<2Dreadful communications>2 BRITAIN has unveiled its plan for World Communications Year (WCY), a month after the year began and with the maximum of waffle and mini- mum of hard fact. As a result the valuable industrial opportunities for export created by WCY may be wasted. Ironically, the government's policy in another area, grants for foreign students in Britain, is likely to prove a handicap to whatever plans do come to fruition. In November 1981, the United Nations proclaimed 1983 World Communications Year. The official aim is for all countries to take a critical look at their own communi- cations policies and to help the developing nations improve theirs. Today 75 per cent of all telephones in the world are in fewer than 10 countries. Astute businessmen see WCY as a golden opportunity to sell more communications hardware to the Third World. A lynchpin of this policy is the offer of technical training to foreign telecom- munications engineers, because today's engineers are tomorrow's buyers. The government disclosed its plans for WCY on the last day of January simul- taneously in London and six cities, cour- tesy of British Telecom's #200 an hour Confravision service. But Patrick Jenkin, the Secretary of State for Industry, and Peter Benton, chairman of British Telecom Enterprises and deputy chaimnan of BT, showed themselves curiously ignorant of the fact that Britain has still not nominated a VIP for the WCY Committee of Honour. Forty-one heads of state have so far accepted; President Reagan is representing the US. Behind the scenes, apparently un- known to the minister and BT, there is a hunt on for a suitable candidate, probably Prince Philip or Prince Charles. Although the idea of WCY is over a year old and the year is now a month old, Britain has only just announced its six-man committee to represent the country's interests. This committee will include Kenneth Baker, Minister for Information Tech- nology, and Sir George Jefferson, chairman of BT. But no details are yet available of the cash to be made available, except that it "may be over #1 million". Patrick Jenkin admits that the campaign has begun in "low key" but says plans are afoot to let an unnamed African state have three GEC digital telephone exchanges at cut rate. The Department of Industry rec- ognises the value of training foreign en- gineers, as a long-term stimulus for sales of British-made equipment. Last year BT took 160 foreign students and firms such as Cable and Wireless took another 500. This year the BT number will rise to 250. But neither industry nor BT can afford to give free training so the bill must be paid by a foreign govemment or the International Telecommunication Union, which is based in Switzerland. This is why the tele- communications industry in the US is now finalising a scheme to use pooled money, with government administration, to pay for the training of foreign engineers. In Britain the DoI says it is "considering" ways of pulling in more students, and increasing grants to the ITU "five fold". A little dig- ging reveals an increase in the ITU grant from #20 000 to #100 000--barely enough to cover the student's fares to and from the United Kingdom. To make matters worse, foreign students no longer qualify for grants in the UK. So Britain may well be the last place engineers from the impoverished Third World come to train, or to buy telecommunications equipment. This is a classic case of saving pounds while losing millions. [] <2Transport models derailed>2 TODAY (Thursday) MPs will debate the future of the railways, and the contro- versial Serpell report. Sir David Serpell's report suggested axing 85 per cent of the railway network. The report claimed that the railways would then make a small profit. The Serpell report was published two weeks ago, two days after the Franks report. The Franks report cost #60 000 and stands a good chance of recovering some of that cost through sales of the report. The Serpell report cost #550 000. Quite what the tax- payer got for the extra money is not readily apparent. Most of the money that went into the Serpell report (#370 000) was paid to en- gineering consultants R. Travers Morgan. Travers Morgan produced the mathe- matical model of the railways which is the scientific foundation of the Serpell report. Yet this model is deeply flawed, as <1New>1 <1Scientist>1 revealed last week (27 January, p 220). It isn't just a matter of minor errors, such as including lines that have been torn up, or ending main lines in the middle of peat bogs. But at a more fundamental level the model predicts a profit on rail freight on the smallest railway network (of 2600 kilo- metres) when none of the major railway freight generators is linked to the network. The model's results are nonsensical. The 2600 kilometre network will plainly make a loss, probably of around #100 million a year. The consultants clearly expected too much from an over-generalised model, and as a result they produce results which lurch from the absurd to the ludicrous. But on a more fundamental level the fiasco illustrates the futility of trying to solve political decisions by mathematical models. The real political questions that MPs should ask in today's debate are how extensive should the railway network be? How much are we prepared to pay for it? No amount of mathematical modelling can produce the answers to these questions-- even at a cost of #550 000. In these days when money isn't worth what it was, it may not seem especially profligate to blow a few hundred thousands on transport modelling, but it is worth thinking about how else the government could have invested the money. The amount involved could have funded a dozen or so investgations of the social im- plications of the reduced rail network, or it could have kept open one of Serpell's threatened stations--Stratford-upon-Avon, for example--for a year. [] <2THIS WEEK>2 <2The Amazing Randi hoodwinks the spoonbenders>2 <2Jeremy Chefas>2 TWO EXTREMELY promising young psychics have exposed themselves as conjurors. The pair, Steven Shaw and Michael Edwards, astounded the parapsy- chological community with their abilities to bend metal, move objects across a table, link wooden rings, read sealed envelopes, and so on. But they are prestidigitators, not psychics--part of a plot orchestrated by James "The Amazing" Randi. Randi announced his coup last week. Berthold Schwarz, a psychiatrist and enthusiastic investigator of the paranormal, declared that this had "set parapsychology back 1 00 years". "No," Randi told <1New>1 <1Scientist,>1 "they're the ones who are stuck in the last century. We've brought parapsy- chology into 1983." The plan, codenamed Project Alpha, is preserved in a series of 388 documents. It began properly in 1979, when Sanford McDonnell, of McDonnell-Douglas aircraft, gave $500 000 to establish a labo- ratory of parapsychology at Washington University in st Louis, Missouri. Parapsy- chologists have always complained that they didn't get enough funding, Randi says, so this was an ideal opportunity to put them to the test. Randi got shaw and Edwards to offer their services to Dr Peter Phillips, director of physics at Washington University and director of the McDonnell Laboratory. At the same time he wrote to Phillips offering him advice that would help him avoid trickery (Phillips ignored this advice). The two most important items of Rand- i's advice were not to allow the subjects to run the tests, and not to allow capricious distractions. "But the boys went in and ran things their way," Randi said. They got rid of electronic monitoring equipment, including TV cameras and recorders, by complaining that these interfered with their powers and caused headaches. Just what the scientists who investigated Shaw and Edwards thought of them is hard to say. Randi says that "Phillips was fooled from the start". But Mark Shafer, who worked with Phillips until September last year, says that "the Mac [McDonnell] lab reports never made any conclusive claims" about the psychics. There have been publi- cations in the research journals of the Para- psychological Association, but Phillips told <1New Scientist>1 that these were "very cautiously worded". He does not think they constitute scientific claims. Randi asks when a statement becomes a scientific claim. He quoted a letter in which Phillips says "I continue to believe that Mike Edwards bent a key in my hand with- out ever touching it." The letter continues, "There is little point in my saying that in a scientific meeting, though I have. The required level of documentation is much higher," Phillips now says that "it was probably a trick". The effects that Shaw and Edwards produced were indeed baffling. But many were quite simply done. They managed to bend objects within sealed containers by simply opening the lids; the seal was not very effective and the tampering was not detected. Shaw produced images described as a woman's navel, a breast, a thigh, and Jesus, on an 8 mm movie film, This he did by spitting on the lens. They divined the contents of sealed envelopes by the simple expedient of open- ing the staples at the other end of the envelope. Randi says that none of these feats would have been possible if researchers had followed his advice. Phillips agrees and admits that when they did tighten up the protocols according to suggestions from Randi the effects could not be obtained. But, he told <1New Scientist,>1 "When a subject comes to us claiming these powers we take the claims at face value." Phillips says that "at first we try to set up a good rapport and explore the range of powers claimed. Then we tighten up the experiments." And that is when the effects began to vanish. "There was a point in there where I was 80 per cent sure that these guys were real." John Hasted, professor of physics at Birkbeck College, University of London, and an investigator of the paranormal, was very wary when told that Shaw and Edwards had been fakers "It's possible that it's true," he told <1New Sctentist>1 Asked about his conclusions from his own work he said "I accept that there are, shall we say, pulses of paranormal action which take the form of mini-acoustical shock waves. Some are electrical in origin, but even those I can't always explain." The participants all seem to think that the episode has been worthwhile. Randi says that it will persuade good investi- gators to take conjurors seriously. He praises Phillips and Shafer for coming round. Asked whether, having failed to get any positive results despite good funding, he would continue to investigate the para- normal, Phillips said, "that's up in the air. Maybe the phenomena are not there at all. Or they are but I'm not a very good person to bring out these effects, I don't know which is true." [] <2Physicists get rallying cry--and cash bait>2 PHYSICISTS, now is your chance to show that your subject is alive and well in British universities and polytechnics. The science and Engineering Research Council has doubled the money available for "small" or mainstream physics to #2 million. Half of the extra cash will be forth- coming only if projects of sufficient quality to take up the whole #2 million come in by the next deadline for grants on 1 April. The SERC's action, announced to 100 professors and heads of departments of physics at a meeting last Friday at Imperial College, London, is an attempt to stimulate some sense of direction among the majority of academic physicists who work in neither astronomy nor nuclear physics. Their grants at present are allocated by the physics subcommittee of the SERC's science board. The SERC also wants to identify and develop specific areas within physics, some involving collaboration with industry. And it wants students to complete PhD theses more quickly. Former physics committee chairman, Professor Jo Vinen reported a lack of vitality in physics last year. The new chair- man of the physics committee, Professor Michael Hart of Kings College, London, wants to see more representation of main- stream physics at the highest levels within the SERC--especially on the council itself. Ros Herman [] <2Psychiatrists shrink from not guilty verdicts on insane>2 Christopher Joyce, Washington DC AMERICA'S psychiatrists believe that too many defendants in important court cases in the US are escaping con- viction by claiming that they are insane--and psychiatrists are often too keen to help them. Last month the Ameri- can Psychiatric Association (APA) claimed that many of these people should be re- garded as "sociopaths" and should be con- victed. The move to get more defendants de- clared sane came as two suspected IRA gun-runners tried to convince an American court that they are insane. Colin and Ea- mon Meehan claimed that they were not guilty of trying to buy weapons in the US for the Provisional IRA because their in- ternment by the British in the 1970s drove them insane. The judge dismissed their claim. But at the heart of the new concern among American psychiatrists is the spec- tre of John Hinckley Jr. Last June Hinckley was found not guilty, by reason of insanity, of trying to assasinate President Reagan and of wounding three others in the at- tempt. Psychiatrists diagnosed Hinckley as suffering from a "schizotypal personality disorder", also known as ambulatory or borderline schizophrenia (Hinckley was subsequently committed to a mental hospital.) The verdict raised a furore over the role of courtroom psychiatry. Some critics, in- cluding the US government's attorney gen- eral, have called for an end to the insanity plea altogether. Last autumn, the APA set up a review panel and the new statement is the result. Psychiatrists do not feel at ease testifying in court today, according to one author of the report, Dr Loren Roth, who is director of the Law and Psychiatry Institute and Clinic at the University of Pittsburgh in Pennsylvania. "You can't really translate psychiatry into law and preserve science," Psychiatrists used to think that they could determine where free will began and ended and could decide objectively whether a defendant was sane or not. The APA now says psychiatrists should stick to describing a defendant's mental condition and his motivation at the time of a crime. "Determining whether a criminal de- fendant was legally insane is a matter for legal fact-finders, not for experts," says its report. Nine states of the US have recently ex- perimented with a different type of verdict. Criminals are being found "guilty but men- tally ill", rather than "not guilty but men- tally insane". This is similar to what hap- pens in British courts, but the APA is unimpressed. The APA says that many defendants can be described as "sociopaths". They do have control over their behaviour and should be held accountable for it. Only "serious" dis- orders should excuse the accused from be- ing found guilty. The APA also questions the current rule that the state must prove that a defendant is sane if he claims that he is insane. One idea is to switch this burden of proof so that the defendant must prove his insanity. Even more controversially, the APA wants changes in how violent offenders, who have been acquitted in court but com- mitted to mental institutions, are assessed. At present doctors must prove at regular intervals that such patients are still a danger to society. But modern anti-psychotic drugs tend to reduce "overt" signs of psychoses, the APA says. Too many violently insane patients are released because they appear cured. In Michigan, for example, 50 per cent of pa- tients who had been found not guilty by reason of insanity during the mid-1970's were discharged from mental hospital within 60 days. A special board of psychiatrists and other professionals should decide whether they should be released. And release should be conditional on con- tinued treatment. According to Roth, the APA's position is a move back to the M'Naghten rules--a doctrine established by the House of Lords after the case of Daniel M'Naghten in 1843. The M'Naghten rules are tougher than current US doctrine. For the accused to be declared insane, he must be so diseased "as to not know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong." [] <2Cut--price chart-toppers>2 THE BRITISH record business is already squabbling over its new computerised system for compiling the weekly charts of record sales. The new system uses bulky counter-top computer terminals, installed in a selection of shops, to monitor record sales. Within days of the launch of the new system, CBS, one of the biggest record com- panies, is being accused of trying to rig the charts by encouraging sales in the chart shops. CBS ran advertisements in the <1Daily>1 <1Star>1 which listed a selection of shops in which some new CBS records could be bought at very low prices. Gallup, the opinion poll company that runs the new chart, has noticed that an em- barrassingly high proportion of the listed shops are also chart shops. And one of the records, Men at Work's <1Down Under>1, is now top of the chart. But Gallup says it was not affected by the CBS promotion. <1Down Under>1 was a good record and hit material anyway. Gallup says that it compared sales in chart shops on and off the CBS list and found no difference. And it found that the <1Daily Star>1 advert had no effect whatsoever on record sales. The company intends to stick by its methods, despite the criticisms (<1New Scientist,>1 13 January, p 73). [] <2Fagan, Sutcliffe and utilitarian law>2 IN BRITAIN, Hinckley would not have been acquitted. The M'Naghten rules are still in force and the "not guilty by reason of insanity" plea succeeds only in about ten cases each year in British courts. Even then the defendant does not go free--he is confined in a mental hospi- tal until the Home secretary authorises his release. This does not mean that most mentally-ill offenders simply go to prison. The British "utilitarian" approach side- steps the thorny question of whether men- tal disease makes an offender "not guilty". Instead the mental state of the criminal is taken into account during the sentencing. The Mental Health Act of 1959 enables a judge, with the approval of two doctors, to impose a hospital order in place of a prison sentence. For instance, Michael Fagan, the Buckingham Palace intruder, was treated in hospital and re- leased recently on the approval of the Mental Health Review Tribunal. An apparently dangerous criminal may be hospitalised with a restriction stipu- lating that only the Home secretary can authorise his release. The Americans, by contrast, have, until the current backlash, attempted to expand the in- sanity defence, with its controversial "not guilty" judg- ment, in order to achieve the same compassionate aim of keeping the mentally-ill out of prison. Another defence is possible in British murder trials. The 1977 Homicide Act introduced the no- tion of diminished responsibility, which reduces a charge of murder to man- slaughter. The judge is free to impose any sentence and can send the convicted indi- vidual to prison or hospital. The recent plea of diminished re- sponsibility From Peter Sutcliffe, the so- called Yorkshire Ripper, was unsuccessful--to the great surprise of the examining psychiatrists. He was instead imprisoned for life. Gail Vines [] <2New dump for nuclear waste is planned>2 THE CENTRAL Electricity Generating Board wants to build a giant nuclear dump to store spent fuel from its nuclear ower stations. The dump will hold the highly-radioactive waste until it can be taken to British Nuclear Fuel's Sellafield works for reprocessing to extract uranium and plutonium. The dump is necessary because BBNFL's new THORP reprocessing plant, which should be in operation by 1990, will not be able to handle the volumes of waste that will be produced by Britain's power stations in the mid-1990s. The dump will be run by the CEGB and will require planning permission. No site has so far been proposed but, wherever it is, another row over nuclear waste seems certain. It will receive waste from both the new Advanced Gas-Cooled Reactors (AGRs) now coming into operation, and future Pressurised-Water Reactors (PWRs), like the proposed Sizewell B station. The plans for the dump are spelt out for the first time in evidence from the CEGB to the Sizewell inquiry, now in its fourth week. The THORP facility, which was the sub- ject of the long-running Windscale public inquiry in the mid-1970s, is expected to have a life of 10 years. It should be able to handle all spent fuel from the AGR pro- gramme up to 1997 and any PWR fuel--from Sizewell and the proposed Hinckley Point reactor--produced up to 1995. John Wright, the director of the CEGB's technology planning and research division, told the inquiry: "Whilst THORP may continue to operate beyond 10 years, it is not thought prudent to plan on this basis. It is therefore assumed that the later arisings of irradiated fuel from the currently- committed AGR stations and virtually all the arisings from any future nuclear power stations (including Sizewell B) will need to be reprocessed in plants that succeed THORP." The CEGB is already at work on a design of store to keep AGR fuel in a dry, gaseous and non-corrosive atmosphere for long periods. "Progress to date gives a high de- gree of confidence of success," says Wright. "It is unlikely that the store could be oper- ational before around 1990 but it should be available in time to provide flexibility to the timing of the reprocessing plants that will be needed in succession to THORP." The picture of the fuel cycle now emerging at the inquiry suggests that large quantities of spent fuel from nuclear power stations are going to have to be stored three times: first underwater in ponds at each power station; secondly, at the new repository, and thirdly, after reprocessing--until such time as the British government decides how to dispose of high- level nuclear waste. Last week the inquiry was assured that sufficient supplies of uranium were avail- able to meet the likely world demand in the coming 50 years. At present, the CEGB has sufficient uranium stockpiled or guaranteed under contract to fuel the nuclear programme until the end of this decade. Its controversial contract with Rio- Tinto Zinc for Namibian supplies ends next year. The only other important con- tract, with the Canadian company Rio Al- gon, is due to end early in the 1990s. Over 90 per cent of uranium used in the non- Communist world comes from the United States, Canada, Australia and Africa. The British Civil Uranium Procurement Or- ganisation is keen to get directly involved in mining and exploration. It is participating in projects in North America, Australia and Africa. [] --------------------------------------------- <2AIDS: transfusion patients may be at risk>2 AMERICAN scientists are scouring the country for the first case of the bizarre new disease "acquired immuno-deficiency syndrome" (AIDS) in patients who have undergone major surgery. The hunt for the cause of the disease, which was first diagnosed among male homosexuals, has now labelled as a prime suspect some unknown blood-borne virus. In just one year the list of people at risk from AIDS has lengthened from male homosexuals, drug-abusers and Haitians, to include the entire population. In the last year a task force under Dr Har- old Jaffe at the Center for Disease Control in Atlanta, Georgia has found seven cases of AIDS among haemophiliacs who do not fall into any of the other categories. Jaffe be- lieves that the spread of the disease may be connected with new preparations of factor VIII concentrate--the blood-clotting agent given to heamophiliacs--which are made up from blood from large numbers of donors, rather than one individual. If this is correct, any patient in hospital who is given a blood transfusion could be at risk if one of the donors of the blood carries the virus. *No cases of AIDS among British hae- mophiliacs have been reported so far--even though 50 per cent of the factor VIII used in Britain comes from the US. Omar Sattaur [] <2Green fields beyond Greenfield>2 THE GREENFIELD report, published this week, calls on the British government to save money by buying more unbranded "generic" drugs for the National Health Service. But, in Greece, the socialist government is intent on much grander measures. Measures passed in December include: a national drug company to buy from foreign companies and sell generic drugs without brand names (at low prices); a limit of three versions of any one drug to be on sale and a special tax on foreign drug firms to pay for the national company. [] <2Formula failure>2 THE WORLD Health Organisation has once again turned down an application from the Council for Infant Formula Companies (ICIFI) to affiliate to the Geneva-based organisation. The latest rebuff to the manufacturers of substitutes for breast milk came in a rare secret session of the WHO's executive board. The refusal, the third in as many years, is a symbolic trial of strength indicating the political balance of power within the WHO. Delegates from the United States had lobbied hard for the ICIFI to be affliated. [] <2Environment boost>2 THE EUROPEAN Community could spend up to $ 12 million dollars a year on the envi- ronment, if a proposal made this week by the Commission is approved by a council of minis- ters. The commission wants two environment funds, one for conservation and one to promote clean technologies--both to be effective in 1984. Each fund would receive $ 1.5 million in the first year of the scheme, increasing to $6 million by 1987. The money in the conservation fund would be available for buying or safe-guarding "sensitive areas of community interest". [] <2Safety slashed>2 THE HEALTH and Safety "Commission has slashed its programme of issuing regulations and guidance notes to ribbons. Two years ago the commission published a list of more than 100 projects. Less than 25 have been completed and the latest plan aims to finish only 26 projects during the next two years. The latest <1Plan for>1 <1work>1 reports that staffing levels now are almost as low as in 1974, when the executive was formed. But the executive is responsible for look- ing after the safety of 6 million more workers. More than 500 jobs at the HSE have gone since 1980. More will have to go in order to recruit the highly-paid staff from the nuclear industry to look after the nuclear instalations' inspectorate's work on Britain's revived nuclear power pro- gramme. [] <2Science policy goes Dutch>2 THE DUTCH government has transferred part of its science-policy department from the ministry of education and science to the ministry of economic affairs. The move, by the new coalition of Liberals and Christian Demo- crats, satisfies the Dutch confederation of indus- try, which has lobbied for more support for in- dustrial R&D and innovations. The new department will have responsibility for the Dutch Institute for Energy Research, the Dutch end of the European Space Agency, the Institute for Marine Research and for the pro- motion of microelectronics, and bio- technology. []  <2Faculties, fusion and physics win in Reagan budget>2 TRUE to form, the Reagan adminis- tration last Monday announced that national defence will get the best pickings of the federal budget for 1984. But, while social programmes continue to pay for the largesse for defence, scientific research and development has been spared. And some programmes, like science and engineering, education, are spared deep cuts. The yearly ritual of setting spending goals for the coming fiscal year, which begins on 1 October, sent analysts scurrying last weekend to find the winners and losers. Numbers tell it simply: total government spending would go up by $43 300 million, to a total of $848 500 million. That puts the Reagan adminstration in debt to the tune of $189000 million. Almost three of every four of the new dollars available next year will go for guns, if the budget is approved by Congress. The pattern is similar for the R&D portion of the government pie. Lumped together, R&D shows a 17 per cent increase. Again, two of every three dollars would go to scientists and engineers involved in defence work. Out of the total, basic (as opposed to applied) research would get $6600 million, a 10 per cent increase. With inflation expected to run at about 5 per cent, these boosts represent real gains. For some disciplines, the new budget gives cause for a sigh of relief. For others, like the space programme (not including the space shuttle) and biomedical research, the White House is content to hold steady or allow inflation to nibble away at spending power. For the feckless environmental and alternative energy programme, the march backward continues, especially for solar and conser- vation technologies. Federal budget requests are just that: requests. Congress, over the next eight months, must decide whether to honour these wish-lists. If last year's congressional deliberations are any guide, R&D should recoup some of the losses in programmes unpopular with the White House, and defence won't get everything the Pentagon would like--in effect, lopping off the extreme fluctuations while maintaining the basic thrust of the White House eco- nomic philosophy. Nonetheless, R&D that is not related to defence has declined by about 10 per cent since Reagan took office, once inflation is accounted for. As far as R&D on defence is concerned, the Pentagon is keeping specific plans under its hat, though the administration's budget makers emphasised new projects like the "Peackeeper" and Tomahawk and Trident II intercontinental ballistic missiles; more money for the "Stealth" bomber; lasers and other satellite killers; microelectronics; and, of course, the MX missile. Besides the military, the National sci- ence Foundation (NSF) earned an embar- assment of riches. It receives an unprece- dented 18 per cent increase for this year. The president's science adviser, George Keyworth, is credited with convincing Re- agan of the need for an infusion of funds into science education. In addition to spending more money on university research--especially in engineering and the physical sciences--the NSF will start new programmes to raise the calibre of science faciluties. Beginning next year, government and industry will set up five-year awards worth $100 000 a year. These will go to up to 1000 "young investigators" or promising young faculty members who might otherwise abandon academia for higher salaries in industry. For energy, the winners are physics, fusion and the breeder reactor. Though fat with money for research on nuclear weapons and nuclear waste disposal, the US Department of Energy will be leaner than ever. One bright spot will be a new materials research centre at the Lawrence Berkeley Laboratory in California. Fusion- funding remains steady, but with the money now divided mostly between the two leading machines, the tokamak and mirror-fusion. The breeder programme also lives for another year. High-energy physics is favoured, with a special nod to Stanford University. Stanford will get its linear colliding-beam accelerator on a rush basis. The hope is that the machine will beat Europe to the next prize in elementary particle physics. NASA will not get the fifth shuttle orbiter it wanted, partly because Ariane, Europe's conventional launcher, has made inroads into its market. There is no longer any need for more payload capacity. NASA's science programmes survived relatively unscathed. However, the long-planned Venus orbiting image radar, due to map the planet by the end of the decade, has been stripped of all but its mapping equipment. [] <2Christopher Joyce, Washington DC>2 <2Three Mile Island's courtroom fall--out is halted>2 A DAMAGING legal battle over the wreck of the Three Mile Island nuclear reactor has been settled out of court. The General Public Utilities (GPU), which operated the station when a faulty valve badly damaged the reactor core in 1979, had alleged that Babcock and Wil- cox, the manufacturers, failed to issue warnings about known deficiencies in its pressurised water reactors. The GPU claimed $4000 million in damages. Babcock countered that the plant's oper- ators had all the information that they needed to cope with the crisis. But they failed to stop the accident because staff were poorly trained. Last week, the case came to a sudden end. The two sides announced that they had settled out of court. Babcock will give GPU up to $37 million over the next 10 years--but only in the form of rebates on orders that GPU places with the firm. The money is a small fraction of the estimated $1100 million cost of cleaning up the stricken reactor. There is widespread suspicion that the two firms, along with the rest of the nuclear industry, were appalled by the revelations about operating methods at the power sta- tion that had already been given in testi- mony. They feared that, unless they settled their differences, further disclosures could cause permanent damage to the already- scarred image of the nuclear industry. The court heard the shift supervisor at Three Mile Island change his testimony on the crucial relief-valve temperatures that were reported to him during the incident. And GPU's lawyers made great play of a document, written by Babcock staff before the TMI accident, that suggested new pro- cedures to recognise the signs of impending accidents before they happen. GPU hasn't given up the courtroom en- tirely. A spokesman for the company said that last week's settlement will not affect its $4000 million suit against the Nuclear Regulatory Commission. GPU alleges that the commission failed to warn it about the safety hazards of the Three Mile Island reactor. Peter Gwyane [] <2Reagan accused of wrecking acid rain talks>2 SCIENTISTS from Canada and the United States have given up attempts to agree about what effect acid rain is hav- ing on the environment of North America. After more than two years of discussions they have decided to publish two separate statements, one from each country, in the next few weeks. The Canadian scientists on the working party blame political inter- ference from Washington for their failure. The two countries signed a memo- randum of intent in August 1980, when President Carter was still in charge in Washington. It committed them "to de- velop a bilateral agreement to combat transboundary air pollution". Four work- ing groups were given the job of providing negotiators with scientific and technical in- formation. They should have published their reports a year ago. In fact, a draft of the report of group I--on the effects of acid rain on the environment--has been ready for more than a year. But the two countries cannot agree on the crucial question of whether, as the Canadians maintain, the evidence shows an immediate need to fix a limit on emissions of sulphur dioxide. A target of 20 kilograms per hectare a year has been pro- posed by the Canadians and backed by a number of scientists from the USA. But the official position of the US is that there is not enough information yet to justify expensive remedial action. Washington has blocked publication until the Canadians threatened to publish unilaterally. Then the Americans agreed to release the main report--with two sets of conclusions. Washington's Secretary of State, George Schultz, and the Canadian external affairs minister, Allan MacEachen, now plan to meet to discuss the row in the spring. Half of the sulphur deposited in Canada comes from the United States. Last year, during the negotiations, Canada offered to spend $ 10000 million reducing acid emi- sions from power stations and copper smelters--provided Reagan agreed to match it. He did not. The Canadians say that sulphur, falling as acid rain, is killing fish in the lakes of southern Ontario and Nova Scotia and damaging forests. Behind the breakdown in discussions are charges from the Canadians that the Reagan administration has systematically disrupted the work of the scientists. One Canadian official told <1New Scientist>1 that scientists from the US have been replaced by "people with less relevant experience, and some who have been acting as political commissars". Since Reagan took office the two most important working groups (numbers I and IIIA) have each had three successive US co-chairman. "If you want to slow down the game," said another Ottaw'a official, "one good tactic is to keep changing the players". When work group I met last June to ratify the final draft of their report, the US co-chairman, Claire Harris, did not appear. In his place came five new Americans. Garth Bangay, the Canadian team leader, accused them of "blatant interference". The draft was not ratified. Reagan is also being accused of ordering scientists to ignore the terms of reference of the memorandum. In July 1981 the co- ordinating committee, which oversees the work groups, told group IIIA, whose job it is to recommend strategies for achieving proposed emission reductions, to drop this work. It said: "The committee has concluded that the control strategy development activities of IIIIA should most appropriately be carried out separately in each country." Canadians say that the letter, whose existence has not previously been revealed, was written at the insistence of the Americans. The US government also vetoed a plan to have the reports of the working groups reviewed jointly by the US National Academy of Sciences (NAS) and Canada's Royal Academy of Sciences. The veto followed a report by the NAS, which concluded that action to reduce emissions should be taken. Instead there will be independent reviews. Canada's will be con- ducted by the Royal Society and the US's by' a committee headed by Willian Nierenberg, who most recently chaired President Reagan's panel on the basing of MX missiles. [] <2Shuffle hitch delays Spacelab launch>2 TEETHING troubles with America's second space shuttle, Challenger, could disrupt plans for the first flight of Europe's Spacelab this autumn. Spacelab is an aluminium cylinder, packed with sci- entific experiments, that the European Space Agency has built for shuttle flights. The maiden voyage may have to be post- poned for five months as a result of a fault in one of Challenger's fuel tanks. NASA engineers said last week that the fault, which has lead to leaks of dangerous liquid-hydrogen, will put back Challenger's first trip into the heavens by several weeks, probably to March. The flight should be the sixth test of the shuttle; the first five trips were all by the shuttle vehicle, Columbia. Before Spacelab enters orbit, the Euro- pean Space Agency must launch a couple of other bits of hardware. Called the Track- ing and Data Relay Satellites, these will stay in geostationary orbit 36000 km above the equator, relaying data between Spacelab and the Earth. The scientific value of the Spacelab mission would be greatly reduced if the two craft are not in place. Only a few launch dates are possible for Spacelab. This is because astronomical ob- servations using the hardware can take place only at certain times of the year. In practice, the next launch "window", if Spacelab fails to make the schedule for either September or October, is February 1984. But the engineers planning the #500 million Spacelab programme have grown accustomed to delays. * Ariane misses the bus, p 308. [] <2Lead report brings new alarm over petrol>2 THE BRITISH government's claim that it is not necessary to remove lead from petrol received another body-blow last week. A report by a Ministry of Agriculture, Fisheries and Food provided the first offi- cial acknowledgment that lead fall-out from cars contributed significantly to the lead content of food. The government's case for retaining lead in petrol has been based heavily on the 1981 Lawther report. Lawther concluded that in- halation was the only significant source of human exposure to lead from vehicles. It contributed no more than 20 per cent of the lead in the blood of adults and 10 per cent in children. Now, however, a working party on heavy metals in food has concluded that 16 per cent of lead intake in the average diet comes from the contamination of food crops by lead--almost almost all of which comes from petrol fumes. That brings the officially acknowledged contribution of petrol-lead to blood-lead up to 30 per cent in adults and nearly 25 per cent in children and boosts the case against lead in petrol. [] <2New plastic bullet squirts noxious chemicals>2 THE CAMPAIGN against the use of plastic bullets by the police, which was launched this week by the British Society for Social Responsibility in Science and the National Council for Civil Liberties, comes just in time to fight a new "technological fix" on offer from the Ministry of Defence --a rapid-fire gun designed for riot control. The new weapon, the Arwen-37, projects a CS-type gas from the front of the club shaped plastic bullet. It was developed at the Royal Small Arms Factory in Enfield. The MoD applied for three patents last year. It hopes for a significant export trade in this latest answer to civil disorder. The campaign is supported by Labour and Liberal MPs as well as distinguished scientists and jurists. It is urging police authorities to instruct their chief constables not to use or stockpile plastic bullets-solid PVC cylinders 10 cm, long, 38 mm in diameter and weighing 135 grams. Plastic bullets were invented by Porton Down scientists for use in Northern Ire- land. They were first authorised for use in Britain during the Toxteth riots of 1981. Now some 10 000 rounds of plastic bullets are stockpiled by police forces throughout Britain.  Eleven people, including children, have been killed by plastic bullets since 1972, when these "plastic baton rounds" replaced rubber bullets in Ulster demonstrations. Officially, the weapon deters rioters by producing a harmless but "stunning pain. specialist on pain at University College London, "you cannot produce a stunning pain without injury. Being hit by a plastic bullet is like being hit by an ice hockey puck at 250 km per hour--without the benefit of the goalkeeper's protective clothing". Round for round plastic bullets have killed over four times as many people as their rubber predecessors. Surgeons at Belfast's Royal Victoria Hos- pital have had ample opportunity to study the effect of these projectiles. Dr Laurence Rocke is now sending his findings to <1The>1 <1Lancet.>1 The injuries caused by plastic bullets are similar to those described in an earlier study of rubber bullets, Dr Henry Rutherford of the Royal Victoria told <1New>1 <1Scientist.>1 "When a missile hits the head, neck, and to some extent the chest, the results are very serious--or even fatal." Already at least 10 of the 43 police authorities in England and Wales either do not have any plastic bullets or do not favour their use, according to Patricia Hewin of the NCCL. [] <2Wolff plans a tool kit for>2 <2the elderly>2 HEINZ WOLFF is to quit his post as head of the Medical Research Coun- cil's bioengineering division. He will join the new Institute of Bioengineering at Brunel University in the spring. The new institute, which got the go- ahead from the university's council last month, will develop technology to meet the needs of the elderly and the disabled. It will also design instrumentation for in- vestigating the problems of man in haz- ardous environments and develop appara- tus for use in biological research in space. Wolff is seen as a big asset to the institute in winning outside finance. "We have every confidence that Heinz Wolff will continue to get support from outside agencies," said a spokesman. Wolff announced his move at the national conference of Age Concern on Monday. He said he wanted to devote his time to developing "tool kits for the elderly". All other age groups had their "tools" for life--such as baby walkers, roller skates and computers. The old were stig- matised by having "aids". He added: "Aids for the disabled are the first glimmering of a further development of our culture, most of which has been con- cerned with the development of tools. We have not yet got a tool kit for the elderly--like computerised personal alarms--because the elderly <1en masse>1 are a modern phenomenon." Wolff will not sever his links with the MRC until spring 1984. He will work at both centres until that time. [] <2Troubled waters for bishop, brewery and Tory>2 THE PLACID waters of the Alresford reservoir near Winchester, Hampshire, are being stirred by a bizarre dispute in- volving a prospective Conservative MP, Watney's brewery, the Bishop of Winch- ester, and district county and water author- ities. At issue is who owns the reservoir--and who is responsible for en- suring that the leaky embankment that holds the water in does not give way and engulf a street of houses. To complete the tale, one of the houses is owned by a Mrs Flood. The dispute should have been settled 53 years ago when the 1930 Reservoirs Act ruled that the owners of all reservoirs con- taining more than 23 million litres must have them inspected and repaired regularly. But last month the Department of the Envi- ronment revealed that, out of more than 1500 large dams it knew about 191 have no known owner--and many more have no cer- tificate of safety. Most of the Al- resford reservoir-- which began life in the 12th century as a fisheries pond for the Bishop du Lucy--is now owned by the Al- resford House Estate Trust, one of whose trustees is the pros- pective Conservative candidate for Stoke- on-Trent South, Peter Maxwell. Maxwell told New <1Scientist>1 that the sluices do need reme- dial work to make them safe. But the family estate was "in no way in a position to spend large sums of money on repairs." And, anyway, the estate disputes that it is responsible for the leaking embankment. It is only responsible for the reservoir itself and for the sluice gates, says Maxwell. There are plenty of reluctant candidates for ownership, according to Winchester district council, which is trying to get to the bottom of the matter. Watney owns a pub on the embankment; the Bishop of Winchester once owned the land but gave up all title in 1884; Hampshire county council recently widened the road that runs along the top of the bank, but it refuses to get involved. If the dam, which has leaked at its toe for as long as any one ean re- member, should collapse, it would sweep away the busy tourist road the B3046, seven houses and their inhabitants--and quite probably, the Parliamentary career of Peter Maxwell. <1Anne Charnok>1 [] <2In search of the perfect cocoa bean>2 <2The world's plantations of cocoa are short on genetic variability. Wild plants, in the Amazon, may contain>2 <2the required genes. The first problem, is to find them>2 <2John Allen>2 IN <1New Scientist>1 in October 1979 I saw a rather unusual job advertisement: "Plant collecting in the Amazon". lt was not joking. Three months later I found myself settling down to life on a research station in the Amazon rainforest in eastern Ecuador. My job, financed by the London Cocoa Trade, was to collect wild cocoa. Cocoa cultivation spread so quickly around the world that all the crops derived from only a few wild ancestors, so that modern cultivated varieties suffer from a lack of genetic variation. This means that plant breeders who try to create higher-yielding or disease-resistant varieties by selection or hybridisation from existing varieties can make only limited progress; the genes they need are simply not found in the cultivated populations. But such genes may be found among wild cocoa trees; there were spectacular increases in yield and a partial increase in resistance to disease when the first collections of wild cocoa from the Upper Amazon, made by J. F. Pound in 1937-38, were supplied to breeders in the 1940s. Forty years ago, the forests along the eastern fringe of the Andes were as inaccessible as anywhere in the world; but it is there that is found wild cocoa with the greatest genetic diversity. In the past 10 years, with the discovery and exploitation of important oilfields from Venezuela south to Bolivia, roads and airstrips have been built, colonists have poured in, towns have been founded and the rainforest is disappearing. It is now much easier to travel in these areas, but collecting wild cocoa and other species of the rainforest has suddenly become very urgent. The London Cocoa Trade Amazon Project, as my collecting programme had been christened, was to be the first stage in a rescue operation. With the support of the government agriculture research institute (INIAP) in Ecuador, I would have systematically to travel through the Amazon region of Ecuador, locating the wild cocoa and bringing back planting material to my base at the Napo Research Station. The area around the Napo station is a microcosm of the region. Fifty kilometres to the north, the American oil com- pany Texaco drilled its first productive well in 1967 in a clearing in the forest, bringing in its drilling rig by air as there were no roads. That well, still producing, is now almost sur- rounded by a town of 25 000 people, called Lago Agrio. From Lago Agrio a gravel road leads through the jungle and up into the Andes, reaching Quito, the capital of Ecuador, over a 4000 m pass. Another road runs south, through the oilfields, and is constantly being extended into virgin forest. Alongside these roads runs the 700 km trans-Andean pipeline, and there are side-roads and branch pipelines leading to about 200 individual oil wells. Ever since the roads were first planned, the colonists have been arriving, escaping frorn poor-quality land, drought, landowners and overpopulation in other parts of Ecuador. Now they are settled along the roads; each family is allowed to claim title to a 50 ha block of land, with 250 m of road frontage, and 2 km deep. Behind the first line of colonists is a second, and a third, and so on, some families being 10 km or more from the road along a muddy footpath. Throughout this settled area, the forest is being cut down. The farmers plant one or two crops of maize or manioc, and then use the land mainly as pasture for cattle or for small planta- tions of coffee. Around Napo, after 15 years of colonisation, there are still appreciable areas of untouched forest within 1.2 km of the road; elsewhere in Ecuador, after 30 or 40 years of colonisation, one can walk for a day away from a road with- out reaching the forest. Arriving at Napo, I discussed plans for collecting with the INIAP technician, Jose/ Baquero, who was to be my assistant on the project. We supervised the clearing of land for a nursery and for the permanent planting of the wild cocoa after it had been collected. Some earlier teams collecting wild cocoa had lost 50 per cent or more of their material by attempting to send it directly to distant breeding centres; our intention was to bring the collections back to a local base for propagation and planting. The plants at Napo would then serve as a "gene bank" from which to send material to breeders anywhere in the world. The gene bank would also help Ecuador's own cocoa-breeding programme, run by IMAP in the traditional cocoa-growing area in the Pacific coast region. By June 1980 we were ready for our first serious collecting trip. We chartered a STOL (short take-off and landing) air- craft from the Summer Institute of Linguistics, a missionary organisation, and flew to Loreto, which from the map appeared to be a promising area for collecting as it had no roads and therefore no colonists. I later discovered that the area was one of those settled by the original Spanish <1conquis->1 <1tadores>1 in the 1560s; by 1980, Loreto itself, still largely cut off from the outside world, consisted only of a church, a school and five houses, although there were many more Indian families in houses scattered through the surrounding forest. Our plane landed and was immediately surrounded by chil- dren from the school, although the arrival of aircraft is no great novelty in the many villages in the region that have an airstrip but no access by road. We were made welcome by the teachers, provided with a floor to sleep on, and within an hour had set off into the forest to look for wild cocoa. Here we were not disappointed. As it turned out, we only once failed to find wild cocoa in all the areas we visited throughout the region. At Loreto, we spent three days exploring the network of muddy paths through the forest around the village, crossing small streams on logs and one larger river on a suspension bridge which consisted of four rusting steel cables and a few loose planks. In the forest here, as elsewhere, the wild cocoa trees reach their full natural height of 20 m or so (under plantation conditions cocoa trees rarely exceed 10 m) and develop as clusters of a dozen or more leaning trunks. As the oldest trunks fall over, they are replaced by new shoots which appear continually around the base of the tree. The trunks that fall over sometimes take root several metres away from the base of the tree, at which point a new tree will grow up. This habit of growth means that a wild cocoa tree may be effectively immortal, which is just as well because, as we soon discovered, these trees produce very few pods. Collecting wild cocoa is relatively easy if the trees have pods. One collects them by climbing the tree or by poking them with a long stick. In the wild, even ripe pods do not fall off the trees; they are opened <1in situ>1 by squirrels or monkeys which suck the sweet pulp off the seeds. The seeds fall to the ground where they germinate immediately. Although most trees produce few seeds in any year, the energy stored in each seed is sufficient for a seedling to grow for several weeks with little or no photosynthesis. This is an important adaptive feature for a species that must reproduce under the dense canopy of primary forest. Long individual lifespan, a low rate of seed production and large seeds constitute, indeed, the classic "strategy" of tree species in stable forest environ- ments. An unopened pod taken from the tree will keep for at least three weeks, and when opened back at the nursery it is usual to obtain 100 per cent germination of the seed. Even when pods have to be opened in the field, to save weight on the return journey, the seeds can be kept in good condition for two weeks by packing them in damp charcoal. Unfortunately, life is rarely so easy for the cocoa collector. Deep in the shade of the forest, few flowers are formed and pods are even rarer, for another peculiarity of cocoa is that only a tiny proportion of flowers--less than one per cent--are successfully pollinated. It is then necessary to collect budwood: short lengths of young branches with dormant growth buds. With the ends waxed to reduce water loss, and packed in damp newspaper, budwood can just about survive for 10 days, until back at the nursery the buds skill and experience, this operation can be exasperatingly with skill and experience, this operation can be exasperatingly unsuccessful. We returned from Loreto with pods from two wild cocoa trees and budwood from another 15. Our collecting had be- gun successfully although I had failed to realise how cold it could be at night in the forest. We had forgotten to pack our blankets, and slept badly on the hard bamboo floor. By the end of 1980 we had made 160 collections and, despite problems with the budding technique, nearly 130 of these were safely growing in the nursery. We had also gained confidence in our col- lecting methods as we trav- elled more widely. Some interesting areas, particularly in the extreme south of the region, could be reached by road after four days' driving along the Andes. Here, in the valleys of the Rivers Zamora and Upano, several generations of co- lonists had cleared much of the forest, replacing it with pasture grazed by cattle. Fortunately for us, they had developed the custom of leaving a few of the wild cocoa trees when they felled the forest. These trees, in full sunlight, were growing more vigorously than the forest trees and produced enough pods to make our life easier. However, they were also more badly infected with witches' broom disease. This disease has devas- tated cocoa plantations in several countries; it is caused by a fungus which produces broom-like clusters of deformed shoots on the branches, and also infects the pods, making them worthless to the farmer. The hope of finding wild trees with natural resistance was a major reason for collecting wild cocoa in the Upper Amazon. Previous expeditions had often collected from disease-free trees in the forest, but only a few of these trees had shown useful resistance in later trials. Now it seemed to us that freedom from disease was more likely related to the weak growth of the trees in the forest. This confirmed an earlier decision: as a general principle, we would not try to collect only those trees that seemed at first sight to be superior. After all, a plant that was doing badly in the Amazon may well do well else- where, or at least contain genes that would be useful in other environments. Our collections would be a random sample from the wild cocoa population, to be handed over to cocoa breeders who could screen them for genes that would be useful under their own conditions: a genotype that was susceptible to witches' broom disease might still be useful for other reasons to farmers in West Africa, where this disease does not occur. We continued collecting through 1981, visiting ever more remote parts of the country, and using a variety of forms of transport. I learnt how to recognise a well-built, stable dugout canoe--it's no fun capsizing in a fast current with the river bank several hundred metres away. I also learnt the difference between a Helio Courier and a Pilatus Porter, two types of STOL aircraft often used in Ecuador; the former small and cheap to charter, the latter costing #150 an hour but able to carry a collecting team of three people, with our usual equip- ment and the 500 litres of petrol needed for a long river trip. Away from the roads, most areas we visited were populated by Indians: Cofan, Secoya and Siona in the north, Quichua and Huaorani (Auca) in the central part of the region, and the Shuar in the south. The existence of large areas of apparently uninhabited forest, as seen from the air, is deceptive; the largest areas of fertile soils are found along the main rivers and these are quite densely populated, while the forest beyond serves as an indespensable hunting-ground for people whose diet is based on protein from the wild rather than domesticated animals. Wherever land has been colonised the Indians have lost much of their land. Only recently, Indian organisations such as the Shuar Federation have persuaded the government to grant legal titles to communal Indian land holdings, and in some cases this has been possible only after foreign volunteers have carried out the necessary land surveys. Although both the Indians and colonists are involved in actual and potential conflicts, the people we met almost always helped in our work. Travelling along rivers, we were offered shelter and space to sleep; houses in the jungle have large floors to accommodate frequent visitors. Discussions about wild cocoa would be accompanied by the drinking of bowls of <1chicha,>1 the daily staple diet of the Indians, made by the women from manioc: ground, masticated, and fermented. After such discussion one of the men would usually offer to show us a wild cocoa tree in the forest beyond his planted clearings. Only one river, the Curaray, proved uninhabited for a considerable distance. Here, after flying into one village, we travelled downstream slowly for four days, sleeping on sand- banks as the river was low. Every morning we woke to find ourselves surrounded by fresh tracks made by capybaras (the world's largest species of rodent, looking something like a giant guinea pig); on our last evening, the boatman killed an alligator as it crawled past our camp-fire to go hunting in the reeds beyond. Every few minutes down the river we would see a wild cocoa tree on the bank, and exploring in the forest behind we usually found many more trees. Only a few of these had pods, but here and elsewhere we found enough pods to make an important observation: all the wild cocoa throughout the Amazon region of Ecuador shares a common set of genetically determined characteristics including white seeds, very rough-surfaced yellow pods, and the absence of red pigmentation in the leaves. As these features are not found together in any group of cocoa varieties already in cultivation, this is definite evidence that we have added some new genes to the "gene pool" of cultivated cocoa. Back at Napo, the young cocoa trees in the nursery were growing well, and in February 1981 we planted out the first trees in our "gene bank". We planned to include 10 plants from each collection in the bank, enough to offset the risk of trees dying through disease or neglect, while keeping the over- all area within manageable limits. We hoped that the gene bank might ultimately contain 500 collections, and we knew that maintenance would become a problem sooner or later. Evaluation of potential new varieties held in such gene banks is a long-term affair; for example, it may take 10 to 15 years to prove disease resistance. Agricultural research organisations in most countries are affected periodically by shortage of money or political instability, and it is diffcult to assure the continuity for breeding tree crops such as cocoa. By the end of 1981 we had 310 collections and reckoned to have covered about three-quarters of the region. It was time to turn our attention to another aspect of the project: sending our wild cocoa to quarantine, before sending it on to breeders in Brazil, West Africa, Malaysia or elsewhere. Quarantine is important, because each cocoa-growing area suffers from a different set of diseases. The most catastrophic disease, witches' broom, has never spread beyond South and Central America and the Caribbean; even in Brazil, it occurs only in the Amazon basin and not in the main cocoa-growing region of Bahia, 2000 km to the south-east. On the other hand, swollen-shoot disease, caused by a virus, is found only in West Africa. Cocoa can be held in quar- antine at the Royal Botanic Gardens, Kew, and at Mi- ami. At Kew, a large green- house, with temperature and humidity controlled at tropi- cal rainforest levels through- out the year, contains a col- lection of several hundred clones of cocoa (clones being groups of genetically identi- cal individuals that have been derived fom a single parent by asexual re- production). Plant breeders anywhere in the world can write in to ask for budwood from these clones, some of which are wild in origin while others have been selected from plantations in various coun- tries. Each clone must have been grown for at least 18 months at Kew before being distributed; during this period, the plants are regularly inspected for disease and insects. As far as is known, no disease ever has been transmitted with cocoa ma- terial distributed from Kew, but the danger is real, and with- out such quarantine facilities the spread of such diseases as witches' broom would be almost impossible to prevent. The special characteristics of most of the clones held at Kew are listed in documents such as the <1International Cacao Cultivar>1 <1Catalogue,>1 so that the breeder can request clones with features relevant to local needs, such as ease of propagation by cuttings, or ability to grow well without shade. What of the future? We have nearly finished collecting in Ecuador. There remain some inaccessible areas close to the frontier with Peru; again, we are in luck, because the state oil company CEPE is drilling exploratory wells there, and has offered to fly us in by helicopter. At Napo, the "gene bank" is filling up, and the first trees, planted 20 months ago, are 2 or 3 metres high and growing fast. We have begun to measure these trees, noting characteristics that give us clues to their genetic relationships: these trees, growing under plantation conditions, will eventually tell us whether we really have col- lected new genes useful to farmers who grow cocoa. However, we are not the only team collecting wild cocoa. The Brazilian cocoa research organisation, CEPLAC, has or- ganised a series of expeditions in the Amazon region of Brazil, a vast area that will take many years to cover completely. Some collecting has been done in Colombia and Peru, but not enough; in Central America, some primitive cultivated vari- eties in danger of extinction are now preserved in the germ- plasm collection at Turrialba in Costa Rica, but there, as elsewhere, the present-day status of the wild cocoa popu- lations remains mysterious. Only one thing is certain: the search will continue for many years to come. [] <2Quiet craft hovers ahead of competition>2 <2The choice of marine rather than aerospace technology makes the British Hovercraft Corporation's>2 <2new ferry the quietest and cheapest yet. Overseas manufacturers are already imitating the design>2 <2Mark Hewish>2 A NEW type of hovercraft starts passenger services across the Solent this month. The British Hover- craft Corporation AP1-88 looks much like the SR.N6s that already ply the route between Southsea and Ryde on the Isle of Wight. Under the skin, though, the craft are sufficiently different to gen- erate cautious optimism that the hovercraft is at last com- ing of age. Compared with its predecessors, the AP1-88 is cheap to buy and operate, and it is much quieter. The hovercraft has always suffered from the fact that it is neither fish nor fowl. The first one took to the water in 1959. Although most customers want something like a conven- tional ferry, but faster, manufacturers have generally used materials and construction techniques from the aircraft industry. The result is an expensive machine: fine for the military, but always on the borderline of profitability. When fuel prices soared in the 1970s, Seaspeed and Hover- lloyd, running big hovercraft across the English Channel, started losing money and later merged to form Hoverspeed. This seemed like the hovercraft's end, but it spawned the technology that made the AP1-88 possible. Seaspeed had asked the British Hovercraft Cor- poration (BHC) to make the cross-Channel SR.N4 more profitable. BHC cut the machine in half and put in a central section to carry more cars and passengers. The stretched craft, the "Super 4", needed a new design of skirt, the flexible rubber structure that holds the supportive air cushion under the hovercraft. BHC engineers came up with a floppier, tapered skirt that allowed them to reduce the pressure of the air cush- ion. Less power was needed to keep the skirt inflated, so the engines burned less fuel. Hoverspeed's two Super 4s can carry 70 per cent more payload (passengers and cars) than the unstretched SR.N4s, but cost only 15 per cent more to run. BHC has since adopted the same skirt design for the latest version of the smaller SR.N6, raising its payload from 10 to more than 17 tonnes. Hovertravel, which runs the Southsea-Ryde service, also hit trouble. Its 55-seat SR.N6s, built in the mid-1960s, were too noisy for modern ears. Southsea and Medina councils, under pressure from residents and bodies such as the Solent Protection Society, delivered an ultimatum: make less noise, or stop operating. Hovertravel wanted a quiet, cheap replace- ment for its SR.N6s. It joined forces with BHC on the AP1-88, with the British Technology Group chipping in #237 500 towards the development costs. The target was a craft that cost half as much as the SR.N6 to buy. The skirt developed for the Super 4 was more efficient than its predecessors: less of it touched the sea, so less power was wasted in overcoming water resistance. This al- lowed the AP1-88's designers to use a heavier structure. Where previous designs had riveted aluminium-alloy plates for the structure and gas turbine engines, the AP1-88 employs marine construction methods and diesel power. As BHC says, it has moved from building low-flying aircraft to making high-flying boats. Continuous welding of marine - type aluminium alloy is faster and cheaper than riveting. The API-88's air-cooled truck diesels that provide both lift and pro- pulsion are heavier than the converted aero engine that powers the SR.N6, but they burn less fuel and cost only one-fifth as much. Another advantage is that, unlike gas turbines, diesels need little maintenance: a partial ser- vice after 2000 hours run- ning time in the API-88, followed by a complete over- haul after 8000 hours. Oper- ators can obtain spare parts locally, and mechanics need no special training. The propellers are res- ponsible for most of a hovercraft's noise, especially the tearing sound made as the blade tips approach the speed of sound. The API-88 uses two propellers which have a tip speed 40 per cent less than that of the single unit on early SR.N6s. Cylindrical ducts shield the propellers and increase thrust at low forward speeds, by preventing air from spilling sideways around the blade tips. For the first time in a BHC hovercraft, the API-88 has separate engines to provide lift and generate forward speed. Earlier types have run at high power, even when manoeuvr- ing at slow speed, to keep the skirt inflated. This produces a lot of propeller noise at the hovercraft terminals, and annoys nearby residents. The AP1-88 is only as noisy as a major road ata distance of 100 m to 200 m, and at I km is no noisier than a quiet residential area. The craft's rear structure minimises turbulence in the air flowing into its propellers to reduce internal noise. Hovertravel plans to put the first API-88 into service in early February, with a second machine following before Easter. These two prototypes carry 80 passengers each. Fairey Allday Marine at Gosport, which specialises in boats of welded aluminium, constructed both hulls. They were towed to Hovertravel's works on the Isle of Wight for finishing. BHC decided late last year to build five full-scale AP1-88s, each carrying 101 passengers, at its Cowes factory even though, so far, it has signed no further orders. The company has bought the necessary continuous-welding machinery and is training operators. BHC has spent about # 1 million directly on developing the AP 1-88, in addition to the BTG grant (which it will repay from a levy on sales). Much of the #1 million spent annually on hovercraft research and develop- ment over recent years is also directly applicable to the AP1-88. The AP 1-88's four identical turbocharged, 12-cylinder Deutz diesel engines, each with a capacity of 19 litres and producing 315 kW of continuous power. Two drive the fans, on each side of the hovercraft; three to pod, three to star- board. The forward pair of fans supply air to two swivelling nozzles that point rearwards during cruising to produce extra thrust. They are swivelled by a handwheel in the control cabin to steer the craft at low speeds. The remaining four fans inflate the skirt to provide the cushion that keeps the Al-88 above the sea. The propulsion engines drive the propellers via toothed belts, removing the need for the complicated transmission used with gas turbines. The wooden propellers have fixed blades--another simplification compared with the variable- pitch propellers that BHC used in the past to alter the thrust. Rudders behind the propellers work in concert with the swivelling nozzles to steer the hovercraft. The AP1-88 is 23-55 m long and weighs 36-3 tonnes when fully loaded. It can carry its 101 passengers at more than 80 km/h across waves 1.5 m high. The craft's endurance will be 2.2 hours which can be increased to 5.25 hours by decreasing the number of passengers by 10 (these figures assume that each passenger carries 90 kg of baggage). A half-cabin model has also been planned. This would carry 40 pas- sengers plus a cargo. Access to the deck is designed to allow light vehicles to be driven aboard. This version would be suited to rescue, survey or inshore oil field support work, says the BHC. A version, with a cargo- carrying deck in place of the passenger cabin, for military and offshore-industry appli- cations can ferry loads weigh- ing more than 8 tonnes. The suggested design has a flat deck 15x4.8 m with access via a 2.7 m wide bow ramp. The trials have gone well, according to BHC, with only minor modifications neces- sary for the production ver- sion. The company will shift the engines and fuel tanks forward to increase the dis- tance over which the centre of gravity can move without limiting the load. Firewalls have proved necessary to reduce heating of bearings caused by the engines, but the skirt design has proved satisfactory without modi- fications. The British Hovercraft Corporation has fixed a price of between #1 . 1 million and #1-2 million for the AP1-88, depending on the layout. The company says that it has received inquiries from about 470 companies, of which perhaps a quarter are potential customers. BHC is having detailed discussions with four of these and hopes to sell 90-100 AP1-88s over the next decade. The simple con- struction method allows the company to build an AP1-88 in nine to ten months. The corporation has prepared a detailed indication of run- ning costs for the new hovercraft. It suggests that the machine will cost about #120 for every hour of service. This figure assumes two craft in use, each running for 2000-3000 hours a year over an average 19 km route at 55 km/h. Fuel con- sumption is taken to be 336 litres/h. Other hovercraft designers scoffed at the idea of the AP1-88 when is was first announced, saying that BHC had mis- calculated its figures. Rivals in Britain, Japan and Finland are now coming out with their own similar designs. For the future, the company has its eyes on scaled-up versions to carry 200 to 250 passengers and is studying other ways to apply aspects of AP1-88 technology. [] <2Mules must come to science>2 <2Hybrids between jack donkeys and mares, or stallions and she-asses, are outstanding subjects for>2 <2research in reproductive biology--both animal and human>2 <2Sir Cyril Clarke>2 "SURE of foot, hard of hide, strong in constitution, frugal in diet, a first-rate weight carrier, indifferent to heat and cold, he combines the best of the most homely characteristics of both the noble houses from which he is descended." So wrote Rudyard Kipling's father about the mule in the 1890s. Today, quite apart from its scientific interest, the mule, offspring of a donkey and a mare, has enormous economic potential: as a work animal, the mule's life is almost twice that of the horse; it pulls more in propor- tion to its weight; it needs shoeing less often; and it can be worked in large teams without difficulty. In 323 BC Alexander the Great's funeral carriage was drawn by 64 mules, and much earlier, around 1000 BC, Homer had extolled mulish virtues. The mule is very much a product of artificial selection, for although wild horses and asses have roamed together in parts of South America there appear to be no records of naturally occurring hybrids. Both the mule and its much less common reciprocal, the hinny (by a stallion out of a she-ass), are the result of man's observations and interference. But how did they come about? When horses and donkeys are pastured together there is no doubt that each species mates preferentially with its own kind. Occasionally, however, there are "kinkies" who prefer a change; mules and hinnies are the inevitable result. Their Kipling characteristics would surely have immediately attrac- ted man's attention, and he would soon have thought up other ways of increasing the frequency of such useful animals. One technique is to excite a jackass with a jenny donkey and then <1au moment critique,>1 substitute a mare. Later came arti- ficial insemination, which is now the standard practice on the large mule farms of China. The best type of donkey to use as father is the subject of some debate. Many say that the donkeys from Poitou in France are particularly suitable for siring mules, perhaps because they are particularly large, but it now seems doubtful that size is of any special virtue in obtaining the hybrid. There are, however, other advantages in the way the Poitou donkeys are managed. They are, for example, given frequent oppor- tunities to mate but only with mares. The size of the mare too seems to be of little importance, and mules are much more alike than their parents might seem to suggest. Arend Lourens Hagedoorn, a Dutch geneticist at the University of California, wrote in his book <1Animal Breeding>1 (1954): "It is astonishing to see the enormous variety between the mares and the uniformity of the mule foals. The mares differ as much as horses can differ. The mules look as if they were turned out by machine." The union of two separate species may shed light on the processes of pregnancy and gestation. For example, do mules suffer a greater risk of being miscarried? The gestation period of a horse is about 11 months, that of a donkey 12 to 13 months, and that of the hybrid somewhere between 11 and 13 months. But how often is the mule's gestation cut short by spontaneous abortion? In 1884 the editors of the <1Encyclope->1 <1dia Britannica>1 were certain that miscarriages occurred more readily with mule fetuses, and advised that "more care is necessary than in breeding horses or asses". A hundred years on we are much less certain; it all depends. For example, racehorses abort all too frequently, which is particularly gall- ing after a large stud fee, but I know of no accurate informa- tion about the comparative frequency of abortion of the four types of conceptus (horse, donkey, mule and hinny). The matter is of more than passing scientific interest. No one knows exactly why a fetus is not automatically rejected by the mother's immune system. It carries paternal antigens and is there- fore a foreign body that ought to be attacked, and to obviate this there are probably blocking factors that prevent the pater- nal antigens from eliciting any reaction. In a between-species cross, in which there is even greater dissimilarity between the antigens, one would expect the rejection to be even more axiomatic, but the immunological evidence is difficult to interpret. Mares carrying their first fetus produce much <1higher>1 levels of antibodies if the fetus is a horse than if it is a mule, the exact opposite of what one would expect. However, in the specialised cells that support and nourish the fetus the immune reaction is greater against a mule fetus than against a horse fetus. This is as expected, but it does not seem to matter, as Dr W. R. Allen of the <1ARC>1 Unit of Reproductive Physiology and Biochemistry at Cambridge has shown. Perhaps the blocking antibodies are all-important and can cope with the increased antigenic differences in hybrids, but this is only a speculation, and more work needs to be done. Miscarriages--or the lack of them--in these animals may be highly relevant to our own species, and the story starts, surprisingly, with renal transplantation. Ten years ago I used to plead with kidney doctors to give my patients transplants. The standard answer, given with that gleam of superiority that the young delight in, was, "No, Dr Clarke, they are not suitable because you have given them a blood transfusion." At the time the experts believed that a previous transfusion sensitised the patient and made it more likely that a trans- plant would be rejected. Now the specialists have had to stand on their heads, because previous transfusions are known to be very helpful in making a kidney "take"; the modern kidney doctor will not usually accept for transplant a patient who has <1not>1 had a transfusion. "Protective factors" are said to be the explanation. but what these are is not yet clear. The parallel is with women who habitually miscarry for no known reason. C. Taylor and W. Page faulk found that such women often have white cell antigens (HLA) that are unusually similar to those of their husbands. Again, this is a most unexpected and unexplained finding; similar antigens should lessen the chance of rejection, not increase it. If, however, these unfortunate patients are given transfusions of white cells from several incompatible donors during pregnancy, they carry normal babies to term Why? We don't really know, but the mule is a marvellous experimental animal in this context. In an interspecies cross like the mule one would always expect marked differences between the two parents' white cell antigens, and on the analogy with humans, habitual abortions should be rare. Are they? Again, we simply do not know. Experiments in pure horse pregnancies would also be rewarding, because one could relate the rate of abortion to the degree of similarity in parental HLA antigens; the group of antigens most critically associated with rejection. Racehorses, being relatively inbred, are likely to be more compatible, and so more likely to abort. There might be a fortune to be made giving racehorses transfusions of white cells, but I feel that owners would sooner risk their wives than their animals. Skin grafts are like blood transfusions in some respects; they too challenge the recipient's immune system. Could mule pregnancies be interfered with by giving the mare a skin graft from her prospective donkey consort? <2How infertile is infertile?>2 Hybrids such as the mule are generally unable to have offspring, but in a less restricted sense they are fertile. She- mules show behavioural signs of ovulation at irregular inter- vals, and one can find egg follicles and corpora lutea, the bodies formed after the follicle has ruptured to release the egg, in a she-mule's ovaries. But do the follicles actually contain eggs? One would assume that they might but Kurt Benirschke and Margaret Sullivan, while at Dartmouth Medical School in New Hampshire, could not find a single egg in the 47 pairs of mule ovaries that they examined. This led S. Ohno at the Sloan-Kettering Institute in New York to the rather unlikely conclusion that the mammalian ovary must be capable of inducing oestrus cycles even in the complete absence of eggs. The matter has been made much clearer by the work of M. J. Taylor and Roger Short. They studied the development of germ cells in the ovaries of many fetal and neonatal mules and hinnies and compared it with development in the parental stocks. They found that in the hybrids the germ cells apparently migrated into the fetal gonads normally, and their early cell divisions proceeded normally. But the cells usually died when they underwent the reduction division (meiosis) necessary to produce gametes with half the parental chromo- somes, so that the older the fetus the fewer the germ cells found. The reason for this is that horse and donkey chromo- somes are dissimilar and almost completely unable to pair up. Meiosis cannot norrnally occur unless the chromosomes form so-called homologous pairs; despite this, meiosis did occasionally occur and a few normal-looking egg cells appeared. Why this should be so is not clear. Perhaps the DNA of the mule germ-cells mutates back to the parental forms or, more speculatively, as Taylor and Short suggest, borrows chromatin (chromosomal material) from a neigh- bouring cell. This might happen for some clumps of primor- dial germ cells are known to form intercellular bridges so that they exist as a syncytium (fused cells, sharing several nuclei). The donkey has 62 chromosomes (31 pairs) of which 38 are joined in the middle (metacentric). The horse has more chro- mosomes, 64 (32 pairs), but only 26 are metacentric. This means that while the mule and hinny both have 63 chromo- somes (31 + 32) many pairs are unevenly matched. This explains why, even though gametes may occasionally be formed, male and female mules (and hinnes) are mutually infertile. The chromosomes are simply unable to pair up. Aristotle commented on the mule's infertility in 350 BC, but since then there have been sporadic accounts of fertile she- mules--particularly, in retrospect, on some special occasion like the birth of Julius Caesar. <1"Cum mula peperit">1 (when a mule foals) is the equivalent of our own "once in a blue moon". The Polish scientist, W. Bielanski, reviewed all the avail- able reports of foaling in mules and hinnies since 1527--about 30 in she-mules and 2 or 3 in she-hinnies. As far as is known there are no reports of fertile male mules, though they are far from impotent. The problem, once again, is the dissimilar chromosomes preventing pairing and mei- osis, although, as with she- mules, there is some scant- evidence of normal pairing and the occasional mature spermatozoon. I will now discuss three of the cases of allegedly fertile she-mules, bearing in mind that no serological or chro- mosomal analysis was done, they must each be regarded as "anecdotal". The most famous was "Old Bec", a mule living in the United States in the 1920s. She produced two offspring: one, sired by a donkey, was a typical female mule who, unlike her mother, proved to be sterile; the other, sired by a stallion, was a horse. This back-crossed son of Old Bec was fertile, fathering a number of colts and fillies, and he also served as a popular saddle horse. None of his offspring showed any sign of its donkey ancestry and this led W. S. Anderson at the University of Kentucky to conclude that "this son of 'Old Bec' had originated from an ovum with no chromosomes from his grandsire the jack". Much more recently, in 1981, there was a newspaper report of a Chinese she-mule who gave birth to a foal in Honan Province; the sire was a donkey and the offspring a mule like its mother. I heard about the animal from a Chinese scientist and all seemed set for progress. We discussed cytological and serological studies and obtained a grant from the Great Britain-China Centre for a Chinese geneticist to visit Edinbugh. She was to bring samples from the parents and their offspring so that she and Dr Ann Chandley could analyse and discuss them together. Bureaucracy, however, won the day. After much laborious correspondence we re- ceived from China the following: "We believe that no one outside of this country will have access to the mule and her foal in Honan Province because such matters will have to be approved by the authorities here. Actually the cooperative project is presently under consideration by the authorities here." It still is! Our prospective visitor bowed to the inevita- ble and wrote to us: "Owing to procedure for obtaining a visa usually taking a long time it seems impossible to start our work at the date you suggested. It would be, therefore, better to extend the date until next spring." The Chinese, as is well known, have all the time in the world; "next spring" has come and gone. The third report I know of came from the Johannesburg <1Sunday Times>1 of 14 February, 1982, and was sent to me by a medical colleague. I wept at the loss to science caused by the slaughter of the mother, but soon dried my eyes as Lorraine Travis, the honorary secretary of the British Mule Society, said she thought that the foal in the photograph was a donkey and not a mule, and so did several of her knowledgeable friends. This highlights one of the perennial difficulties of "fertile" mules; mules and donkeys are not always easy to distinguish, and even some horses have long ears. Further- more, when horses, mules and donkeys are pastured together a horse foal may accidentally bond to a female mule and be thought to be her offspring. Confusion is heightened if the mule then lactates, which she may. The South African case remains interesting, and I asked my doctor friend for clari- fication, but so far he has not been able to get any further information. These three cases are of the best, and none of them is particularly convincing. One should therefore be sceptical about fertile she-mules, especially because Benirschke and his colleagues showed by examining her chromosomes that one claimant was in fact a don- key. Nevertheless, there is a strange but consistent pat- tern to all the reports of off- spring; fertile she-mules mated to donkeys always produce mules and those mated to stallions always produce horse foals. Con- versely, a female hinny mated to a donkey always produces a donkey. (There are no reports of female hinnies successfully pro- ducing offspring after mating with a stallion.)  Chandley deals with these observations neatly by in- voking something called "affinity". The idea goes back to Anderson's work in the 1930s, and Chandley's explanation is that very occasionally the whole set of donkey chromosomes might cling together and pass to one of the egg cells while the entire horse set goes to the other. The theory is that only the maternal chromosomes permit a viable egg to develop in the hybrid; in the mule this is the horse set, while in the hinny it is the donkey. D. Michie, professor of machine intelligence at Edinburgh University, has discovered a somewhat similar state of affairs in a hybrid mouse, and R. A. Fisher suggested the term affinity to describe the phenomenon. In all cases the explanation is that there is some sort of physical attraction between the centromeres of similar ancestry. Centromeres are portions of the DNA that hold the two halves of a divided chromosome together, and it is reasonable to suppose that the centromeres of a given species would be more like one another than like the centromeres of another species. They might therefore have a physicochemical affinity for one another. If the explanation of affinity is true, then it is possible that spermatozoa produced by a male hybrid would contain only the paternal chromosomes, and will therefore carry the Y sex chromosome, a donkey-Y in male mules and a horse-Y in male hinnies. This is a testable prediction. There are other interesting aspects to the cells of mule and hinny, for example the question of sex determination. Female mammals have two X chromosomes, one from the mother and one from the father, while males have an X from the mother and a Y from the father. In females, one of the X chromosomes is switched off early in development, but not before the fertilised egg has divided several times. According to Mary Frances Lyon, who discovered that only one of the X chromosomes is active in female mammals, it is completely random which particular X chromosome is inactivated in any given cell, so an individual female is made up of clones of cells in which either the maternal or paternal X chromosome has been switched off. The X chromosomes of horse and donkey can be distinguished and can be traced in mules and hinnies, and they support Lyon's idea. Furthermore, on the X" chro- mosome there is a gene for the enzyme called <1G6PD>1, and again the horse version can be distinguished from the donkey version. When you look at <1G6PD>1 in female mules and hinnies you find evidence of the two parental sorts of enzyme, but there is an interesting hint that the donkey version is selected against. In no study was the donkey <1G6PD>1 predominant. There is obviously still much to be learned from a study of the two hybrids. I cannot end without mentioning my own favourite dis- ease, haemolytic disease of the newborn (HDN). In humans this is called Rhesus disease, and there is a similar disease that affects horses and mules. HDN results from blood group incompatibility between mother and offspring. In humans, for example, the mother is Rhesus negative and the fetus Rhesus positive (derived from the father). In man and horse, without treatment the offspring becomes jaundiced and sometimes dies. In the horse, as in humans, the first offspring is not usually affected. The likely reason is that the mother becomes immunised to the foreign antigens only by fetal bleeding across the placenta at or near the time of birth. In the foal, the disease is of no great importance because the mother's antibodies can reach the foal only via the colostrum (the first milk secreted by the mother after birth) and not, as in humans, across the placenta. This means that the toxic reaction between the mare's antibodies and the foal's antigens is easily prevented; one simply covers the mare's teats, or muzzles the foal, for 24 hours and provides colostrum from a non-immunised mare instead. In the mule and hinny, however, the disease is full of in- terest. Although the blood groups of the parents are almost certainly incompatible, one would expect diseased foals to be very exceptional because the first offspring is rarely affected. But the books say that 8 per cent of mule foals suffer HDN. We do not know how many mares have a second hybrid foal, but even so this figure seems unusually high. Perhaps, as in humans, immunisation occasionally occurs during the first pregnancy, and the 8 per cent refers to these foals. Research on HDN in foals is still therefore wide open, and for a change there is the prospect of animals benefiting from advances made in the study of human medicine. But science and the mule are still far apart. The problem of fertility is as unsolved as it was in the time of Aristotle, and the principal bugbear is lack of cooperation. Bureaucracy seems to block the Chinese sources, which with their huge mule farms must have a great deal of information. The South African evidence may well be inaccurate. And the British Mule Society, of whose executive committee I am chairman, is composed mainly of mule lovers who are reluctant to lend their animals for observation and experiment. All in all, the mule situation is the exact opposite of that in medicine where there are queues of humans waiting for science to help them. In the mules, by contrast, science is waiting for the animals, and all the hypotheses are testable by simple procedures. Can <1New Scientist>1 please help? <2MONITOR>2 <2Protons live longer than theories>2 RESULTS from an experi- ment in a salt mine 600 m below ground in Ohio have extended the known lifetime of the proton by a factor of 10. While it is reassuring to most people to learn that one of the basic building blocks of our bodies and the world we inhabit is more nearly permanent than we knew before, the latest data may provide problems for some theorists. That is, for the physi- cists who are trying to establish a single theory that embraces all the four fundamental forces known to take part in shaping the physical Universe as we know it. Support for the so-called "electroweak theory that links two forces, the electro- magnetic force and the weak nuclear force, has recently come from experiments at CERN, the European centre for particle physics. These seem likely to have discov- ered the W-particle, which according to electroweak theory must exist <1(New Sci->1 <1entist,>1 27 january, p 221. But theorists have already been busy for the past few years working on schemes that incorporate a third force, the strong nuclear force, with electroweak theory. One prediction of many of these schemes is that the proton must be unstable, decaying eventually to electrons and protons. The average lifetime predicted for the proton depends on the specific theory but most give values in the region of 10 years. The only way to test these predictions in the space of a few years is to observe a sufficient number of protons and see if a few decay. The experiment in the Morton salt Mine in Ohio is one of a number set up around the world to do just this. The apparatus in the salt mine, designed mainly by physicists from the Universities of California (Irvine) and Michigan and the Brookhaven National Laboratory in New York, is deceptively simple. A specially-mined hole lined with plastic forms a tank for nearly 10 000 tonnes of water, or in the region of 10s protons. The water is viewed by light- sensitive detectors designed to pick up the so-called Cherenkov light emitted when electrically-charged particles travel faster than light does through the water. If a proton decays, its products should produce tell-tale patterns of Cherenkov light on the walls of the tank. In a flurry of seminars both in the US and in Europe members of the team have presented the first results from the experi- ment. The resarchers have looked for a specific decay of the proton, namely into a positron and a neutral pi-meson (n). After 80 days of observing they have found no proton decays of this kind. This absence of evi- dence translates into a lower limit for the proton lifetime of 6.5 x 10s years. Earlier results, however from an experiment 2300 m deep in the Kolar Gold Fields near Bangalore in India suggested that the proton <1is>1 unstable, with a lifetime of 7.5 X 10s years. This experi- ment, by scientists from the Tata Institute of Fundamental Research in Bombay, and the Universities of Osaka and Tokyo in Japan, contains 140 tonnes of iron inter- laced with detectors to pick up possible products of proton decay. The researchers have found three occasions on which they claim the signal in the detectors is consis- tent with the decay of a proton. A third experiment, this time in Europe, in the Mont Blanc tunnel, has also recorded one possible proton decay. This apparatus, set up by physicists from Frascati, Milan and Turin, contains 134 tonnes of iron. The result, reported last summer corre- sponds to a lifetime of about 10s years, once the observing time and total number of protons are taken into account. However, all the experiments face prob- lems due to neutrinos, neutral particles originating from outer space, which can travel easily through the Earth around the apparatus. These neutrincs can interact in the detector and mimic a proton decay; many physicists remain unconvinced that the "observed" proton decays are not sim- ply due to neutrinos. If the results from the Morton Salt Mine are correct they seem to spell trouble for one of the simplest "grand unified" theories, known as SU (5). Work presented at last summer's high-energy physics con- ference in Paris gave an upper limit of 2.25 x 10s years for a proton decaying into a positron and a . If this were correct the experimenters studying the data from the salt mine should have already discovered seven proton decays. The fact that they have seen nothing is by no means an immediate death blow for all grand unified theories. The SU (5) model is already in difficulty in dealing with the creation of particles in the early Universe. Other unification schemes suggest that other modes of proton decay should be more common, such as the decay into a muon and two . No doubt theorists are up to the challenge presented by the new results and will come back in time with new estimates, before they declare the proton stable. [] <2Twin-studies uncover diabetes marker>2 A NEW study of insulin-dependent diabetes in identical twins has brought doctors closer than ever to being able to predict its development in people thought to be at risk. Insulin-dependent diabetes is the most severe form of the disease, and is now con- sidered to be an auto-immune disorder in which the cells of the pancreas responsible for producing insulin (the beta-cells) are destroyed by the body's immune system. If doctors could know for certain which indi- viduals would develop the disease, they could treat potential diabetics before the process takes hold. Previous research has shown an associa- tion between diabetes and certain antigens coded for by the so called "major histo- compatibility complex". These antigens are expressed on the surfaces of the body's defence cells, the lymphocytes, and help them to recognise invading foreign cells. The antigens are called human lymphocyte A (HLA) antigens. In organ transplants an optimal donor would have an identical HLA complement to the recipient. Researchers had already recognised that two of the HLA antigens, designated DR3 and DR4, predispose to diabetes. With the help of 106 pairs of identical twins, Dr Colin Johnston and colleagues at King's College Hospital and st Bartholomew's Hospital in London showed that the risk of developing diabetes is far greater if a person has both DR3 and DR4 than if he or she has either antigen alone <1(British Medical>1 <1Journal, p 286, vol 253).>1 In 56 pairs, both twins had diabetes (that is they were concordant) and 50 pairs were discordant (only one of each pair had the disease). As expected, both sets showed a high prevalence of one or other of both HLA-DR3 and HLA-DR4 antigens com- pared with controls. However there were almost double the number of concordant twins who had <1both>1 DR3 and DR4 antigen than there were discordant twins with both antigens. Most discordant twins had one or other antigen, Identical twins who are discordant for diabetes start out with the same sus- ceptibility; it is only the action of an envi- ronmental stimulus on one twin, and its absence on the other that makes them dis- cordant. But this study has, for the first time, clearly demonstrated a genetic differ- ence between concordant and discordant identical twins. Twins with both DR3 and DR4 antigens appear to get a double dose of susceptibility to diabetes. The hope is that other markers can be identified, which when pooled together will enable doctors to predict, with great cer- tainty, individuals who will develop insulin-dependent diabetes. Once this is done, attempts can be made to curb the body's tendency to destroy its own beta- cells, using immunosuppressive drugs. [] <2X-rays repeal new angle on quasars>2 RECENTLY analysed results from the now defunct X-ray observatory sat- ellite Einstein are casting doubt on the most-popular explanation for the very small, rapidly varying quasars called BL Lac objects. Many astronomers have thought that these very distant and power- ful sources are simply quasars that we see at a special angle, but the new statistical analysis seems to rule this out. Quasars are the highly energetic cores of distant galaxies. Many of them shoot out beams of high-speed particles in opposite directions, which appear to radio telescopes as "jets" of emission. Some astronomers have convincingly argued that a BL Lac object (a clumsy terminology referring to the first of this class to be discovered) is simply a quasar with one of its beams pointing straight at us. This attractive picture relates the strange BL Lac objects to quasars in a straightforward way, and offers the exciting possibility of looking, in a BL Lac object, deep into the heart of a quasar--possibly down to the central powerhouse where a quasar produces as much power as hundreds of galaxies in a space no larger than the Solar system <1(New Scientist,>1 vol 95, p 364). If this theory is correct, then it is possible to predict the relative numbers of quasars and BL Lac objects we should expect to detect. Naively, we would expect many more ordinary quasars, because there is only a small chance of a beam pointing straight at us: but the calculation must also consider the fact that BL Lac objects would on average appear to be brighter than other quasars (because the doppler effect bright- ens a beam coming towards us), and so we would tend to pick up more of them. Daniel Schwak of the Harvard- Smithsonian Center for Astrophysics and William Ku of Columbia University have now checked the predictions against the statistics of BL Lac objects that emit X- rays, as found by the Einstein observatory. They have determined the number of BL Lac objects per unit volume of space, and compared it with the space density of qua- sars and other types of active galaxies (sub- mitted to the <1Astrophysical Journal).>1 The results are startling. They find many more BL Lac objects than the theory pre- dicts. Even allowing for the fact that not all BL Lac objects produce X-rays, Schwartz and Ku conclude that the statistics rule out the idea that BL Lac objects are simply ordinary quasars seen "beam-on". One possible answer is that a quasar pro- duces not just one beam, or one pair of oppositely-directed beams, but multiple beams. This would raise the chance of see- ing a beam end-on. Another possibility is that all quasars and BL Lac objects are beamed roughly towards us, and that some- thing else distinguishes them--something that so far remains hidden in the enigmatic central powerhouse. [] Indian gum makes healthier bread SO-CALLED slimming or high-fibre breads are very little better than the much-maligned sliced white loaf, on the basis of "calories" per ounce (or kilojoules per kilogram). But guar bread, newly- created by British food chemists, not only has a high fibre content but actually has 25 per cent fewer calories per ounce. The new bread, which looks and tastes like ordinary bread, can help diabetics and people with high levels of cholesterol in their blood, according to Edward Apling of Reading University and Peter Ellis of London University's Queen Elizabeth College <1(Chemistry and Industry,>1 1982, p 950). Guar gum comes from the endosperm of the Indian cluster bean <1(Cyamopsis tetra->1 <1gonorobus)>1 which produces the gum to store polysaccharide. Guar is cheap and plentiful and is already used in some foods as a natural stabiliser. Furthermore, some forms of dietary fibre reduce blood choles- terol, and guar gum does this even more efficiently than the archetypal fibre, wheat bran. But making bread with large amounts of guar--more than 10 per cent--creates prob- lems. It is a gum and in water produces a very viscous solution even at low concen- trations. So much more water is needed to get a workable dough. Moreover the baked bread tends to collapse on cooling or to be uncooked in the centre. But bread with 5 per cent guar bakes well and tastes like ordinary bread. With 10 per cent guar, tasters noticed a difference but still found the bread quite pleasant. The 10 per cent guar loaf has 25 per cent less digestible carbohydrate, and hence 25 per cent fewer calories, than white bread, yet it has three times more fibre. The bread wards off hunger for as long as the same weight of ordinary bread despite its lower starch value. And guar improves the texture of brown bread. Food chemists have investigated guar bread in the hopes of finding a palatable way of increasing the fibre in the diet of diabetics. Their success has wider impli- cations. Guar bread appears to be the answer to the baker's prayer; it counters the popular belief that all bread is fattening and that white bread is too refined to be healthy. Guar bread's twin features of higher fibre and fewer calories may be the best thing to have happened to the bread industry since sliced bread. [] <2Morels are tamed at last>2 MOREL enthusiasts rejoice! No longer you have to grovel through the woods each spring in hopes of stumbling across a few of these delectable fungi. Ronald Ower of San Francisco state Uni- versity reports that he has accomplished the hitherto impossible task of obtaining a fruiting culture of the morel <1(Mycologia>1, vol 74, p 142). Morels, simply put, are the Most Deli- cious Edible Fungus. Truffles are merely an expensive and tasty seasoning; but morels are more sub- stantial, to be relished intact, whole and good. As with truffles, however, morels have until now resisted Joining the ranks of domesticated fungi. This would not be too great a bother if morels could be col- lected in the wild for a reasonable length of time each year, but the fruiting bodies of the morel make only a brief appearance, sometime between March and May. This short fruiting season has inspired a rich folklore regarding the optimal time to stage morel hunts. Some say that hunting in old burned-over sites when the oak leaves first appear is a good and fruitful strategy, but others insist that morels are best col- lected in old apple orchards at the time when the lilacs bloom. In any case, chances for stocking the larder with a de- cent supply of morels are slim, especially for the novice. Morel hunters in-the-know rarely reveal the locations of good hunting grounds, and the abundance of any year's crop seems to depend upon a great many variables such as: how cold a winter preceded, how gradu- ally did temperatures warm from winter to spring, does the soil have adequate mois- ture? The morel, like gold, is where you find it. But all of that may change. Growing his fungal mycelium in a concoction of wheat berries under a strict regimen of light, temperature and humidity, Ower re- ported a harvest of 16 mature morel fruiting bodies. Enough for one good meal, anyway. We can only wish this enterprise con- tinued success and hope that it will soon put morels on the table year-round. []  <2Sleeping sickness lurks in blood vessels>2 ONE OF the puzzles about African sleeping sickness and the related dis- ease, nagana, which affects cattle, is the way in which a patient suddenly relapses several months after apparent success with chemotherapy. Now Dr David Omerod of the London School of Hygiene and Tropical Medicine and Dr M. O. Abolarin of the Kwara state College in Nigeria have discovered what is almost certainly the answer to the puzzle. The trypanosome parasites that are responsible for the disease survive inside the cells of the choroid plexus, the network of vessels through which blood is filtered into the cerebro- spinal fluid. The resting or cryptic stage of the trypanosome's lifecycle is actually in- side the cells of the epithelium of the choroid plexus. So far trypanosomes have been found only in the choroid plexus of mice. But there is now some strong indirect evidence that trypanosomes also lurk in the human choroid plexus. Ormerod's working hypothesis is that the parasites migrate there to avoid the host's immune response, which cannot recognise foreign invaders that have crossed the blood-brain barrier. The crytic stage in the choroid plexus may also give the "tryps" time to alter their surface antigens, and so escape destruction by the immune system; the trick that has, to date, made it impossible to construct vac- cines effective against them. The ability to hide in the choroid plexus would also ex- plain why some drugs are of limited value in chemotherapy for sleeping sickness. Their molecules may not penetrate the blood-brain barrier. Now the hunt must be on for tryp-killing drug molecules which will actually pene- trate into the choroid epithelium. Arsenical compounds are one possibility. [] <2Spanish oil syndrome may be auto-immune>2 HOW DID contaminated cooking oil poison and kill so many spaniards in 1980? A recent theory implicated adulter- ation with aniline, a common but highly toxic industrial chemical. This was sup- posed to lead to extensive membrane dam- age caused by a highly reactive chemical species, called "free-radicals" <1(Nature,>1 vol 298, p 608). Two researchers at the presti- gious Salk institute in San Diego, Califor- nia have proposed an alternative theory: that the Spanish oil syndrome is a violent auto-immune disease (that is, the body at- tacks itself) triggered by an elusive bacte- rium called <1Mycoplasma pneumoniae.>1 Bob Root-Bernstein and Fred Westall write in <1Nature>1 (vol 301, p 178) that the anilide free-radical idea has certain snags. Compounds that neutralise free radicals have no effect on patients; also, many of the Spaniards consumed the poisoned oil with- out ill effects. On the other hand, My- coplasma infection was found in an abnor- mally high proportion of people with the syndrome. The normal symptoms are pneu- monia and bronchitis, but occasionally severe reactions set in, resembling those seen in Spain. The two researchers propose that the contaminated oil acted as an "adju- vant"--it made those rare reactions, com- mon. An auto-immune disease ensued, with destruction of nervous and vascular tissue. Should this be proven, it will be a new complication of a conventional disease. Mycoplasma--also found in Britain as a cause of some forms of bronchitis--can usually be controlled by the antibiotic erythromycin. [] <2Big-billed parrots avoid a fight>2 ANIMALS in dispute over some valuable resource, like food or mates, should behave like rational humans playing games, John Maynard smith of the Univer- sity of Sussex first suggested in the early 1970s. When animals are equipped with nasty horns, talons or beaks capable of inflicting great damage on a sparring part- ner, they should evolve ways of settling disputes peacefully. Convincing evidence that animals actually do operate this way comes from James Serpell of the University of Cambridge <1(Animal Behaviour,>1 vol 30, p 1244), who has been studying the aggressive behaviour of nine species of tropical parrots of the genus Trichoglossus. Some of these lorikeets have small bills that are capable only of pinching the skin of human handlers, while other species can easily draw blood and even splinter wood. James Serpell compared their "firepower" with the complexity of their aggressive dis- plays and found that the better equipped the birds were to do damage to each other, the more complicated and prolonged their displays. And the larger a parrot's bill, the less likely it was to attack a mirror reflecting its own image (a standard ploy which con- vinces most birds that they are confronted by a particularly nasty-looking aggressor). Why does threat behaviour become more complex as fighting becomes more dangerous? Richard Dawkins and John Krebs of Oxford University suggested in 1978 that complex displays allow an animal to escalate threats gradually. Big parrots need a greater range of signals, according to this theory, so that they can express more stages in the escalation before resorting to costly violence. But lorikeet displays, Serpell found, do not seem to be graded in intensity; the large-billed birds use, instead, a greater variety of discreet gestures but in a rather haphazard order. Serpell suggests that the parrots are trying to startle their rivals with these varied displays, Switching between a large number of gestures in an unpredict- able way may be more intimidating than repeating a few cliched movements over and over again. These complicated displays could even honestly advertise a bird's mettle. The superior parrot may be especially good at "dazzling rivals with the unexpectedness, speed and intricacy of its displays"--such a brilliant performance might be too m uch for the inexperienced or debilitated parrot. [] <2Set a parasite to catch a>2 <2parasite>2 MISTLETOE, well-loved by Christmas revellers, has great potential in an- other field of human endeavour--pest con- trol. In the foothills of the Himalayas an answer to the destruction of valuable trees by mistletoe has been found--in the form of a second mistletoe species capable of hyper- parasitising the destructive parasitic form. The discovery was made and is now being successfully used by Y. Pundir of the Bot- any Department of the Dehradun College, Uttar Pradesh, India. (<1Weed Research,>1 vol 21, p 233) <1Scurrula cordifolia>1 is a mistletoe that at- tacks valuable fruit and timber trees, killing them or making them too deformed for commercial purposes. <1S. cordifolia>1 had traditionally been confined to the Western Himalayas, but in the 1970s it spread to the Sivalik Hill region. There it affected many trees and shrubs, including the valuable timber tree <1Ougenia oojeinensis.>1 Various eradication methods, particu- larly herbicides, have been tried, but high costs and the difficulty of spraying vast forests Limit their usefulness. In 1972, Pundir observed <1Viscum>1 <1loranthi,>1 another mistletoe, hyper- parasitising <1S. cordifolia.>1 During the fol- lowing eight years the hyperparasite has spread rapidly and infected most of the <1S.>1 <1cordifolia>1 in the area under study. Such hyperparasitism is well-known among Loranthaceae, the mistletoe family. The sticky seeds of <1V. loranthi>1 adhere to many plants, but only those attached to other mistletoes develop. After about 12 months the host mistletoe is usually either dead or severely weakened. Survival of the host mistletoe depends on two factors: its age and the severity of hyperparasite attack. Younger branches of <1S. cordifolia>1 are much more susceptible to damage than older branches. But susceptibility can be influenced by the severity of infection; a younger branch supporting a small number of hyperparasites can outlive a heavily in- fected older branch. Pundir has found that a large number of <1S. cordifolia>1 have been killed by the hyper- parasite <1V. loranthi,>1 resulting in a sharp de- cline in the <1S. cordifolia>1 population, An additional factor in favour of this system is its specificity. Apparently the hyperparasite infects only mistletoe and so <1V. loranthi>1 can be safely introduced into new areas, where it will attack mistletoes without para- sitising any other plants. [] <2TECHNOLOGY>2 <2Britain sows the seeds for a new chip industry>2 BRITISH scientists and businessmen are trying to break into a vital slice of the semiconductor industry which foreign companies now dominate. The business is the market for the materials that print patterns of circuits onto tiny chips. Chip makers want to shrink their chips to meet the demand for faster electronic devices and computers. They need new lithographic materials to do this and British polymer chemists can provide them. The Science and Engineering Research Council has desig- nated electro-active polymers an area of special interest. It intends to spend #1 million over the next five years on this, and other polymer research. It sponsored a meeting at Didcot, near Oxford, last month to bring university researchers and semiconductor manufacturers together to discuss new lithographic materials. In the semiconductor industry, light- sensitive materials--or "resists"--transfer intricate circuit designs from "masks" onto silicon wafers. When the resist-coated silicon is exposed to light and developed, it imprints the pattern in one of two ways. In positive resists, areas affected by the light become easier to remove after devel- opment. In negative resists, the reverse hap- pens. Today's resists can define features as small as 1 or 2 micrometres. But computer companies want faster chips, and faster means smaller. John Speight, of British Telecom, told the meeting at Didcot that designers aim to reduce dimensions to 0- I to 0.2 micrometres in the next decade. But this requires better optical processing tech- niques and materials. New methods, such as ultra-violet, electron beam and X-ray lithographics, and etching with ion beams, may also be necessary. Most optical resists are developed by mixtures of solvents which wash away the more soluble material left after exposure. But the resist left behind also absorbs the solvents, and swells up. This limits the resolution achievable. Negative resists suffer the most, with resolution limited to 5 micrometres. The ideal answer would be "dry" development. One technique on the way involves ion beams etching the exposed resist. But ion etching has its disadvantages. It creates a lot of heat, so companies using it will need materials with a greater thermal resistance. The heating can also cause the resist to form volatile materials, which contaminate the ultra-clean environment of the chip factory. Charles Leece, of Ferranti, emphasised industry's need for resists that give the same results every time, and that are free of impurities larger than 0.1 micrometres. Ferranti uses a proprietary posi- tive resist to process its chips. Leece says he is prepared to go anywhere in the world to obtain a reliable resist. New lithographic techniques, such as electron-beam or X-ray methods, require their own spe- cial resists. Britain already has a foothold in this market--the only home-grown resist avail- able is an electron-beam resin that Philips developed in the UK. Other products from abroad are coming onto the market, but the Didcot meeting agreed that there is scope for im- provement. Also, no specially developed X-ray resist is avail- able in Britain. Another opportunity for research is in developing plastics for packaging chips. The materials in use today, such as silicones and epoxy novolak resins, are per- meable to water. This can leach out im- purities, such as sodium, from the plastic, and cause corrosion inside the chip. Indus- try needs new, impermeable plastics for "go-anywhere" chips. John Speight says that in some cases, the package is more ex- pensive than the chip inside. Both the scientists and the industrialists said they were pleased with the Didcot meeting. The next step will be to set up collaborative research projects, under the Science and Engineering Research Council. The council has already set up a working party on resists, chaired by Ron Lawes. It is also appointing a coordinator to promote research on electro-active polymers, and plans to run further workshops later this year. [] <2What next>2 NEW developments in resists will solve only one of the problems that face the designers of smaller chips. According to Professor Otto Folberth, of IBM West Germany, the others will be the thermal and electrical barriers. Most of today's chips are cooled by air. But as designers pack more and more circuits into a given space, other methods become necessary (see next Box). Another promising development is called forced liquid cooling, in which water at very high pressure is forced through tiny fins etched on the chip. The electrical problem arises from the finite time it takes a signal to travel across a chip. The speed of the whole chip is restricted by the time it takes a signal to travel the longest distance. To- morrow's large and complex chips will consist of three-dimentional modular arrays, rather than today's "spaghetti" wiring. []  <2New chip is a cool customer>2 A NEW American semiconductor could overcome one or the biggest hurdles posed by the ever-diminishing size of inte- grated circuits. It could open up a whole new range of products, especially portable equipment. The big problem with today's chips, which squeeze more than 120000 transistors into less than a square centi- metre of silicon, is heat. If heat cannot be dissipated circuits misbehave. Water cooling eliminates the problem in main- frame computers, but smaller machinery must find an alternative. The Intel Corporation claims to have overcome the problem by combining the attributes of two of its earlier semi- conductors. One has low power require- ments, thereby dissipating little heat, the other has high-density circuitry. By combining the two, the new chip dissipates one tenth as much current and heat as the high-density chip alone. Intel boasts that CHMOS (com- plementary, high-performance, metal- oxide semiconductors) will allow inte- grated circuits to shrink toward the goal of very large-scale integration (VLSI). Very large-scale integration will be necessary to achieve goals such as complete computers on one chip. They should be far more reliable than today's circuits. The new chip goes on sale this year in two microcontrollers which will be capa- ble of going into "idle mode" when not in use. This further reduces both the power required and the heat generated, but with- out any threat to vital data. Intel claims that CHMOS will spawn a new generation of compact, portable and battery-driven electronic devices such as hand-held medical instruments, portable computer terminals, lightweight video recorders, and new "senses" for industrial robots. Military uses include controlling small missiles and portable radios. [] <2Patent lather>2 FRENCH inventors are being urged to gird themselves for an economic war against foreigners who steal their ideas. A campaign of advertisements placed by the French government, uses the slogan "Economic war arm: yourselves". The advertisements show an office packed with industrial spies hot on the trail of technological secrets The advertisements tell inventors and small companies to make sure they protect their intellectual property with patents and trade marks. A recent survey showed that two-thirds of French small businessmen had never even heard of patents or trade marks. For every Frenchman who patented an invention in 1980, the British patented two, the West Germans four, the Ameri- cans six and the Japanese 15. [] <2Industry eyes Americans weather satellites>2 PRESIDENT REAGAN is weighing up a report which would hand control of the US's weather and remote-sensing satellites to private enterprise. According to sources in Washington, officials in the Department of Commerce decided at the end of last year to recommend this strategy to the president as the most effective way of relinquishing responsibility for the US's Landsat system. Landsat is a series of satellites, the first of which entered orbit in 1972, They scan the Earth to provide data about, for instance, crop growth and geological deposits. The latest, fourth, Landsat was launched last year. The American government has made the data available at negligable cost to users around the world and, in recent years, has become concerned at the cost. The best solution, so officials have decided, is to "privatise" the system, and, along with it, the series of weather craft on which the world relies for much of its meteorological information. The US oper- ates five weather craft, three in geostation- ary orbit above the equator while the other two cover the whole globe. Data from the weather craft are made available for nothing to other governments under international agreements. In return countries in, say, western Europe or Japan, give to the US information from their own satellites. This practice would have to continue, so the government would have first to buy the data from whoever ends up operating the craft. The front runner in any bid for the remote-sensing and weather satellites is Comsat, the Washington company that already runs a series of communications craft. Comsat has offered to buy both systems from the government for around $ 300 million. By reducing ground stations and cutting staff, the company thinks it can run both sets of satellites more efficiently. To cushion the firm from immediate financial problems, Comsat has asked the government to guarantee that it will continue to buy data for 15 years. Initially the administration would be asked to fork out about $325 million per year for Land- sat and weather infomation. After this, the annual payments would decrease. Paul Maugan, the head of Comsat's Earthstar programme, says this arrange- ment would save the American taxpayer about $ 1000 million over 10 years. He says that with better marketing, the firm would increase sales of Landsat data abroad, launching new satellites when necessary. According to Maughan's plans, Comsat would also sell meteorological information to particular groups such as farmers. Not everyone shares Maughan's opti- mism that the deal will go ahead. For one thing, the government may baulk at giving the financial guarantee. Further, even if Reagan approves, Congress would have to enact the necessary legislation--and may not think that handing over the craft is in the nation's best interests. Other firms are waiting in the wings, ready to step in with their own bids for Landsat. (Few are interested in the meteor- ological craft, however.) Fairchild Indus- tries General Electric and Hughes are among the household names that have talked to the Department of Commerce about Landsat. Another--much smaller--firm involved in the discussions is American Science and Technology Corporation which plans, even if it fails in its bid for Landsat, to launch a rival set of satellites from the mid 1980s, The craft would scan the Earth with rela- tively low resolutions. [] <2Europe's launcher may miss the bus>2 EUROPE'S X-ray astronomy satellite Exosat will almost certainly be launched on an American Delta rocket because of delays to the European launcher Ariane after its last failure. The European space Agency (ESA) wants to launch Exosat before mid- summer, and its council has agreed to negotiate with the American space agency NASA to use a Delta. A team is already in the US discussing the technical problems, but there seems to be little difficulty in mating Exosat to a Delta rocket. The ESA has dropped the idea of swapping Exosat with the commu- nications satellite planned for the next Ariane launch L6, because Exosat requires a more complex launch into a transfer orbit with a subsequent boost from its own fourth-stage rocket. L6 is almost certain to be delayed until well after its official launch date in May. This means that L7 would be too late for Exosat, and ESA will have to use a Delta. ESA has already paid for a launch on Ariane, but it can transfer this money to cover the launch of the Giotto mission to Halley's comet in 1985. The council will decide finally on 23 February. Meanwhile in Britain, the Astronomy Space and Radio Board of the Science and Engineering Research Council has unanimously approved a new X-ray satellite as Britain's next big space science project. During the next year, scientists will evalute the proposal and begin informal discussions with possible inter- national partners. Then they will ask the research council for the #30 million they will need for the project. [] <2High rises aren't so damp>2 IF YOU WANT to live in the dampest homes in England, rent a house or flat privately. According to a report from the Building Research Establishment (BRE), 28 per cent of privately rented homes are likely to have severe damp, with a further 19 per cent suffering from "slight" damp. This compares with only 5 per cent of owner-occupied homes having severe damp, and 17 per cent of council homes. Two researchers drew their conclusions from a survey of a week's complaints about dampness at five local authorities. They scaled them up nationally, using the recently-published English House Condi- tion Survey as a back-up. It means that, out of 17 million dwellings in England, 2 million are probably very damp indeed. If Wales, Scotland and Northern Ireland have a similar dampness pattern, the figure rises to 2.5 million homes in Britain now seri- ously affected. Of this total, about 1.5 million are damp because of condensation. The survey--smaller than BRE had hoped for--looked at 269 complaints. If such a small figure does indeed give the national picture in microcosm, then it knocks a few favourite "facts" about condensation on the head. One is that the condensation problem is greater in homes built from the mid-1960s onwards. The survey, suprisingly, shows that high-rise flats do better than average, with the main offenders being terraced houses. Only 46 per cent of damp flats were damp because of condensation, compared with 66 per cent of the total complaints about damp.  The survey was not able to pick out a definite link between the type of heating and the degree of damp in a home. But it found that anything that produces water vapour--unvented tumble driers, for example--pushed up damp levels signifi- cantly. As one might expect, the kitchen was usually the dampest room in the house. The report is only one of a recent clutch showing the generally dreadful state of British housing. Just before Christmas, the BRE attracted attention with a report on the scale of defects in traditional homes. The findings were an unwelcome surprise for those who had attributed build- ing faults to high-rise and system-built housing. The BRE's report, <1Quality in>1 <1Traditional Housing,>1 looked at traditional low-rise housing mainly on council estates. It concluded that most of the mistakes were simply due to lack of care all down the line and not because of untried designs. About half the faults of the eventual 955 types collated were in the outer structure. One in five faults were faulty roofs, and a further fifth were problems with the exter- nal walls. Overall, two-thirds of the faults affected strength, stability, durability and weathertightness. The remaining third covered anything from thermal insulation and heating through to fire safety and maintenance problems. A breakdown of the trades involved in the faults appears to show bricklayers at the top of the blacklist. Between them, they accounted for 36 per cent of the 955 fault types, with carpenters and joiners not very far behind at 27 per cent. The next highest were plasterers and plumbers (6 per cent each) with roofers close behind at 5 per cent. However, the BRE is careful to point out that the table attributes <1types,>1 not numbers of faults to the trades concerned. And, with the present governments's aboli- tion of the local-authority Parker Morris housebuilding standards and its pruning down of the building control system, the standard of new homes may fall. England is hardly in a position to handle built-in problems with new and future housing stock. The English House Condi- tion survey, which the Department of the Environment published shortly before Christmas 1982, showed a sharp increase in the number of homes now needing #7000 or more spent on them to bring them up to an acceptable standard. Since the last time the survey was done (1976), the south East of England has had a dreadful 82 per cent increase in the number of unfit houses. Nationally, the largest number of homes in bad condition were owner-occupied, and probably reflect the difficulties that the retired home-owner faces today in trying to eke out a fixed income. This survey differs from previous ones in that the department brought in private surveyors to work with environmental health officers. Previously, health officers had done the entire survey. However, the results--far from presenting a more "acceptable" picture of English housing--bore out everything that housing experts had been warning the government about for the past few years of increasing housing cuts. To get itself out of its self-dug hole, the Department of the Environment claimed that the 1981 study's improved meth- odology simply showed that the 1971 and 1976 surveys had underestimated unfitness and disrepair. These figures had now been revised so that a truer comparison of the housing stock's condition could be made. This will be a great comfort, no doubt, to those who have to live in England's damp, ill-lit, unstable and semi-derelict housing. <2Deirdrie Mason>2 [] <2Seeing double>2 ENGINEERS in the US have developed a way of cramming two television programmes into a single cable channel. The General Electric company says the system, called Comband, will double the capacity of any cable TV system without noticeably affecting the quality of picture or sound. The device takes two pictures from the different video channels, and aligns them in time, so that the horizontal lines of one picture exactly match the horizontal lines of the other. The black-and-white and colour information in each adjacent pair of lines in each picture is then averaged to halve the total number of lines. The two "half-pictures" are transmitted down a single cable TV channel with normal bandwidth. The receiver separates the two interleaved pictures, to form two separate pictures, each with half the normal number of lines. But each line of the picture is the average of two lines in the original, so by repeating each line, the receiver creates two whole pictures. Although there is definitely some loss of vertical definition, General Electric says it is hardly noticeable because adjacent picture lines are nearly identical anyway. So averaging two adjacent lines, then using the averaged line twice, is an acceptable compromise. [] <2Flushed with pride>2 THE STRIKE at Britain's waterworks has been good news for a sheltered workshop in Watford. The workshop, which employs disabled people, has received orders for 1500 valves that save water in domestic lavatory cisterns. The valve was the brainchild of a private inventor, Harry skevington. The govern- ment's Building Research Establishment did the development work, and some 5000 are already fitted in homes. It can reduce the amount of water needed to flush a lava- tory by 40 per cent--and flushing accounts for over one third of the water consumed in Britain's homes. The valve, available in batches of 100, costs "1.15. It fits into conventional cisterns, and works by opening an air gap in the siphon as soon as the handle is released. This interrupts the flush, saving water. The only moving part is a simple valve, connected to the flushing handle, which blocks a PVC tube when the handle is pulled. [] <2Power scheme will raise the Dead Sea>2 <2Israel wants to generate hydroelectric power by pumping water under the desert to the Dead Sea. The>2 <2financial and engineering decisions have been made. Just the political and environmental questions remain>2 <2Geoff Sifrin>2 DETAILED design work will begin in the next few weeks on an lsraeli hydroelectric scheme that will shift 1.6 billion cubic metres of water per year from the Mediterranean to the Dead Sea. That is enough to raise the level of the largest land- locked stretch of water in the Middle East by about 0.5 m in 12 months. The idea has been around for 80 years. It will bring prosperity to the Negev Desert but Jordan has protested to the UN that the $1.3 billion scheme will also change the Dead Sea's ecology and affect the local potash production. The Dead Sea, the lowest point on the Earth's surface, lies 402 metres below mean sea level. Israel intends to use this head to generate up to 850 MW of electricity. The components of the plan are simple. A water intake will be built on the Mediterranean coast near the settlement of Qatif, some 13 km north of the Sinai border. The water will be pumped through a pipe passing 7 km under the cultivated fields of the Gaza Strip. It will then feed into a 22-km-long canal--some 25 metres wide and of an open, trapezoidal cross-section-- running east to the Judean foothills. An inverted siphon, a few hundred metres across, will be built to carry the sea water under the gorge of the Nahal Besor water course. A tunnel, 5.5 m in diameter and 80 km long, will then carry the water under the Beersheva and Arad regions to a plateau overlooking the Dead Sea. There, two reservoirs with a capacity of 4.6 million cu.m will store it when generating power is not needed. When power is needed, the water will drop 400 m down a pressure shaft to turbines at the level of the Dead Sea. The 1.6 billion cu.m of water discharged a year after switch on will be allowed to raise the Dead Sea for 20 years. After it has risen 11 m, to the "historical" level of 391 m below sea level, the discharge will be reduced to about 1.2 billion cu.m/year to stabilise the sea's depth. The advantage of hydroelectric generators is that they can be switched on and of easily, according to demand. Thermal stations burning coal, oil or nuclear fuel work 24 hours a day and their output is less easy to adjust. The Electric Cor- poration plans to use thermal stations (see Box A) to meet Israel's average electricity needs, currently 2200 MW, and to supplement this with hydroelectric power when demand peaks above this. The power available from the hydroelectric station will be at least 800 MW, eight hours a day for the first 20 years, thereafter falling by about 30 per cent. Major engineering challenges will be faced during con- struction. The 80-km tunnel, for example, will be among the longest anywhere. It will be concrete-lined and in places will be 500 m below ground level. Its route will pass mainly through soft rock and above deep-lying, brackish ground water. Three shafts will be sunk along the route to allow simultaneous excavation at eight faces. Detailed plan- ning and construction will take 9-10 years. Allowing for unseen problems, which are always a factor in the unsta- ble Middle East, it is likely to be 10-14 years before the power is switched on. It is not yet clear how the $1.3 billion bill will be met. The Israel Bonds Or- ganisation is to sell an extra $100 million in bonds over and above its regular sales as seed money for the project. Commitments have been made, so far, by 400 "canal founders" from the US, Canada, Western Europe and other countries. Each "founder" has promised to buy $100 000, or more, of bonds. The idea of exploiting the region's unique geomor- phology is not new. Many proposals have been put forward over more than 100 years. In 1850 an Englishman, Captain Wil- liam Allen, wrote a book, <1The Dead Sea --A New Pathway to India,>1 in which he sug- gested linking Haifa Bay, the River Jordan, the Dead Sea and Eilat by canal. The idea was largely motivated by political considerations, it would provide a sea route to the Far East in competition with the, then, unconstructed Suez Canal ex- pected to be controlled by the French. Theodor Herzl published his utopian novel <1Altneuland>1 in 1902. In it he envisaged linking the two seas to generate electricity, based on the proposals of the engineer Max Bour- cart, who wanted the canal to run from Haifa Bay, through the Bet Shean Valley, and then down the Jordan Valley. Bourcart also suggested constructing three power stations. In 1919 a Norwegian engineer named Hjorth proposed driving a tunnel through the Judean Hills. In 1925 Pierre Grandillon published a suggestion to bring sea water through the Jezreel Valley to the Jordan Valley, with two power stations <1en route.>1 The head of the Palestine Survey Commission during the British Mandate Period, engineer James Hays, presented a multi-purpose concept in 1943 for water management in Palestine. Water from the River Jordan would be diverted for irrigation, and the loss of water to the Dead Sea would be compensated for with sea water from the Mediterranean. The head would be exploited to produce electricity. Planning for water and electricity passed to various government agencies with the establishment of the State of Israel in 1948. In 1974 the idea began to be taken more seriously. The government's Eckstein committee concluded that a project based on a tunnel driven from the Mediterranean to the Dead Sea was feasible. In 1977 the Neeman committee studied possible routes and recom- mended the one leading from Qatif to Massada. In 1981 the government authorised the project in principle and set up the Mediterranean-Dead Sea Company, which delivered a detailed study on engineering, economic and environmental aspects of the whole hydroelectric scheme last year. <2Effect on the environment>2 A project of this scale obviously has wide environmental impact. This is being watched by the Environmental Protec- tion Service, a public body located within the Ministry of the Interior. A key issue is the effect on the Dead Sea, focused around two main elements--the water level and the salinity. The water level has undergone many changes in past history, due to natural and, more recently, to man-made factors. The proposal is to raise the level to what it was in the 1930s. The Dead Sea is a terminal lake into which drains the River Jordan and its tributaries, as well as the streams flowing from the Judean, Edom and Moab Mountains and the Arava. Once, the Jordan carried some 1.2 billion cu.m of water per year to the Dead Sea; other streams and ground water delivered an average of another 0.4 billion cu.m a year. Flows decreased dramatically in the 1960s with the completion of Israel's National Water Carrier, which conveys water from the River Jordan into the country's water grid, and after the Kingdom of Jordan diverted the Yarmuk. The Dead Sea has receded as a result. It covered some 1000 sq.km and stood at 393 metres below sea level in the 1930s. Now it is 800 sq.km and its level has dropped 9 m to 402 m below sea level. Evaporation lowers the Dead Sea some 1.6 m a year. Given this evaporation rate and the smaller inflows into the sea, the level is continuing to drop at a rate of about 0.5 m a year. In addition, the Jordanians are expected to complete the high dam at Maquarin this year. This will increase their exploitation of the Yarmuk waters via the Ghor canal. The River Jordan will then carry only some 200 million cu.m of water a year, a sixth of it's flow 30 years ago. The Dead Sea waters contain a high concentration of salts composed of potassium, bromine and magnesium as well as other minerals. The Israeli potash and bromine works at the southern end produce more than a million tonnes of these minerals a year. Hotels and resorts along the western shores exploit the climate and the sea's salts and sulphur springs. Raising the water level will re-submerge land along the shores which emerged after 1930. The potash works con- tinually has to raise its dikes, which hold water in evaporation pans, to prevent the pans becoming clogged with salts. The effect on salinity caused by bringing in less-saline Mediterranean water will be to return the sea to something approaching its former condition when the River Jordan inflow was strong. The lighter, sweet water of the Jordan used to float above the major body of heavy, saline water (specific gravity about 1.235 g/cc). There were few currents and mix- ing occurred very slowly. Mediterranean water (specific gravity about 1.04 g/cc) will now flow in and float, initially, above the heavy body of water. This separating into levels forms the basis for another large venture, the solar pond programme (see Box B), to turn solar energy into electricity. The hydroelectric scheme may involve the potash industry in an extra expense. The water being pumped from the Dead Sea by existing machinery could contain lower concentrations of min- erals, in which case water will have to be pumped from a greater depth (perhaps 70 m) where mineral concen- trations will remain high. Jordanian potash extraction will be affected in the same way as the Israelis'. One major issue on which a decision had to be taken was the route. Six alterna- tives were investigated (see diagrams). Two of them, the Hadera alignment and the Red Sea alignment, were eliminated at an early stage. Of the four remaining, the three mountain routes cut straight across from the Mediterranean coast and tunnelled through the Judean Hills. The final alignment began at Haifa Bay, passed overland through the Jezreel and Bet Shean Valleys, and followed the Jordan Rift Valley southwards until it reached the northern shore of the Dead Sea. The Environmental Protection Service pushed hard for the southern mountain route. Its case was based both on the opportunities that this route offered for regional development in the northern Negev, and on the destructive effects on the environment that any of the other routes entailed. The Haifa Bay route would have constituted a serious disruption as it passed overland through intensively developed urban and farming areas to the Jordan Valley, destroying property and agricultural land. There, another ques- tion arose: whether to use the River Jordan to carry the salt water, or to construct a chan- nel alongside it. The former option, turning the Jordan into a salt-water river, would have completely destroyed the existing ecosystem. The latter would have raised the cost considerably. The northern and central mountain routes also had serious problems. They would require extensive tunnelling through limestone under the Judean Hills where there was a danger of underground cav- erns or water. They would also pass close to the centre of the main sweet-water aquifer of the Jerusalem region. Israel is a country with a chronic water shortage. The possibility of salt water seeping into fresh-water tables carried heavy weight in the decision process. The southern mountain route, although also tunnelling through the Judean Hills, passes through limestone for a shorter distance and at the edge of the aquifer, where the water is already somewhat brackish. <2Financial benefits>2 The potential spin-offs of the southern mountain route for the Negev region are manifold. No other route offered such opportunities. The water can be used for industry, or breed- ing salt-water fish. It can also be used to cool thermal power stations, so far located on valuable coastal land near cooling water. Tourism can be developed around salt-water lakes. The hope is that the scheme will inspire new industrial and recreational areas near the canal. In the process, population and economic pressures could be relieved from the heavily developed central region. Economic and environmental arguments favour the south- ern mountain route from Qatif to Massada. Political prob- lems remain. The route has its intake in the Gaza Strip, which is occupied territory captured by Israel in the 1967 Arab-Israeli war. The recent UN conference on energy in Nairobi condemned the project as a whole, and the route alignment in particular, by a strong majority. The UN dispatched a three-man working committee in May 1982 to Israel and Jordan to investigate the principles and likely effects of the project. It consisted of a legal adviser, Stephano Burchi; a geologist, Tony Sutcliffe; and a civil en- gineer, Ter Mincassian. The committee's report did not strongly support either the UN's denouncement of the scheme, nor Israel's arguments for it. The members thought that it was technically feasible and, under the right condi- tions, could benefit the region. A modified version of the southern mountain route has been examined because of the resolution. This alignment has its intake at Zikim, between Ashkelon and the Gaza Strip. It is slightly longer and more expensive, but is nevertheless a viable alternative should the Qatif alignment be politically unfeasible. [] <2A: Israel's energy plans>2 ABOUT 99 per cent of the energy con- sumed in Israel is derived from im- ported oil. The Mediterranean-Dead Sea Project is part of the government's plan to diversify this narrow structure. No hydro- electric resources are being exploited in the country (the only electricity-generating dam was destroyed in the 1948 War of In- dependence). Solar energy accounts for 2.5 per cent of electricity generated, making Israel a leader in the use of solar energy. About 200 000 solar water heaters are used. Some natural gas is produced, but in amounts not significant to the national economy. The government decided in 1973 to promote nuclear power, but the idea has been held up by unresolved questions con- cerning the environment. Israel is small and densely populated so it is extremely difficult to find a site for a nuclear plant. Deposits of oil shales have been discov- ered at Ein Bokek near the Dead Sea. Their potential is under study. Peat deposits exist in the Hula Valley in northern Israel. It is suspected that the peat serves as a sediment filter in the watershed of Lake Kinneret. Its removal is not being contemplated, pend- ing further research. There is some promise of geothermal energy. Data obtained from oil exploration drillings in the Ashdod area indicate large amounts of hot brine at depths of 2450--3350 m. It is believed that similar reserves exist along the coast. The heat could be used by industry, as well as to heat homes and greenhouses. Wind driven generators are economical where wind velocities average 6 m/s or more. Several areas in Israel qualify, such as the Heremon Mountain slopes, the mountains of upper Galilee, the Negev Plateau and the Sodom area. Some esti- mates suggest that wind power could save 5-10 per cent of the fossil fuel used by the Electric Corporation. Israel consumes about 2140 kWh/year per capita, compared with a world average of 1285 kWh/year and an American average of 11 000 kWh/year. Electricity comes from three power stations on the coast which burn three per cent sulphur oil. The Haifa station gener- ates 492 MW, the Tel Aviv one 568 MW, and the Ashdod one 1021 MW. Gas tur- bines produce 335 MW. A power station, which can operate on coal or oil, is being built on the coast near Hadera. The plant, which will generate 1200 MW, will use imported coal. The Energy Ministry foresees Israel's electricity supply having to reach a figure of 10 000 MW by the year 2000. Present gen- erating capacity is about 2400 MW. If expectations are fulfilled, 30 per cent or more of this power could be produced, directly and indirectly, by the Mediterranean-Dead Sea Project. However, the intention is to use the hydroelectric power for two, possibly three, major schemes. The first, expected to produce 1500 MW, is the solar pond programme (se (Box B). The second is the proposed building of new thermal power stations (nuclear or coal or oil fired) in the Negev along the canal route, using the canal water for cooling. These stations should produce about 1000 MW. The third scheme is the exploitation of the oil shales near Ein Bokek, which will also require cooling water. [] <2B: Power from solar ponds>2 SOLAR-POND power generation relies on a simple phenom- enon. When the rays of the sun strike a shallow pool of still water (1) with a dark bottom the radiation is absorbed at the bottom (2) and heats up the lower levels of water. Ordinarily this heated water rises to mix with the cooler water and the heat rapidly dissipates to the atmosphere. However, in the solar pond the lower levels of water are more saline and heavier and therefore cannot rise. The lower levels get hotter and hotter and store energy which can be used to generate power. Temperatures of 80-90sC at a depth of 1-2 m are common. Hot water is converted to electricity, by a turbine (3) made in Israel by the Ormat Company. The turbine employs the difference in temperature between levels to produce vapour pressure in a working fluid, and so turn a simple generator (4). Solar ponds are being developed in Israel, where it is hoped that they will eventually contribute 1500 MW. This is dependent on the building of the Mediterranean-Dead Sea Project, for it is the lighter Mediterranean water that will constitute the upper water levels in the solar ponds. The idea is to create huge solar lakes on the Dead Sea. The first solar pond power station, with a rated capacity of 150 W, was inaugurated at Win Bokek on the shores of the Dead Sea in 1979. The 7000 sq. m pond, believed to be the largest operating solar collector in the world, was intended to provide hot water for a nearby hotel. Turbo-generators were added and it now also generates electricity. This station is soon to be followed by another 250 000 sq. m pond which will generate 5 MW. [] <2Microchips aid quantum physics>2 <2Technology from the semiconductor industry has allowed an experiment in fundamental physics>2 <2previously possible only in theory. This is the story of the quantum Hall effect>2 <2Colin Hurd>2 FUNDAMENTAL science often leads to fresh technologies and even to new industries, but is is far less usual for developments in technology to lead to new science. A good example of this "reverse flow" comes from certain developments in the semiconductor industry. These have al- lowed scientists to define a new absolute standard of electrical resistance, and to determine in a new way one of the most important physical con- stants. The one thing that these, and other applications have in common, is a mea- surement of the Hall effect, in which, in certain circum- stances, a voltage is set up perpendicular to a magnetic field and a current passing through a material. What the new technology has allowed is the study of the Hall effect at the level where quantum theory takes over from "classical" electromag- netism, in other words, the quantum Hall effect. The essential technology behind this breakthrough was the development of a type of transistor, the MOSFET, or metal-oxide- semiconductor field-effect transistor (Figure 1). This is a device consisting of a slice of insulator sandwiched between a piece of metal, known as the "gate", and a semiconductor. The semicon- ductor is usually a single crystal of p-type silicon, that is, silicon doped with excess positive-charge carriers, or holes. Electrodes to admit and extract current, known as the "source" and "drain" respectively, are embedded in the semi- conductor. A strong positive voltage applied to the gate draws excess mobile electrons (which are negatively charged) into a layer between the insulator and the semiconductor. The source and drain are thus connected by a so-called "inversion layer", in which the majority charge carrier (electrons) is the minority one in the bulk of the semiconductor (which is p-type, so holes are the majority carrier). Using a voltage to control the number of mobile electrons in this layer, or "in- duced surface channel" as it is sometimes called, is the basis of the device's operation. Interest in the scientific potential of the inversion layer was awakened in the late 1950s. Theoretical considerations indi- cated that if the electric field applied to the surface could be made strong enough to confine the mobile electrons to a very thin layer near the semiconductor's surface, with thickness comparable to the wavelength associated with the electrons there, then the electrons' motion perpendicular to the surface would be "quantised". In other words, only certain discrete energies would be permitted, exactly as for an electron con- fined in a single atom. Motion parallel to the surface, on the other hand, would remain as normal. About 10 years passed before the technology could produce satisfactory inversion layers thin enough to show quantum effects, that as, less than about 10 nanometres thick. An im- portant step was to show that if the semiconductor is cooled sufficiently for all the electrons to be in the lowest permitted energy states, then the mobile electrons in the inversion layer can move only in two dimensions. Normal motion is possible parallel to the semiconductor's surface but movement per- pendicular to the surface is forbidden. The permitted energy states in such a system forrn a so-called "surface sub-band", and when all the mobile elec- trons are contained in one sub-band we have reached the <1electric quantum limit.>1 The two-dimensional be- haviour of electrons in the MOSFET structure was ex- citing news to experi- mentalists because they could test some of the un- usual and potentially useful properties that theory pre- dicted. Much research along these lines is going on in var- ious parts of the world; the quantum Hall effect is an off- shoot that derives from curi- osity about the effects of a strong magnetic field applied perpendicular to the plane of the two-dimensional system. The Hall effect is normally measured in a thin, rectan- gular plate (Figure 2). When an electric current passes lon- gitudinally through the plate in a magnetic field, the so- called Hall voltage appears across the direction perpendicular to both the current and the field <1(New Scientist,>1 vol 84, p 536). Suppose that the plate is the inversion layer in a MOSFET. Current then flows between source and drain in a surface channel maintained by the gate voltage, which con- trols the concentration of mobile electrons. For electrons moving freely in the layer, albeit in two dimensions only, classical theory says that the Hall voltage should depend in- versely on the density of mobile electrons: more electrons means a lower voltage. The Hall voltage should therefore decrease smoothly as the gate voltage (V) is increased, as this controls the density of electrons in the inversion layer. But quantum effects can appear, as Th. Englert and Klaus von Klitzing at the University of Wu%rzburg discovered about five years ago. They found that the Hall voltage in silicon MOSFETs does not vary smoothly but makes quantum steps as <1V>1 is varied in a fixed magnetic field. The uniform decrease of the Hall voltage with increasing electron density is inter- rupted by plateaux where the voltage is constant (Figure 2). Furthermore, these plateaux coincide with deep minima in the longitudinal voltage, in the direction of current flow, which drops essentially to zero at the critical values of <1Vg.>1 Most surprisingly, as von Klitzing and his colleagues showed only a couple of years ago, the Hall resistance at each plateau, measured as the ratio of the Hall voltage to the longitudinal current, appears to be precisely a multiple of fundamental constants, <1h/Nes,>1 and is completely independent of all experi- mental parameters. (Here <1h>1 is Planck's constant, <1e>1 is the electronic charge and <1N>1 is some multiple 1, 2, 3, . . .) Two potential uses appear immediately. First, as <1h/ez>1 has the dimensions of the ohm, the unit of resistance, we can use a MOSFET as a resistance standard. The ratio is equivalent to about 25.8 kilohms. This new standard would depend exclu- sively on fundamental constants and, unlike existing counter- parts, would not be handicapped by troublesome corrections necessary to account for imperfect experimental conditions. Secondly, the ratio <1h/ez>1 fixes the fine structure constant, a, which otherwise depends only on the speed of light. This constant is important because it fixes the sizes, period and energy of an electron's orbit in an atom. The new mea- surement of a would be independent of previous techniques and potentially more accurate <1(New Scientist,>1 vol 93, p 572). With an uncertainty expected to be less than 10-7 in a value of about 137.035 it should be possible to test directly quan- tum electrodynamics, or QED, the quantum theory of elec- tromagnetism. So all that remains, apparently, is to develop the technology to the desired level of convenience to exploit these new experiments; various groups around the world, notably at Bell Telephone Laboratories and the National Bureau of Standards in the US, are well advanced in experi- ments of this kind. <2Now for the puzzles>2 This might seem like the end of a successful story, but far from it! Understanding the quantisation experiments has not been easy and is still controversial. There are essentially two puzzles. First, the existence of the plateaux over appreciable ranges of <1Vg>1 (Figure 2) does not match preconceived ideas for quantised motion. Secondly, although the integral values of the Hall resistivity at the plateaux can be explained by a simple theory that glosses over many of the complications of real inversion layers, nobody expects such outstandingly good agreement, better than 1 part per million, with a theory so coarse. Faced with these results, many theorists think that Nature is trying to tell us something fundamental. To explain this reaction, I must first introduce some concepts that help the physicist to describe what is happening in an inversion layer. The microscopic behaviour of the mobile electrons is best described in terms of "<1k>1-space", which is an idea borrowed from crystallography (Figure 3). Each mobile electron in the system is represented by a point in <1k>1 space such that the vector from the origin to the point is proportional to the electron's momentum, and so represents both the magnitude and direction of the momentum. So if electrons can move freely in three dimensions, at the absolute zero of tem- perature the occupied states in <1k>1-space form a sphere (dashed in the Figure). This contains points representing all occupied states from zero momentum at the centre of the sphere up to some maximum value equivalent to the radius and corre- spending to the co-called "Fermi energy". The sphere is the configuration with minimum energy consistent with a fundamental "exclusion principle" that states that each mo- mentum state may contain at most two electrons. Points at the Fermi energy are the only ones adjacent to vacant, higher energy states and so represent mobile electrons that can be accelerated, by an electric field, for example. Reducing the thickness of the inversion layer to about the wavelength of an electron quantises the motion as the dia- gram shows: the permitted states lie on infinitely-thin discs in <1k>1--space, each corresponding to a surface sub-band. The en- ergy separation of the discs increases with decreasing thick- ness of the layer. Electrons may have enough thermal energy to jump between states in adjacent discs at ambient tem- perature, but this can be practically impossible at very low temperatures (where the electrons do not have much energy) in a very thin layer (where the separation is large). All occupied states are then represented in a single disc (dotted in the Figure), corresponding to the "electric quantum limit". When a magnetic field is applied, each mobile electron is forced to spiral about the field's direction, although its energy is not changed. This additional angular motion imposed by the field is quantised, exactly as if the electron was con- strained in an orbit around an atom. With the field applied normal to the inversion layer, we thus have two quantisations to contend with: "spatial" (due to the thinness of the in- version layer) along the field's direction. The spatial quan- tisation scheme in <1k>1-space then breaks up into a series of concentric circles about the field's direction (Figure 3). The total number of representative points in the system is un- changed, so these circles consist of closely-spaces points that have "condensed" from forbidden parts of <1k>1-space onto the nearest circle as the strength of the magnetic field increases. The condensation of points from forbidden parts of <1k>1- space leads ideally to perfectly sharp energy states, known as Landau levels (see Box) with no allowed states between them. There should then be no plateaux in the Hall voltage because as more electrons are added to an unfilled Landau level we expect a smooth decrease of the Hall voltage. When one Landau level is full, the addition of just one more electron puts the Fermi energy <1EF,>1 at the bottom of the next level, and the decrease of the Hall voltage should continue with imper- ceptible disturbance. Since plateaux do appear, as Figure 2 shows there must be some mechanism working to prevent this smooth movement of E<1F>1 from one Landau level to the next. Furthermore because the Hall voltage is independent of the gate voltage V<1g>1, on a plateau, there must also be some form of electron reservoir able to keep the electron density constant, for, remember, the Hall voltage should depend on the density of mobile electrons. But one we assume in the derivation of the precise result for <1h/Nes,>1 with which experi- ment agrees very well. [] <2A very exceptional result>2 Figure 2 contains the clue to this quandry: the plateaux in the Hall voltage coincide with ranges where the longitudinal voltage is essentially zero. In other words, although a longi- tudinal current is flowing, it is without resistance. This is a very exceptional result. Resistance comes from mobile elec- trons losing momentum in scattering and is usually inevitable except in superconductivity. But here electrons are somehow flowing the length of the channel without being scattered to any measureable extent, yet the scattering can be switched on again simply by varying the gate voltage, <1Vg>1, enough to bring the Hall voltage off a plateau. All this occurs in magnetic fields very much above the maximum tolerated by the super- conducting state. To understand this behaviour we must consider the mag- netic quantisation in terms of the Landau levels. In a real inversion layer the Fermi energy lies in a gap between when a whole number of levels are filled with electrons (see Box). This "mobility gap" separates the occupied "delocalised" states that contain the mobile electrons (and are so-called precisely because they can move around in the semicon- ductor) from vacant delocalised states in higher Landau levels. At low enough temperatures the gap is insur- mountable, and dissipative scattering (with loss of momen- tum) is impossible because there are no vacant delocalised states that an electron has sufficient energy to reach. On the other hand, occupied <1localised>1 states, confined to limited regions of the semiconductor, do exist adjacent to vacant localised states, at energies just below <1EF,>1 and their electrons can move by thermally-activated "hopping between sites. But the probability for this to occur decreases very rapidly with decreasing temperature. So at low enough temperatures, with the gate voltage, <1Vg>1, chosen to put <1EF>1 in a mobility gap, all the current is in effect carried by electrons that cannot be dissipatively scattered, and the resistance falls <1to zero. Of course, if V>1 is varied to put <1EF>1 into the range of <1delocalised>1 states in a Landau level, vacant states are then adjacent and dissipative scattering is again possible. The longtitudinal voltage then regains its normal non-zero value (Figure 1). All theoretical treatments of the quantised Hall effect pro- posed so far require there to be no dissipative scattering if they are to account for the values of <1h/Nes>1 at the plateaux. The practical accuracy of this result, which is central to the deter- mination of the fine structure, constant, is believed to be limited only by the residual dissipative current due to hop- ping through localised states. In choosing MOSFETs for such experiments, the aim is to keep this current as small as pos- sible, by minimising the density of electron traps at the inter- face between the semiconductor and insulator. MOSFETs fabricated on a particular face of the silicon crystal structure (the so-called (100) face) are the best. Lack of scattering does not, however, explain the existence of plateaux extending over a range of values of the gate volt- age. But they too are a consequence of the localised states, which enable the system to tolerate a range of V over which <1EF>1 is separated from delocalised states. The mobility gap thus interrupts the smooth movement of <1EF>1 through delocalised states as Vg is altered. For example, as Vg is increased and <1EF>1 moves through a mobility gap, the extra electrons drawn into the inversion layer populate localised states, and the effective density of mobile electrons stay fixed. Hence the Hall voltage is fixed. The localised states thus act as an electron reservoir, keeping the effective density of mobile electrons constant over ranges of V that have widths proportional to the num- ber of states in the mobility gap. And, therefore, we observe the plateaux in the Hall voltage. But if the electrons in the inversion layer are connected to a reservoir, as we have asserted to explain the plateaux, one would not expect them to behave like free, independent par- ticles. Yet the Hall resistance at the plateaux has exactly the values expected from free-electron theory (see Box). The reason is believed to be a property that was known previously for a two-dimensional system: if small regions are rendered nonconducting then, providing there is a path connecting conducting parts, the Hall resistance is scarcely affected. Extra current is carried by the conducting parts to offset the lack in the nonconducting ones, and the Hall resistance remains constant. The localised states form the nonconducting regions in the electric quantum limit. If we could see the lines of current flow for the rectangular inversion layer we have considered, on a microscopic scale they would look something like the sketch in Figure 4. When the Fermi energy, <1EF,>1 is in a mobility gap, the regions of localised states act like current vortices: they store electrostatic energy as reservoirs of circu- lating electrons that are depleted or replenished as <1EF>1 is moved by the gate voltage, Vg, but they do not add to the conductivity. The current then comprises mobile electrons that cannot be dissipatively scattered, and which of course have exactly balanced transverse forces to give longitudinal motion without sideways deflection. The current skirts the nonconducting regions, just as a superconductive current avoids normal regions, but the Hall voltage is independent of Vg. When <1EF>1 lies in a Landau level (Figure 4), scattering is possible and the current flow comprises electrons with paths that are constantly modified at each collision. The internal picture would then look exactly like that for the Hall effect in any normal conducting solid, except that it is limited to two dimensions. By no means has the last word been written on the quan- tum Hall effect. Theorists are tempted by the analogy between the lossless current and superconductivity and by the chance to test QED. There are presently two ways to measure the fine structure constant, a, only one of which depends on the correctness of QED. The quantum Hall effect provides a third independent method, so in principle comparison of three sets of results could check QED. Experimentalists, on the other hand, are excited by the demonstraton of electron motion under previously hypothetical conditions, and are looking to other devices where the same effects can appear in less stringent experimental circumstances. The application of the strange properties of the quantum Hall effect is still in its infancy but the rewards of this reverse flow from technology to pure science could be very great indeed. [] <2Landau levels, mobility gaps and the quantum Hall effect>2 ANOTHER way of looking at the magnetic quantisation of Figure 3 is shown in the energy band dia- gram (a). In a strong magnetic field the allowed enengy states form a fairly evenly-spaced succession 0, 1, 2, . . . of so- called <1Landau levels.>1 These contain the same number of electrons as the band of allowed states that exists when there is no magnetic field. (I shall through- out neglect complications due to the spin of the electron and peculiarities of the particu- lar semiconductor's band structure.) Ideally, the Landau levels are discrete and perfectly quantised. If the density of points in k- space is written N(e) , then its variation with energy in a strong magnetic field is a series of infinitely-thin spikes (b). And if B is the magnetic flux, each Landau level contains <1B/H>1 energy states. The first attempts to understand the quantised Hall effect were in terms of this ideal model. It is a standard result that the Hall resistance in a strong field is <1B/ne,>1 where n is the two-dimensional density of mobile electrons, assumed to be free, inde- pendent particles. Suppose the electrons just fill exactly an integral number N of Landau levels. Then <1n=NeB/h>1 and the Hall resistance is just <1h/Ne2,>1 in agreement with experiment. Furthermore, when a whole number of Landau levels are completely filled there are no accesible vacant states and the electrons' kinetic energises cannot be increased (the electrons cannot be accel- erated), unless electrons can jump to vacant states in a higher Landau lever, but this is impossible in the electric quantum limit. The drop to zero of the longitudinal voltage (Figure 2) reflects this inability of electrons to be accelerated by an electric field, thus, researchers argued, because the number of mobile electrons in the MOSFET is changed by the gate voltage sweeping the Ferm energy, <1EF,>1 through the Landau levels, the experimental features of Figure 2 reflect the critical circumstances as successive Landau levels are completely filled. But this simple explanation conceals flaws, as the main article points out. Moreover, in a real MOSFET the Landau levels are not sharp spikes but are broadened in energy and have overlapping "tails (c). This broadening is due to collisions between electrons, between electrons and imperfections or the walls of the sample, or by the randomness on an atomic scale of the electric potential the electrons feel. Because the interface between semi- conductor and insulator is never entirely smooth, there is a "disordered" component in the potential. Its effect is that states in the tails of the distribution <1N(e)>1 become traps that confine electrons to limited regions of the semiconductor. A sharp energy, called the mobility edge, separates these "localised" states from the "delocalised" or "current-carrying" ones, which contain electrons that can range throughout the semi-conductor. The energy span between mobility edges of adjacent Landau levels (shaded in c) is called the <1mobility gap.>1 When a whole number of Landau levels are filled in a MOSFET, the Fermi energy, <1EF>1, lies in a mobility gap. Then the regions of localised stated behave like vortices of cir- culating electrons, around which the mobile electrons flow. [] <2REVIEW>2 <2Doubts and convictions about Charles>2 <2Evolution without evidence>2 by Barry Gale, <1Harvester,>1 pp 238, #18.95 <2The descent of Darwin>2 by Brian Leith, <1Collins,>1 pp 192, #7. 95 <2Arthur Cain>2 IT WOULD be interesting to have a league table for literary industries--has the Darwin industry now surpassed the Wittgenstein industry? Is the creationist industry second or first division? And so on. These are, I hope, the last Darwin books I shall have to read for some years (unless of course Sydney Smith produces one). With the end of the centenary year, one hopes the flood may reduce to a trickle, About all that the present two books have in common are their catchpenny titles. <1The Descent of>1 <1Darwin>1 is about the present controversies, real, exaggerated, or downright lunatic fringe, it matters not what, over neo- Darwinism. <1Evolution Without>1 <1Evidence>1 is not a creationist broadside, but an interesting and well-written exercise on the theme that the young Charles Darwin became convinced of evolution but felt that he did not have the evidence to convince his contemporaries, and spent a long time getting it together and arranging it--so long that he was taken by surprise and had to get out the <1Origin>1 prematurely (as he always said himself). The author of <1Evolution With->1 <1out Evidence,>1 Bay G. Gale, took his PhD in the history of evolutionary thought, at the University of Chicago, and has been a fellow of the National Sci- ence Foundation and member of Darwin College, Cambridge. At present he is stated to be "a senior government official in the research and development area of the Department of Energy in Washington DC" (from book- jacket). The book is almost predictable from this informa- tion. As already said, it is well written, and carefully documen- ted with extensive notes. Warning--the reference to the <1Life and Letters of Charles Dar->1 <1win>1 are to some two-volume American edition, not to the original English one (which is surely accessible enough?). Dr Gale has read carefully his primary sources and a surprising number of the secondary ones, and his thesis is well made out. He takes us through Charles Darwin's earlier years, the development of his ideas, his recorded (and suspected but probable) ambitions, shyness, doubts, agonies, successes and rebuffs with real insight as to Charles's personal relations with Charles Lyell and Joseph Hooker. In particular (and his present position seems to indicate Gale's earlier predilections and his fit- ness for the task), he examines Charles's worldwide correspon- dence, his ability to charm others into working for him, his capacity for synthesising from others' data and conclusions. It is, perhaps, not very different from what anyone has to do to- day who is interested in the higher generalities of evolution, except of course that there is less need to get people to do specific jobs, because there are so many people publishing anyway. Nevertheless, Charles's activities have not to my knowledge been examined, certainly not with such thoroughness, from this angle before. And this is a useful contribution I cannot believe that the book jacket blurb was seen by Barry Gale; it informs us that "In 1859, when Charles Darwin published <1The Origin of Species,>1 he had no more evidence in sup- port of his theory than did the creationists . . ." which is a carri- cature of Gale's quite un- exceptionable thesis. It equally informs us that as one of the re- sults of his "innovative" study "Gale also shows us a Darwin who relied on the help of other scholars for much of his work on species . ." Good God, what a revelation to us all! Authors should have the power of veto over blurbs--the book deserved a better one than this. Where the book is less than satisfactory is equally predict- able. Modern American scholarship in the history (and philosophy) of science is very addicted to setting up straw men (sometimes they are even called myths, with unconscious truth) and demolishing them. Gale justifies his efforts in part by stat- ing "The idea that Darwin returned from Beagle voyage a finished naturalist ready to take the British natural history community by storm is simply not true . . .". Gale himself quotes John Henslow's own estimate (to Charles himself) of Charles's abilities. Apparently from the notes, a certain Frucht- baum in the <1Times Literary>1 <1Supplement>1 has described Char- les on setting out on the Beagle voyage in such terms, which is certainly an exaggeration, but I do not know anyone else who has ever subscribed to that opin- ion. A recent (excellent) paper by Frank Sulloway in the Gala- pagos symposium at the Lin- nean society in December was also in part devoted to demolish- ing myths which I had never heard of. But what is more important is that Gale's book loses much of its impact because the science is not there to anything like the ex- tent it needs to be to make the difficulties of Charles's position clear. So much American work in the history (and philosophy) of science is a very scholarly playing-about with ideas, but omits what those ideas are actu- ally based on. So here, and it comes out even in the misprints. Charles did not get into difficulties over "the south American quadruped"--it was a whole fauna of them. And it was not a "crest" but cress that was involved in his experiments on seed flotation germination. This is symptomatic of much more important weaknesses-- Charles did not as Gale states "hypothesise a glacial period in the distant past" as a stop gap for ignorance -- James Smith of Jordanhill and others had already shown that there was good evidence for a cold period on actual fossils. Louis Agassiz had shown from geological evidence that glaciers (not just icebergs as Smith thought) had existed in the British Isles. Edward Forbes, indeed, had an- ticipated Charles with his theory of the disjunct distribution of arctic-alpines. Gale underrates what Charles did scientifically; he also underrates the opposition -- he gives no refer- ences, for example, to who held the theory of multiple creation, nor to why. The creationist posi- Lon in the <1Origin>1 is never merely a straw man to be knocked down. But equally, Gale gives no indication that he himself has understood how obviously ridic- ulous Lamarck's theories of physics and chemistry were in his own day -- and it was on these that his theory of evolution was based. Nevertheless, Barry Gale's book is well worth reading, and a useful contribution to the litera- ture on Darwin. Brian Leith's <1The Descent of Darwin: A Hand->1 <1book of Doubts About Darwin>1 can hardly be recommended in the same terms. Leith is at present a producer in the BBC (Bristol). This book seems to be based on the techniques I have long suspected some producers use to keep a discussion going for the full length of a pro- gramme whether there is any- thing in it or not, to keep up the emotional temperature even about unexciting things, and to emit statements which are just distorted enough to get people objecting, whether they are worth objecting to or not. Leith's prose is as emotionally loaded as he can make it -- Darwin himself "confessed" that imagining the eye to have evolved was almost absurd (Leith of course makes no mention of Darwin's reference to the sequence of eyes from very imperfect to almost human in invertebrates). To "the staunch neo-Darwinists" genetic drift is "virtually" a dirty word (quite untrue-- I don't know one that doesn't accept that it will occur given the circum- stances). Rupert Sheldrake is "now infamous". Neo- Darwinism was so formidable (but why?) that "virtually no respectable academic" . . . "dared" contradict it. science is "notoriously "blinkered'" (and what do his inverted commas mean?). The "established" gen- etic thinking and the "established" neo-Darwinian thinking have been "unnecessarily narrow-minded and complacent" (how much would be necessary?) -- and so on and on. Conversely, he lauds any ideas, however shaky, that will promote controversy as "interesting and entertaining" (the inevitable spandrels) and "really very exciting". He gives a completely uncritical account of cladistics on the valuation of its own practitioners; it is "objective and powerful", an "advance in taxonomy because of its rigour"; Willi Hennig's principles are "simple and sensible", and so on. This is totally one-sided. The only rigour in Hennigian cladistics is produced by the straitjacket of assumptions that Hennig has fastened on himself and his ver- sion of the subject, which effec- tively separates it from having anything to do with evolution. Leith's history of biology is not too good - there were not fashionable Lamarckian <1revivals>1 before Charles Darwin put pen to paper, the time gap was too small. And acquired characters is not the essence of Lamarckism but a belief that Lamarck shared with all his contemporaries. Some of his biology is not too sound; his statement that the gulls of the northern hemisphere may be exceptional -- "In the majority of species such gradual variation is not seen, and all the members are equally interfertile" -- seems based on a plentiful lack of knowledge of the work that has been done on geographical variation in many groups of animals, including birds. Moreover, in presenting evi- dence contradicting established views (if it does) Leith often gives no references (for example, on the superior viability of eggs of melanic moths) and it is impos- sible to check his assertions. Al- most nowhere does he present an argument in a straight- forward way. We have Karl Pop- per's criticisms of evolutionary studies; but it is another two pages before we get his re- cantation, prefixed by the words "to be fair to Popper". Again, in discussing punctuated equilibria (much or the initial impact of which depended on the assertion that Darwin had got things wrong) it is not until after several pages that we are told "It is at this stage entertaining to realise" that Darwin "anticipated the present debate". Why not be fair to the reader as well as to Popper? Much of Leith's discussions are difficult to follow because he never makes clear, in dealing with doubts about neo- Darwinism, what are really un- warrantable, what are due to muddle, what arise only from practical difficulties in actual re- search, and what are real doubts of principle. He quotes Occam's razor but never dreams of ap- plying it to most of the contro- versies he refers to, and, iron- ically over macroevolution, thinks that some of the recent speculations "must inhibit the penchant for 'story-telling' and the glib explanation", of the neo- Darwinists. If the penchant for story-telling and the glib expla- nation could be inhibited in most of the attackers of neo- Darwinism (the uninhibited producers of Not So Stories), there would be less noise and more sense in the world, and his book not written. It would take the length of a book to provide an adequate commentary on Brian Leith's book, but fortunately it is hardly required. For a careful and sober assessment of most of these con- troversies and a fair statement of both sides there is already Michael Ruse's <1Darwinism>1 <1Defended.>1 []  <2Is it safe to breathe?>2 <2Lead on the brain>2 by Nick Kollerstrom, <1Wildwood, pp 117, #2.95>1 <2Mick Duggan>2 NICK KOLLERSTROM's book claims to be "a plain guide to lead pollution". There is some need for such a guide, but unfortunately <1Lead on the Brain>1 does not fill it. The fundamental issue in the current debate is whether environmental lead causes intellectual impairment or be- havioural disturbances in children. The great majority of studies have found small but sig- nificant differences in intel- ligence and behaviour between children with high and children with low levels of lead in the body. But the existence of a causal relationship is still de- bated. Again, it has been demon- strated that even quite low levels of lead interfere with body pro- cesses. A study of "healthy" schoolchildren (to use Nick Kollerstrom's examples) found significant differences between the electroencephalograms (elec- trical recordings of brain activity) of children with a high content of lead in the body and those with a low content. But what can still be debated is whether such phenomena are re- lated to the neuropsychological damage often attributed to lead. Kollerstrom does not seem to realise that the debate has now reached this stage. He too glibly assumes that correlation proves causality and he does not show--as he could have done--that the balance of evi- dence does indeed suggest a causal association. Moreover, on occasions he is misleading in his presentation and discussion. For example, the uninformed reader will almost certainly conclude that Herbert Needleman's neu- ropsychological tests were car- ried out on not just 158 children but on all 2000 children in the study. And Kollerstrom is quite mistaken in supposing that this part of the study could show whether or not there exists a threshold below which no effects occur. Worse still, he implies that both the Needleman study and the more recent one by Bill Yule and Richard Lansdown provide evidence that a child's lead content has more influences on intelligence and behaviour than do social and other factors. Kollerstrom also misleads by explicit error. For example, the "EEC recommended air lead limit..." is not 1.5 but 2 micrograms/cu.m, and the suggestion that the air in British cities is "statutorily unfit to breath" is incorrect. He tells us that a concentration of lead in water of 50 g/litre may be re- garded as an "upper safe limit" and yet later on mentions with approval a suggested limit (for children) of 0.1 ug/g for lead in food. In fact, for a two year old, the former (water) limit would give a daily lead intake of about 25 mg, compared with about 10 mg from the latter (diet) limit. Elsewhere, Kollerstrom appears to assume that a concentration of lead in the diet of x mg/g will produce a concen- tration of x mg/g in blood--this is an astonishing error from a scientist concerned with lead toxicity. The catalogue of such errors is perhaps the most serious charge against this book. But in addi- tion, the presentation--far from being "simple and rigorously sci- entific" as the back cover suggests--is at best inelegant and meandering, and at worst con- fusing and journalistic. The case against environ- mental lead is very strong, but an argument that contains such exaggeration and error can only be a weak one. Nick Ko- llerstrom's book will not help in the campaign to recognise and reduce the hazard from lead in our environment. [] <2Conversation with Freud's patients>2 <2The Wolf-Man: 60 years later>2 by Karin Obholzer, <1Routledge, pp 250, #12.50>1 <2Colin Brewer>2 THIS is a fascinating book. It is also, for the many people who feel, as I do, that Sigmund Freud's influence on psychiatry has been generally damaging, a rich source of <1Schadenfreude.>1 The Freud who emerges from these recollections of one of his prize patients is evidently quite sincere, "liberal" in a Hampstead-ish way, thoroughly well-intentioned, but dogmatic, arrogant and autocratic. Too arrogant indeed, to know when he had failed. One could almost summarise the book in a paraphrase. You cannot hope to bribe or twist, Thank God! the Viennese analyst. But seeing what the man will do Unbribed, there's no occasion to. While we are on the subject of money, it is interesting to note that Freud's fee for an hour of his time was nearly four times the fee for a day in "a first rate sana- torium". The Wolf-Man--so called because of a dream involving wolves which Freud interpreted as a memory of his parents having sex--saw Freud for an hour a day, every day except Sundays, for four years. When it seemed that the treat- ment was over, Freud suggested the patient should give him a present "so that the feeling of gratitude wouldn't become too strong". Judged by these remi- niscences, recorded over a five- year period in the mid-1970s by a respected Austrian journalist, Freud's anxieties on that score were somewhat excessive, to put it mildy. The Wolf-Man--a rich Rus- sian identified in a tantilisingly Chekhovian fashion only as "Segei P-"--was certainly a bit odd. Though, as he himself realised, with a hypochondriacal mother, a sister who committed suicide, an uncle who lived "like King Ludwig II of Bavaria" and a paranoid cousin who died in an asylum, perhaps that was not surprising. He was, and clearly remained to the last days of his long life, a fairly severe obses- sional-rigid, indecisive, racked with doubts and unable to rid himself of a penchant for rather down-market women which led him into a series of miserable relationships. When Karin Obholzer inter- viewed him, he had been locked into one of these for over 10 years. His inability to rid himself of the woman is a recurrent theme, even though a psycho- analytic institute in the US (where for some reason another analyst has written a book which presents the patient as a great therapeutic success) actually sent him money regularly so that he could pay her off when she got too demanding. After Freud had done his worst it turned out that there was still an "unanalysed residue" when he had a major relapse some years later. He became convinced that his nose was de- formed and saw another analyst regularly for a few months, but he recovered--at least until the next lot of symptoms after he rejected her advice and inter- pretations and simply told him- self to stop thinking about his nose so much. To the end of his days, the poor man was addicted to psychoanalysis--agreeing that it sapped his independence and self respect but unable to kick the habit. Every year, he had a few sessions with a visiting American analyst and there were occasional visits to a local one. The advice was often con- tradictory. One feels constantly sorry for this randy but unsatisfied old man (Cynthia Payne's Strea- tham <1me/nage>1 was made for peo- ple like him) who had taken sleeping tablets every night for decades and toyed frequently with suicide. (Ms Obholzer blocked that exit by telling him that domestic gas in Vienna was now non-lethal.) He could also be, as she concedes, tedious and repetitive. Yet he gives us an authentic account of his epoch and of its medical habits. The very rich may still have their own exclusive personal physi- cians, but how many retain in additions, as he did, a medical student for the specific purpose of administering enemas? (The work done, the student would sometimes join the other two for a merry game of cards.) And, in- cidentally, how many analysts these days have a talking dog, as one of Freud's colleagues appar- ently had? Freud told the old Man that had he not become an analyst, he would have been an economist, which conjures up all sorts of hilarious posibilities. The Wolf-Man thought he wouldn't have got far in that dis- mal profession, though success in economics, as in psycho- analysis, can be difficult to define. But if the Wolf-Man is one of Freud's successes, it would be interesting if harrowing to read about one of his failures. [] <2Greenhouse effect>2 ----------------- Carbon dioxide review: 1982 edited by William Mark <1Oxford>1 <1UP, pp 469, #22.50>1 John Gribbin THIS large--format (22 x 28 cm) book provides the most information about the car- bon dioxide problem available in one manageable volume. It is a multi-author work, organised by the Institute for Energy Analysis of Oak Ridge Univer- sities, and is intended to be part of the broad COs programme in the US that has already pro- duced several official reports on different aspects of the problem, and will lead to a comprehensive report in 1985. But, as the editor says in a preface, the present vol- ume, free from the need to pro- vide an official, authoritative consensus, is better able to pro- vide "a forum for critical ap- praisal of current thinking". In view of that stated aim, I was surprised to find no mention of Sherwood Idso's claims that all of the fuss is a result of climatologists barking up the wrong tree, misled by computer models which are all making the same mistake. Whether or not you accept Idso's claims, surely this is just the place for a critical appraisal of them? I cannot be absolutely sure that there is no mention of Idso in the book because of its other glaring omission--there is no index. That said, no scientist, politician, or policy maker who has any interest in the future of mankind can afford to be with- out this book. I particularly like the presentation of key "essays" on specific topics, followed by commentaries from other experts which highlight the problems and put the essays in perspective. There is a real feel here for a developing area of research, which avoids giving a misleading impression that the current state of the art provides any ultimate answers, handed down on tablets of stone from above. The contributors succeed, by and large, in avoid- ing technical obfuscation, and anyone who reads <1New Scientist>1 should have no difficulty in absorbing the information here. This is an impressive and wel- come volume. [] <2Proof of an ancient civilisation>2 ------------------------------------- Qaryat al-Fau A. R. al-Ansary. <1Croom Helm, pp 147, #14.95>1 Lucia Nixon THE LOCAL environment of the Arabian peninsula makes large-scale agricultural exploitation difficult, so the in- habitants have always had to capitalise on foreign demand for available resources. When Bilqis, Queen of Sheba, travelled from her domain in southern Arabia to visit King Solomon, it was not just to pay a social call. She wanted to arrange sole rights for the overland trade in frank- incense and other goods between her country and the rich markets to the north. The biblical story is thought to reflect the then recent development of caravan routes, made possible by the domes- tication of the camel at the end of the first millennium BC. The incense trade continued to be important for the next 1500 years. As caravan routes became more organised, large cities sprang up it crucial junc- tions. One of these was Qaryat al-Fau in Saudi Arabia, located on the route connecting the south-west comer of the pen- insula with Syria and the Ara- bian Gulf. Six years of exca- vation at Qaryat al-Fau, directed by A. R. al-Ansary and spon- sored by the University of Riyadh, have yielded detailed evidence for a large settlement covering 2 sq.km, inhabited from the second century BC through to the fifth century AD. The buildings include a stone temple; a "palace" of two halls, with wall-paintings; and the souk or marketplace, which had two storeys of shops and store- rooms, surrounded by a heavy wall. Investigations in the resi- dential area uncovered houses and caravanserais with rooms for travellers set round large courtyards. Nearby was an agri- cultural zone with circular plant- ing beds for date palms and pos- sibly incense trees. Reservoirs, wells and canals demonstrate the ability to regulate water supply. Evidence from tombs suggests a stratified society with three so- cial classes. The small finds-- pottery, textiles, glass, stone, bone and metal tools, plus coins and weights--reveal a soph- isticated mixture of local Ara- bian tradition and the inter- national style of the Graeco-Roman Levant. <1Qaryal al-Fau>1 consists almost entirely of superb photographs of the site and objects found, with a brief commentary in En- glish and Arabic, meant to serve as an introduction for the 10 spe- cialist volumes to follow. The preface makes it clear that interest in the past in Saudi Arabia--as in all countries--is directly linked with present pros- perity. How appropriate, then, that a modern commercial na- tion should discover the remains of an ancient trading centre, such as Qaryat al-Fau [] <2Preservation and sub-atomic particles>2 ------------------------------------- EVER since I saw David Bellamy disappearing down a crack in a garden path to dem- onstrate that we all had our own "personal <1schooool>1 of evo- lution" close at hand, I have been prepared to concede him an eternal place among the inexorably tenacious. Then, he was presenting <1Bellamy's Backyard Safari>1 on behalf of BBC 1 and had been specially miniaturised for the role. When I heard recently on the radio that he had been ar- rested in Tasmania the wild fancy occurred that someone had forgotten to de-miniaturise him and that he had finally worked his way through to Aus- tralia. It would, one imagines, be entirely in character. But, as we all know, Bellamy was in Tasmania to aid the Tas- manian Wilderness society in its battle against the damming of the Gordon River, which the society holds to be in con- travention of the area's classi- fication as a world heritage site. He was, of course, released, not at all diminished on this oc- casion but as ever, larger than life Nature (BBC2, 27 January), in the third of its 10 programmes and already looking well- established and aware of its duty as a news programme, inter- cepted him at 2 am at Bahrein on his flight home. Dr Bellamy gave a spirited call for the preservation of an area he considers to be one of the top 10 botanical sites in the world and told how he had sat in the rain- forest imagining he was a dinosaur. Enough of him had, however, remained in the present to en- able him to present a powerful case for the area's preservation and to prophesy that the objec- tors would win. Tony Soper was <1Nature's>1 early-riser and this programme suggested it is something of a habit with him, for we also saw him in the Falklands carrying out an investigation into whether the war--or was it just a conflict?--had upset the wildlife there. He found it hadn't. The com- manding officer, General David Thorne said that was his im- pression too, as the wildlife-- which he had swotted up on before taking over--tended, like the inhabitants, to keep to the fringes A helicopter pilot said he and his col- leagues were particu- larly careful about the albatross, not be- cause of any memories of the an- cient mariner but because an en- counter with these in flight could be fatal for bird and heli- copter. It only remained then, in this tight little half-hour programme, for David Attenborough to bring us up to date on the moun- tain gorillas of Rwanda--they are mainly alive and moderately well but not thanks to poachers--and for Mr Soper to have a fleeting swipe at the con- servation intentions of the gov- ernment, and it was all over. And well done, too. <1Nature,>1 produced by Robin Hellier, has a lot of pace as did Horizon's The Geneva event (BBC2, 24 January) What the latter did not have was much pa- tience with the aspirant but rela- tively unlearned student of what is going on in the world of high- energy physics The main Geneva event--the identification of the W sub- atomic particle which, with the Z, will enable the theory that the four fundamental forces of nature can be unified within a single framework to be sus- tained--has yet to be an- nounced, though it is believed imminent Horizon had been patiently filming for four years. Obviously it had a lot of film and limited time to show the mighty effort of the physicists of 13 countries in overcoming the obstacles to establish the complex, gargan- tuan apparatus for the experi- ment. One thought the Horizon team made an unnecessary detour here and there. It allowed, for instance, a little chat between Mrs Thatcher and a BBC reporter, the main pur- pose of which escaped me, un- less it was to show that that lady cannot be excluded from any- thing. The main problem was, I suppose, that of getting a quart into a pint pot which, even with the possibility of two new sub- atomic particles, remains as in- soluble as ever. [] <2FORUM>2 --------------------------------------------------- When the Argentines tamed fusion --------------------------------------------------- Philip Davenport on a scientific breakthrough that shook the world FROM SECRET FILES recently de- classified by the British government under the 30-year rule we learn that the Argentinian dictator President Juan Peron contemplated invading the Falkland Islands in 1951. What inspired such reck- less aspirations? What boosted Peron's ego? A partial answer might be that he was con- fident at the time that Argentina would be the first country to exploit atomic energy for industrial purposes. For on Saturday, 24 March, 1951, on the eve of a conference of foreign ministers of pan-American states, the president an- nounced to the press, "Argentina produces atomic energy" President Peron in- troduced Professor Ronald Richter to the press as the scientist responsible for the project, and later decorated him with the Peronista Medal. The gist of Peron's state- ment, shorn of its chauvin- ism and sanctimony, was that at an atomic energy plant on Huemul Island near San Carlos de Bariloche, Argentinian scientists had re- cently achieved the con- trolled liberation of atomic energy from thermonuclear reactions. They had done this using processes analogous to those which provided the energy of the Sun. The ther- motron, as the apparatus was called, did not rely on the principle of the hydrogen bomb. Instead it utilised materitals less costly and more readily obtainable. Even in today's nuclear age such a claim would be widely reported; three decades ago it was front-page news throughout the Western world. The British press did its homework. Huemul turned out to be a small island in lake Nahuel Huapi, high on the slopes of the Patagonian Andes. The surrounding district was a national park, the summer and winter playground of rich South Americans. Ronald Richter, aged 42, was a little-known Austrian-born physicist, one of many German-speaking scientists and technicians who turned up in Argen- tina in the late 1940s. Scientific correspondents of the UK press expressed surprise rather than in- credulity at the Argentine claims. This was because the scientific elite of the Athe- naeum, on whom the correspondents relied, were well aware that research on controlled thermonuclear reactions was al- ready being furtively pursued in a few British laboratories. The scientists were hesitant to accept the claims of such a non- entity as Richter without corroboration. Reaction in the US was very different. The press blustered; the claim was "impossible under the immutable laws of nature", said the <1New York Times.>1 (such an outward display of scepticism towards foreign achievement was later to greet the news of Sputnik 1.) But behind the scenes the claims were taken more seriously. The government of the US wasted little time in funding two secret thermonuclear research projects. Labelled as Sherwood and Matterhorn, the projects were headed by Jim Tuck and Lyrnan Spitzer respectively. In view of the distrust of British security then prevailing in the US in the aftermath of the Fuchs case, the transparency of these code-names is noteworthy. During the following weeks, the world waited in vain for detailed confirmation of Richter's claims. At Peron's invitation, Professor C J Bakker, a well known Dutch nuclear physicist, visited Argentina in May 1951 to study the situation, but no sci- entific information was forthcoming. There were press reports of Argentine Army experts denouncing Richter as a "fake scientist" and his alleged discoveries as a "colossal bluff". Rumours of his arrest circulated. Official denials by the Argentine Foreign Office were interpreted as playing for time to avoid loss of face. Richter kept his end up by arranging a press visit to Huemul Island on 21 June, 1951. Visiting journalists saw buildings which they were not allowed to enter. They also saw a deep hole lined with concrete, where earlier ex- periments were to be repeated on a far larger scale. The larger experiments would be preparatory to the demonstration of a thermonuclear power station elsewhere in Argentina in 6 to 8 months time. Not until the appearance in <1United>1 <1Nations World,>1 dated May 1951, of an article by Professor Hans Thirring, entitled "Is Peron's A-bomb a swindle?", was Rich- ter spurred to put pen to paper But his rejoinder, "Argentina has no atom bomb" in the July issue of that journal, was a dis- appointment to those expecting some scientific enlightenment. There, sand- wiched between a diatribe against Thurring and a facetious denial of his arrest and imprisonment, was a concatenation of su- perficial, pseudo-scientific generalities. It bore the stamp of a charlatan; apart from the hint that the fuel was lithium-6, there was nothing at all to facilitate inde- pendent assessment of his ideas and results. In the years that followed, press speculation dried up, scientific interest evaporated, and the whole affair became regarded as a laboured, pointless hoax. Pointless, that is, to all but Richter, who had thereby acquired sub- stantial financial support and much publicity and local kudos. Then came the change of government in 1955 Peron fell from power and a provisional military government took office. The new government began investigating allegations of corruption under the pre- vious regime and among many awkward questions raised was the fate of the 1000 million pesos (#25 M) that had been allocated to the atomic laboratory on Huemul Island. Rich- ter's arrest for questioning on the night of 4 October, 1955, was reported in the Buenos Aires <1Standard>1 the following day. In true Argentine tradition, nothing seems to have been heard of him since. What are we to learn from this bizarre episode? Apart from confirmation that in dictatorships, scientific corruption flour- ishes together with the more venal kinds, perhaps it is that we should not accept the recent predictions of Argentina's early possession of an independent nuclear arsenal without some reservation. [] <2When giants roamed>2 <2Tam Dalyell recalls some scientists of a technological revolution that failed>2 ALL THAT REMAINS of the palace begun by Canute is the much reno- vated hall built by William Rufus in 1097, in which Charles I was tried and condemned, and the splendid fan-vaulted crypt below. On Thursday, 20 January, a party of ennobled scientists and industri- alists, teachers and educators assembled in that hallowed crypt to pay their last tribute to Kenrick Wynne-Jones, sometime professor of chemistry at Newcastle University Lords Sheffield, Ashby, Peart and King's Norton were among those present. The crypt of what is now the House of Commons has been the venue of many historical events. Oliver Cromwell stationed his horses there after he had had its decorations whitewashed! Suffragette Emily Davidson, who was to throw herself under the King's horse at the Derby in 1913, hid there during the census of 1911, to protest for Women's Rights. It has been the setting for the marriages of numerous MPs and the subsequent baptism of their offspring in its Welsh marble font. Never though can it have housed a greater galaxy of scientific and industrial leaders than on that Thursday last month. The occasion was historic because it was a tribute to one of the great furnace-masters of the white heat of the technological revolution of the 1960s. It is 20 years to the week since Hugh Gaitskell died. Hugh, as leader of the Labour Party in opposition, gathered a number of scientists around him to gain their advice. The great physicist Pat Blackett and crystallographer John Desmond Bernal, both famous for their science and socialist commitment, were among that number. But it was very much a dining club arrangement. When Harold Wilson succeeded Hugh Gaitskell as party leader in 1963, he swore he would not make Galtskell's mistake of surrounding himself with elite coteries of policy advisers. Even if there was little to be suspicious about, such cosiness made others suspicious. Wilson appointed Dick Crossman Shadow Secretary of State for Education and Science, and encouraged him to spearhead some 40 conferences, up and down the country, to encourage an exchange of ideas. Kenrick Wynne-Jones set up one of the first and best organised of them in Newcastle Wynne-Jones's work for the Labour Party, added to his success as a chemist, made him a clear choice as a working member of the House of Lords. Until the day he died, Kenrick worked on, chairing NATO Parliamentary Group Committees and sustaining interest in many educational causes. The senior men of science who grav- itated towards politics in the 1960s are a remarkable generation. Mentally, they have not grown old. They have remained interested in the future, and are often younger in spirit than many others who are 30 years their junior. Some writer should do for them what Bertrand Russell did for his grandfather and others in that exquisite volume <1Portraits from Memory.>1 The scientists provided the sound base from which Harold Wilson could talk about the white heat of the technological revolution in 1963, and be believed, rightly, because it was no gimmick, but sincerely meant, and potentially a huge success. Sadly it was cooled by the sterling crisis of July 1966. Although that crisis seemed serious then, compared with the present threat to the world banking system, it was small beer. I count myself fortunate in having met both generations of politicians and scientists. For a raw young MP to be confronted by Sage Bernal was an experi- ence and a half. Already suffering from physical ailment, and surrounded by some marvellous women who took it in turns to look after him in the evening of his life, he was a fount of ideas and vision. He cata- pulted us into the future with promises of electronic miniaturisation and biotechnology. He warned us of the consid- erable social upset that these advances might cause. Patrick Maynard Stuart Blackett was altogether different At first, I thought he was toweringly formidable. He had been in charge of situations for the previous half century, since he had commanded guns on the Barham at the Battle of Jutland, as a midshipman, in the First World War. Blackett also saw action in 1914 off Port Stanley in the Falklands Islands. When I met him he was marvellous to work with. I believe the technological revolution would have been better served if Blackett had been appointed to a real job, rather than to an advisory one to Frank Cousins, who became Minister of Technology. Even the most heavy-weight scientists, snobbish to the end about their colleagues, would have accepted a Nobel prize winner of Blackett's stature. What they would not accept was that vain and dreadful C.P. Snow, whose appointment as Parliamentary Secretary to the Ministry of Technology was as insulting to the scientific community as it was to the Labour Party. A fortnight after being made a minister, this raconteur said that he had joined the Labour Party simply to make sure that "they did nothing too silly". His laziness became a legend in the corridors of power. His ministerial diary for the day often consisted of a lunch at a club and little else. Snow was Harold Wilson's biggest ministerial blunder. Altogether different was Vivian Bowden, now Lord Bowden of Chesterfield, in those days a man of frenetic and driving energy. He wanted to bring to Britain the great <1Techntsche Hochscgule>1 of Germany, and laboratories like those run for Philips of Eindhoven by the famous Professor Casimir. Vivian one day told us that he had "sacked his secretary". It transpired this was his permanent secretary, Sir Bruce Fraser, one of the greatest Treasury mandarins of the day Vivian had acted without reference to his secretary of state, the Head of the Home Civil service, or the Prime Minister. Little wonder that he went back to his post of principal of UMIST. Whitehall did not understand him, and he certainly did not understand Whitehall--That was a great pity. Kenrick Wynne-Jones was altogether less turbulent He understood the art of getting along with politicians, and found a power base for himself through friendship with the Labour leaders of the day from the North, such as Ted short and Lord Glenamara. Ever constructive and logical, Wynne-Jones influenced events, and was a credit to the concept of the Life Peer I miss them all. [] <2Micro apple-cart>2 WHEN it comes to press manipulation, the Ministry of Defence has nothing on Apple Corporation, maker of the famous Apple microcomputer. The company spent some two years casting around for a successor to its best-selling computer and finally came up with a machine called Lisa named after the daughter of the company's founder Steve Jobs. Over the past few weeks, Apple has been courting the press with sneak previews of Lisa on the condition that the participants undertook not to breath a word of what they had seen until the machine was officially announced on 20 January (simultaneously around the world). So inflexible was this masterplan that when <1New Scientist>1 attempted to introduce someone who knew nothing about computers to the machine (it is claimed to be very easy to use) we were turned down on the grounds that "this would upset the timetable". Another <1New>1 <1Scientist>1 contributor was barred from the jamboree on 20 January on the grounds that he had a "hotline to IBM". IBM could not have done better. Oh yes, if you want to know our assessment read <1New Scientist>1 20 January, p 160. [] <2The sexes out of skew>2 <2David Challinor continues his research notebook from Washington>2 THE OFFSPRING of most animals are equally divided between males and females. There are, of course, exceptions. Honey bees, whose workers, although uniformally female and gene- tically identical to the queen, are infertile. A few decades ago at the US Department of Agriculture Experimental Station in Belts- ville, Maryland, only female clucks were hatched from synthetically fertilised turkey eggs. These turkeys were also infertile. Turtles provide us with a different example. The sex of their progeny is determined by variation in the incubation tem- perature of their eggs. We must expect, however, that over the years total production from a given turtle population will pro- duce males or females about equally. This assumption, how- ever, has not, to my knowledge, been tested. The discovery of an animal population with a skewed sex ratio thus triggers a search for an explanation of an unnatural condition. I would here like to give two examples of such skewed populations and to spec- ulate on the seeming anomaly. While studying the sloths of Barro Colorado Island in Panama, scientists from the Smithsonian Institution observed that the small moths living in colonies, from 10 to 50, in the fur of these mammals were sexu- ally skewed towards males. The moths (<1Cryptoses choloepi>1) are about the size of a housefly. Despite considerable research on both the two-toed and three-toed sloth, the moth's life cycle was unknown. As the investigation progressed, the researchers found that on the two-toed species males outnumbered females 3.1, and on the more common three-toed sloth it was 7:1. Only adult moths lived in the fur and there was no sign of eggs or larvae on any sloth. To account for the absence of eggs the Smithsonian scientists removed female moths, ready to lay, from captured sloths to screened cages, where the moths promptly laid their eggs on any hard surface. The researchers fed the emerging larvae, which they later found to be equally male or female, on sloth hair (on which a green algae often grows), sloth dung, and leaves from those trees on which sloths generally feed. The larvae began feeding immediately on the dung and avoided the other food. If this was their preferred food, how did lar- vae find the dung? Further experiments showed that sloth metabolism was so slow that they defecated only once a week. After patiently tracking radio-collared sloths, the scientists observed the animals descending almost to the ground from the forest canopy, where they normally live. There, hanging by their forelimbs from a vine or branch, the sloths dug a small depression in the soil with their hind legs into which they defecated. A par- tial explanation for the sexual skew of the moths became apparent when gravid females were seen leaving the sloth and laying eggs in the fresh dung. The female moths, it would seem, either have a shorter life span than males, or they are preyed upon while they lay their eggs. However, one thing is certain: whatever the reason, they do not all return to their former host. The moth's life-cycle is now partially known, but other questions arise. Why does a sloth leave the relatively safe canopy to defecate on the hostile forest floor where it is vulnerable to terrestrial carnivores? Why does it not defecate from the tree tops as monkeys and squirrels do? Among sug- gestions offered to explain this is that the sloth's behaviour is mutually advantageous to both it and the tree on which it feeds--the tree is fertilised by the dung. This may not be as far fetched as it seems, considering the low nutrient content of tropical forest soil. Another speculation is that this odd behaviour (to humans) is a genetically controlled one that goes back to the days of the giant ground sloths. Perhaps it is merely to accommodate the moths, but what the benefits are to either sloth or moth in their relationship is still not understood. My second example, although involving a very different animal, raises the same kind of questions. In 1976, the Smith- sonian supported a scientist for 16 months on the island of Aldabra in the Seychelles to study what appeared to be a static popu- lation of goat. Feral goats have inhibited the island of 150 square kilometres for at least 100 years, but unlike the exploding colonies of goats in some of the Galapagos Islands, the Aldabra goats have remained stable and perhaps even declined in recent years. Special skills and techniques are required to observe the behaviour of goats in this rugged, inhospitable environment. The researcher noticed that the adult sex ratio was significantly skewed towards males in some of the groups she was observing. The reason became apparent when she saw a young female come into breeding condi- tion. Groups of up to 14 males of all ages attempted to mount the female. Under nor- mal conditions a male dominance hier- archy would have been previously estab- lished and only the dominant male would have had access to the receptive female. No such hierarchy was observed on Aldabra. Instead all males chased and butted the female. Our scientist found evidence, although she did not actually witness it, that this violent breeding behaviour can actually result in the death of some females. At best, the nanny was under great stress and was frequently wounded by the horns of her suitors. She found more deaths among sex- ually mature females than among males, which gave a skew in the latter's favour. But if more deaths among the female goats re- sulted from the aberrant male breeding be- haviour in this population, what caused them to behave so in the first place? A possible explanation is that during the 1950s and 1960s, before Aldabra became a scientific reserve, commercial fishermen from the Seychelles living on the island hunted goats with dogs at night. Seychellois prefer the meat of female goats over that of males. The disproportionately high female mortality initially caused by hunting pressure, re- sulted in the observed sexual im- balance among the goats. This imbalance might have initiated the aberrant breeding behaviour of the males, so that the violent and sometimes fatal courtship, coupled with the inhospitable climate of Aldabra helped to maintain the imbalance. It could also explain why the goats have not increased there as they so often have on other islands. Another explanation for the skewing of sexual ratio might be that there is heavier mortality among females, particularly lac- tating ones, during times of drought. More investigations are needed to understand how the imbalance came about, even though the way it is maintained seems clear. Human beings generally consider life to function best when that ratio of male to female is relatively even. I have here given two examples of animal populations with an evident clear adult male majority. There are, however, examples of the reverse con- dition. After the second World War in Europe, adult females outnumbered adult males, because of the high combat mor- tality among men. The imbalance, how- ever, should soon disappear as the adult survivors of the war years die naturally. It is the population that seems to sustain an adult sexual imbalance that alerts our curiosity and demands an explanation. Sometimes the answer is hidden, either because it is too obvious for us to recognise or too complex to unravel. [] <2All the fun of science>2 THE British Association is organising a great day in London for young seientists on Saturday, 5 March. It has planned an exciting programme of activities for its first ever BAYSDAY which it hopes will be attended by young people of secondary sehool age from all over the country. The organisers are planning a "model hot air balloon competition" and are asking entrants to get their entries sponsored to raise money for the development of water supplies in Third World villages. (If things don't improve at home the need could be closer!) Weather permitting, though, there is to be a full-scale balloon launch with hot air--some of it no doubt coming from a "Balloon debate" and a "Question time" session. Other activities include geological workshops, a fabulous demonstration on the science of flame, a museum's quiz, a careers exhibition and a re- gional heat of the Lloyds Bank BAYS practical problem solving competition. All the activities will be at Imperial College and the South Kensingon Scientific Museums. Registration costs #1 but for further details, leaf- lets and registration forms, write to Peter Briggs, BAYS Office, Fortress House, 23 Savile Row, London W1 X1AB or telephone 01-734 6010. Hurry so that your registration is suecessful. [] <2Clunk-click-mumble>2 ---------------------------- <2Keith Dale on the myths of belting-up>2 SEAT BELTS become compulsory dress for the well-turned out driver at the end of last month. Along with the clatter of clunk-clicking up and down the nation this week, there have been the usual apocryphal murmurings about the dangers of seat belts. The typical conjecture is that if you pro- tect car driver from their mistakes you encourage bad driving. The theory of risk compensation, which has been around for years, says that drivers adjust the amount of risks they take to keep their perceived level of risk constant. Hence, if you tuck your average driver into a seat belt, the driver will take more risks to compensate for the increased sense of security. Is this true? When danger is seen or heard, drivers drive more safely. How they drive more carefully depends on the vehicle's braking and handling, night time vision and so on. The evidence is that primary safety improvements, like studded tyres, better acceleration and so on, encour- ages more cautious driving. Drivers do not take full advantage of a vehicle's improved performance. However, it is not easy to see anyone taking advantage of secondary safety features, such as seat belts, collapsable steering columns, safety glazing and pad- ded fascias. In fact, if anything, secondary features seem to do little to change driving standards. This is contrary to popular opinion. Two studies into the way that people drive and use seat belts in the United states showed that belted users jumped traffic lights and "kept their distance" only marginally more than drivers who didn't fasten their safety belt. I decided, with colleagues at Birming- ham University's Accident Prevention Unit, to investigate this phenomenon. We looked at the relation between a car's speed and the use of seat belts in the UK. After we had sampled 3000 vehicles at the three sites, we found that there was virtually no difference in the speed between the two classes of drivers. There is no evidence, to date, that making people belt-up turns them into worse drivers. The general evidence that is available suggests that more advanced driv- ing instruction, plus better signs, signals, street lighting and road marking would cut the accident rate. So, belt-up! [] <2Psychological warfare>2 ------------------------------------ Lynne Murray watches in a state of amazement KNICKERS are being twisted even more than usual in a recent <1Bulletin>1 <1of the British Psychologtcal Society>1 (vol 35, p 329 <1et seq.>1). The bulk of the issue is devoted to an acrimonious article full of names and packdrill, a furious rebuttal from the accused, a reply from the accusers, and, tucked away at the back, a letter from the accused replying to the reply. It looks like something out of a Marx Brothers sketch ("the party of the first part. . . " one, which includes the immortal line "Sanity clause? There ain't no sanity clause!"), but the humour of the occasion is dampened by the fact that this maelstrom of accusal and refutation, doing nothing to enhance the good name of psychology in general or the British Psychological society in particular, involves the principle of confidentiality of psychological tests coupled with the issue of a man sent to prison for a crime that--perhaps--he did not commit. The case centres around a Mr X, accused with several others of setting up a bogus merchant bank used to conduct fraudulent transactions. Although Mr X was a director of the "bank", his defence was that he acted in good faith; indeed, said the defence, such was his faith in the word of his associates that he had invested, and lost, his own money in the venture, always acting on the advice of his colleagues', without ever ques- tioning it. Such naivety does not fit the con- ventional image of a merchant banker, but rather suggests the innocent party in a con- fidence trick. Could it really be so easy to pull the wool over Mr X's eyes? Defence counsel called in psychologist Olive Tunstall to give an independent opinion. Using a comprehensive selection of stan- dard psychological tests between October and December 1979, Tunstall came to the conclusion that Mr X had an IQ of 80 and a reading comprehension age, in English, of 71/2 years. It happens that Mr X's preferred lan- guage is French, but even in that tongue he could not write or spell with any normal level of competence and his grammar was almost non-existent. Before becoming a merchant banker, he had worked as a bar- man, waiter and later a salesman. You can almost see learned counsel sitting back with a sigh--"the defence rests, m'lud. My client is too stupid to have committed these crimes." So, in January 1980, the psychological evidence was presented in court, and duly challenged by the prosecution and by coun- sel for one of the other defendants. They painted a picture of Mr X as a really bright cookie--bright enough not only to run a crooked merchant bank, but to pull the wool over the eyes of the psychologists. Enter expert witness Dr Alice Heim, a psy- chologist who said that, indeed, Mr X was faking his test answers. Counter attacking, the defence brought in a consultant neu- rologist who testified, on the basis of medi- cal records and EEG tests, to the likelihood of brain damage in Mr X in childhood, and a second clinical psychologist, who had made a special study of faking and said that Mr X couldn't fake an IQ test to save his life, or words to that effect. It looked as if the defence had made its point. But in April 1980 the lengthy trial proceedings ground to a halt because of allegations that at- tempts had been made to bribe the jury. A new trial was called, and early in 1981 the roundabout started up again. Now, it was suggested that Mr X's alleged subnormality did not seem consistent with a lifestyle that involved successful gambling in London clubs at a complicated card game called Kalooki, savings of #30 000, and familiarity not just with English and French but with Hebrew and Arabic as well. More psychologists were brought in to assess Mr X, who must by this time have been suffering from IQ test overkill. All said he was of low intelligence, and as a trump card the defence brought in Professor Hans Eysenck to consider all the evidence. He agreed that the evidence in support of the assessment of Mr X's low intelligence was overwhelming--but the court refused to hear his evidence. Heim again presented her view that the accused was faking, and added the comment that from her obser- vations of his behaviour in the witness box he seemed to be of average intelligence. Now, despite vigorous protests from the psychologists involved, the tests completed by Mr X were photocopied and handed round the court, to officials and jury. It was put repeatedly to the psychologist witnesses called by the defence that whatever the tests might say those present could form as good an impression of Mr X's intelligence from observing his behaviour in the witness box. Three of the psychologists reporting for the defence in this case (Olive Tunstall, Gisli Gudjonsson and Lionel Haward), to- gether with Eysenck, whom the court refused to listen to, were understandably piqued by the stance taken by the court. They resented its reluctance to accept that the opinion of a psychologist based on test evidence was more valid than the opinion of the man in the street--or on the jury--based on observation, and they were annoyed that the court failed to recognise that the tests involved were as confidential as those carried out by any other medical practitioner. Both these points, strongly made by Olive Tunstall and her colleagues in their <1BBPS>1 article, are directly relevant to the continuing attempts by psychologists to achieve the sort of professional recog- nition given to doctors concerned with the physical, rather than mental, well-being of people. Mr X was found guilty and sentenced in May 1981, and it is difficult for anyone who reads the story as laid out in the pages of the <1BBPS>1 to see how his guilt could have been established beyond reasonable doubt, in view of the conflicting scientific evi- dence. It is unfortunate that the team headed by Olive Tunstall feel the need to launch into a personal attack on Heim, however, saying that "we consider that Heim acted in such a way as to reduce the credibility of the profession". In her reply, Heim stresses the uncertainties of the case, and emphasises the possibility that Mr X's apparent subnormality may have been linked to dyslexia, rather than a low IQ. All of the combatants in this psycho- logical war are clearly competent psycholo- gists who believe they have made the correct interpretation of the evidence. But mud slung in such quantities and with so much acrimony is bound to stick some- where, and the overall impression being given is that while the law may be an ass, the profession of psychology is an even bigger one. [] <2LETTERS>2 <2Peace in our time>2 Once in 40 million years, once in one million years--what <1are>1 the chances of a major accident at the planned Sizewell pressurised-water reactor in Suffolk (This Week, 11 November, p 343)? Surely the main short-term risk to any form of energy-producing installation (conventional or nuclear) is war (conventional or nuclear)? Or do the nuclear powers-that- be believe that they have won for the world not only peace in <1our>1 time, but peace for a million years and more. Nuclear power stations <1do>1 make tempting military or terrorist targets, as the sabotage at South Africa's first nuclear power station at Koeberg near Cape Town at the end of last year clearly showed. Could it only happen here? <1John Comrie Greig>1 <1Editor>1 <1African Wildlife>1 <1Somerset West>1 <1South Africa>1 <2The pen and>2 <2the pendulum>2 The twin-elliptic pendulum drawing machine described by Judith Mirzoeff in "A wealth of mechanical patterns" (Forum, 23 December, p 854) is, in fact, more widely known as the twin-elliptic harmonograph. Engineer Charles Stratton's claim to have been "the only person to have made money from such a machine" is difficult to substantiate. For well over a century the design has been available whilst in 1909 the Science Museum, for example, acquired the example to be seen in the <1Computing Then and Now>1 gallery, purchasing the cheaper of the two production models made by Messrs Newton and Co. and fully described in the firm's literature Stratton's brainchild differs from the Newton model only in having the second pendulum attached to the pen instead of hanging below the main pendulum under the table. The principle of operation is identical. Readers willing to invest 12p can buy a leaflet How <1to make a twin-elliptic>1 <1harmonograph>1 from the Science Museum bookshop. <1J. V. Field>1 <1D. J. Bryden>1 <1Science Museum Library>1 <1London SW7>1 <2Oh gear!>2 The automatic transmission for bicycles (Technology, 6 January, p 23) unfortunately fails in the common occurrence of a person, cruising quickly on a level road, and then wishing io increase speed. Pressing heavily on the pedals, the bicycle would then do what is not required, namely change down. <1Larry Curley>1 <1Huntingdon, Cambs>1 <2Hypnotic error>2 In the article "Hypnosis on trial" (6 January, p 12) Professor Diamond is made to make a quite extraordinary statement; "The use of hypnosis on a potential witness is tantamount to the destruction of fabrication of evidence." This is due to an unfortunate misprint: Profesor Diamond actually referred to " . . . . the destruction <1or>1 fabrication of evidence". The article goes on to refer to whether hard scientific evidence about hypnosis as an aid to the recall of memory can "help the police to use hypnosis safely". I hasten to point out that it is not envisaged that in the UK police officers themselves shall be trained to use hypnosis, as in some states of the US. Such discussions with the Home Office that I have had on the question have made it clear that when their guidelines to the police are finally formulated the limited use of investigative hypnosis will be exclusively in the hands of trained and independent professionals such as clinical psychologists. <1H. B. Gibson>1 <1Chairman>1 <1British Society of Experimental>1 <1and Clinical Hypnosis>1 <2Leave us>2 Why do autumn leaves fall? (Monitor, 2 January, p 21) 1. Autumn comes before winter. 2. Every winter we have high winds. 3. Every winter large objects with large surface as get blown over (or turn up by the roots). A tree without leaves has a smaller surface area as compared with a tree with leaves which has a large surface area. Ergo, every autumn those trees with any sort of seasonal sense at all shed their leaves, which are pretty useless anyway when there's not going to be much Sun around, and ride out the storms on bare poles. Is this sufficient for my Nobel Prize? <1Dudley Long>1 <1London W1>1 <2Astronomical>2 <2insinuation>2 I deeply resent Michael Rowan- Robinson's insinuation that I have been "disreputable" in my use of a review article by Bernard Carr and Martin Rees in writing my book <1The Accidental Universe>1 (Review, 20 January, p 186). I was commisioned by Cambridge University Press specifically to base a book on this review and sent a copy of the manuscript to Bernard Carr a year before publication, I was faced with the difficult task of dividing credit between Carr and Rees, and the original authors whose papers they reviewed. Thus, I credit Carr and Rees with Chapter 2, but Carter, Silk and Dyson with Chapter 3. If I have thereby diminished Carr and Rees's very valuable contribution to this subject, then I am sincerely sorry. Such was not intended. What I find offensive is Dr Rowan-Robinson's implications that somehow I am claiming the credit for this work. That is nonsense. Very little of the material in <1The Accidental>1 <1Universe>1 is mine. I just wrote the book. <1Paul Davies>1 <1University of Newcastle upon Tyne>1 <2Explosive rats>2 I don't believe Ariadne's story (20 January, p 212) about explosive rats (Knallratten?). Plastic explosive burns quietly, as I once demonstrated in an admiral's ash- tray, believing the stuff to be an enemy incendiary compound. Detonation would have wrecked my promotion prospects. <1Peter Danckwerts>1 <1Cambridge>1 <2Bits of skirt>2 Sixteen years ago, it was pointed out <1INew Scientist,>1 vol 32, p 530) that a milliskirt ends three inches above the knee, and microskirt six inches above, a nanoskirt nine inches above, and a picoskirt one foot above. It is now essential to hold in mind that a femtoskirt ends fifteen inches above, and an attoskirt eighteen inches above the knee. Unfortunately gigaskirts, teraskirts, petaskirts and exaskirts are at present more fashionable than attoskirts. <1I. J. Good>1 <1Department of Statistics>1 <1Virginia Polytechnic Institute and>1 <1State University>1 <1Blacksburg Virginia>1 <2ARIADNE>2 We have to get this clear once and for all and it is the question of what Neil Armstrong said when he landed on the Moon. I have had many letters about the subject and the correct version appears to be, balancing many a quoted sentence against another, "It's one small step for man, one giant leap for mankind." What he <1should>1 have said was, "It's one small step for <1a>1 man," but he muffed his lines, as many an actor on a less impressive stage has done. The Iine was supplied, most people think, by NASA for him. There is a measure of dubiety (I like to use American ambassadorial language on the appropriate occasion) about the first word, "It's". It could have been "That's", mangled by the transmission from the Moon. All this is culled from letters from people who had the forethought to record the event. I am grateful to them, but I hope the subject can now be dropped. [] OVER the years I have learned to stop wincing at the description of someone having a drink problem. But now I see, from a recent incident, that people are not ill any more. They have a health problem. It may even be specific, such as a lung problem. Do the unemployed have a work prob- lem? Shall we soon abolish death and refer to someone dead as having a life problem ? [] <2WHO WOULD change places with Sir>2 Frank Layfield, the inspector who is presiding over the public inquiry into whether or not to build a PWR reactor at Sizewell? Of course, he will have to cope with demonstrations, many of the less sober sort, but, as far as I have heard, he is doing this with massive inscrutability. They are not the reasons for the tor- ture that I would be suffering in his place. What would turn me either to stone or to desperation would be the boredom of hearing the same thing over and over again. Having read much of the evidence so far, I am already chanting the words of the CEGB opening witnesses, under my breath. Lord Silsoe, QC, opening up the CEGB campaign and taking two and a half days to do it (there's nothing like Latin for spinning words out), said that the board's case had three main points. A PWR was economic, displacing old plant; it was a good thing because it used other fuel than coal, or, rather, it was in line with the Board's policy of fuel diversification; and that the technology of the PWR would be an excellent base for future operations. The next witnesses, on behalf of the CEGB, said that there were three main reasons for going for a PWR. Displacing old plant was a good idea, so was fuel diversification and obtaining the tech- nology necessary would be an advantage for the future. I have no doubt that the objectors, when they arrive on the scene inside the Maltings, will follow the same line, striking similar monotony but different notes. The hearings are likely to go on for months. Music lovers should not start feel- ing apprehensive, for the whole circus moves to London when it is time for the Aldeburgh festival. [] THOSE who are struck all of a heap when faced with a bill from British Telecom for some trifling work carried out in their homes may like to know that there is a Telecom instruction sheet about charges. It is coded D7 CO 100. It has this instruction over the list of moneys. (TRC means time related charges, just in case you were not aware.) --Method of calculation. The TRC is calculated on form A2317 from the <1Total>1 number of manhours (ie not per man) spent at or in the locality of the customer's premises only (travelling time should not be included) at the following Hour Charge Rates." There then follow the rates for normal working and various categories of overtime. The charges are for time, as the instruction sheet clearly says without ambi- guity, and it does not matter how many men are concerned. However, I have been informed that some, even most, regions of British Telecom disregard the instruction. If two men do the work, they double the charges and so on. This can mean that a subscriber can be charged far more than he should be and I gather that some regions even add in the hours that trainee engineers work as well. Up to now, British Telecom, sometimes attacked, sometimes praised in this maga- zine, has kept a dignified, appreciative, affronted, hurt or tactical silence, I cannot tell which. I hope, though, that the organisation will break its silence with an observation or two this time. [] THE THREAT of snow, and the treach- erous and icy driving conditions which it creates, has inspired Daedalus to devise a thermal counter-measure for the motorist. He recalls that a petrol engine is only about 20 per cent efficient; most of the energy of its fuel appears as heat in its radiator and exhaust. So a car developing 30 horse- power at 60 miles an hour is releasing some 90 kW of heat continuously into the air. If it could be transferred to the road instead, even modest traffic would keep the road so warm that ice could never form. So Daedalus is inventing the foam- blowing car. A really heavy-duty bubble mixture, made from modern viscoelastic polymer solution, will be drip-fed into the exhaust and radiator-outlet of the vehicle. It will leave behind it a carpet of hot foam spread over the road. For a typical car, the carpet will only be about 2 cm thick, and will be quite short-lived but in the few seconds it lasts before collapsing it will transfer most of its heat to the road. With only one car every ten seconds, every square metre of road surface will receive some 200 W continuously. Thus will the terror of black ice be banished. There will be many other advantages. Lead- laden exhaust fumes will dissolve in the bubble-fluid, and will be washed down the roadside drains instead of polluting our lungs. Road- cleaning will be quite automatic too. Drivers will be inhibited from driv- ing too close to the car in front of them, for fear of being swamped in its foam. They will have to leave a safe distance for it to spread out and to subside. But of course the foam- system had better switch itself off auto- matically at low speeds. Otherwise every traffic jam will gradually vanish beneath a rising tide of its own foamy output. []