of it. We leave for farther discovery, and confir­mation, to practise and experience.

13. Among the improvements which this contrivance of an Air-chamber is probably capable of, it is in my judgement none of the least that may be obtained, by joyning the practise of S. Sanctorius, in his Medicina Statica, to this of ours. For as the promo­tion of the transpiration by the habit of the body (than which, nothing conduces more to the preservation of health, and prevention of diseases) is one of the most [Page 93] considerable among those many benefits we promise our selves by it: So, if we shall have, as Sanctorius directs, a Statera Roma­na, in our Air-chamber, it will be of very great consequence, for ascertaining the Me­thodical use of it, whereby it will become less subject to guess or hazard. For as the Weather-glass, before-mentioned, will dis­cover to us, the degrees of rarity and den­sity, introduced in the inclosed air: So the Balance, will with the same exactness in­form us, at what rate this Diaphoretical transpiration, is either improved or abated: and at the same time give us the true weight (in Ounces and Drachmes) of those insensible Effluvia, which continually pass that way. For the Patient, weighing him­self (for instance) first at seven of the clock in the morning, and again at nine or ten (having first exonerated himself) and ab­staining from meat and drink, in the mean time; shall thereby perceive how much (by weight) of his aliment, or rather of the unprofitable part thereof, in those two or three hours, passed insensibly through the pores of his body. Let him again re­peat the same experiment, the day follow­ing, [Page 94] with the same circumstances, in the Air-chamber: and he will not be a little surprized, to find half so much more, and perhaps, twice the quantity evacuated, af­ter the same insensible manner (or è contra) and that in such proportion, as he shall have suffered more, or less, of the included air, to have passed into the circumstant Me­dium, (or è contra) of what proportion the Weather-glass, as a faithful Register, shall give him a very particular account. I will not farther inlarge, upon this addi­tional practise, of the Scale or Balance: much less add any thing of the use of in­sensible Transpiration, least I might offend such, as are better versed in Statical Experiments; by the unprofitable repetiti­on, of what they are already so well ac­quainted with: or by giving an ill account of a book I have but once read over, and that neer twenty years since, deprive others of that solid benefit they may receive, by perusal of the above-commended Treatise of Sanctorius.

14. As this contrivance of the air-chamber, is best fitted for the improvement of health, and the abolishing such Morbose Chara­cters, [Page 95] as depend upon the over-slow, or too nimble fermentation of the Humors. So it were easie to project, great Vessels, after the manner of Cupping-glasses, some capa­ble to receive the whole Thighs, others fit­ted for the Arms: whereby we may at pleasure, (as the seat of some particular diseases shall direct) make such powerful revulsions, as shall not only be sufficient, to charm, as it were, and dispose of such hu­mors, as Physitians call Turgid, and Motu Peccantes: but even discharge particular parts of such humors, as have seated them­selves there already; and may, besides that of Cupping-glasses, very fitly supply the place of the strongest Ligatures. Which practise, as it may be very available, in most affections of the head: In inflammations, or other tumors or charges, of particular parts: So (not having yet had sufficient op­portunity to confirm this my Opinion, by the frequent use of it) I shall content my self at present with having done little more, than named it only.

15. I shall add farther, that the use of this Air-chamber, may in some cases, but after a weaker and more uncertain manner, [Page 96] be supplied by a long-setting Swing, which is found to be a very agreeable exercise, by most people that have used it: if their bo­dies have not been very impure, or first duly prepared. And by it many persons, affected with Chronical distempers, taking their original from a deficient fermentation, have found benefit. For, motion con­ducing so much (as has been said) to the exciting of all fermentation, (which is visi­ble in Syrups, and other juices of Vegeta­bles shaken, and as a proof of it, that Bran­dee Wine, is accounted the best, that upon shaking bubbles and works most) no won­der if the seasonable continuance of this moderate, reciprocal motion of the Swing, do by degrees, (though not so suddenly as in the fore-mentioned instances of Syrups, &c. because the humors in our bodies lie not so loosely as they, in Vessels of glass or stone) produce the same effect, we ob­serve without, in other liquors. Nor is the fermentation (or call it concoction) of the humors in their Vessels, hereby only advanced: But likewise the distribution of the first, and second ways, (if I may so call them) is very much promoted: For [Page 97] still, as the body is carried forward, so of ten are the Abdominal Muscles, gently and equally compressed, whereby the chyle is the more nimbly pretended from the Inte­stines forward, to mingle with blood. And again, upon the recess of the body, the Abdomen being less compressed, than if the body set still in the same scituation, is more dilated than usually, and consequently re­ceives the chyle flowing, more plentifully from the stomack into the Intestines. So that, if it come faster into the guts, and be driven faster out, it must of necessity follow, that the distribution thereof shall be more readily performed. Now, for what we lately called, the distribution of the se­cond ways, that seems by the use of the Swing, to be improved after this manner: while the body moves forward, as the fore­parts are more compressed by the Medium, so the back parts are less compressed (and thereby, as we may say, their tone weaken­ed) whereby the habit doth not so forcibly resist the afflux of humors flowing to that part: as in its middle, natural, and quiet scituation. And thus reciprocally, first one part, and then the other, are somewhat bet­ter [Page 98] disposed, for the Reception of their ali­mentary juices, which I call the distribution of the second ways. And thus much may suffice to have said at present, concerning this matter. I shall only desire my Rea­der, that he will not be over precipitious, nor let the novelty of our attempt surprize him to a prejudice: and that he be first, for his own sake, well assured, he is Master of those principles, upon which this Fa­brick of ours (as upon so many goodly Pil­lars) stands erected, before he proceed to condemn us. But if upon the serious per­usal of this Treatise, by such whose Au­thentick Censure we most value and Reve­rence, we happen to be found light in our own Balance: We have at least to plead, that we have neither mispent much of our own, or their time in writing, or reading of it. And that though we failed, the de­sign was great and Honourable, and dire­cted to the benefit of mankind, which may in good part plead our excuse, and their good favour make out the rest.