Untitled - Bedales Schools

Contents:An Interview with Harry Pearson……………....………………...……………………..page 2Eckersley Lecture Review — by Harry Pearson….…………….………………..……..page 36-2 Trip to CERN — by Felix Grey….…...……….….………..………..……...…...….page 4Final Century? — by Yamez Collopy ……..………………………….…………...…...page 6Spring at the North Pole — by Maia Bryant.……………..….…………………….…...page 8IT and the Environment — by Justin Latter…….….…...….……….…………..…........page 9Joseph Rotblat — by Harry Pearson……………..……..……………………………..page 14A Brief History of Plastics — by Don Cooper…………..…..…………………..…….page 15Bedales: Sustainable Buildings — by 6-2 physicists……...….………………..…..….page 19Cabo Frio — by Camila Barata………..………..………...……….…………………..page 21Interview with Tony Marmont……………………..…………………….…....………page 22Global Warming? — by Gary Skinner…….……….….………...…….….……...........page 25Hydrogen Fuel Cell Car — by Alistair Larsson and Ashley Bray….…...….….……...page 26Recycling — by Paul Farley………………..……..…………………………..……….page 27The Science of the Sun — by Alistair Barrie……….…………………….…………...page 306-1 visit to Thorpe Park………………………………………………………………..page 32Stem Cell Research — by Honor Eldridge…………………….……….……...……...page 34Technological Advancement of Footwear in Running — by Lucienne Harrington..... page 35How Aspirin Works — by Zoe Riddell ………..……..……………………………….page 38The Mathematics of Population Growth — by Philip Robinson………….….……….page 39The Death Penalty — by Honor Eldridge………………..…….……...…………..…..page 42Photograph Quiz………………………...……………………………………………..page 43The B-Sci Crossword…………………...………………….………………………….page 44Front Cover: Richard SinclairContact B-Sci: rsinclair@bedales.org.ukEDITORSCharlie AaronsonYamez CollopyFelix GreyZoe RiddellRichard Sinclair

6-1 Biology Trip to Marwell Zoo

The Bedales Science Magazine

e set out, six months ago, to produce a ‘Global Warming Special’: a B-Sci that would lookW at the issues surrounding global warming from a local as well as a worldwide perspective.We were helped on our way by Old Bedalian Simon Alldridge’s fascinating, if unnerving Civics, inwhich he revealed some of the details behind his environmental work with governments around theworld. The unnerving side of this talk was partly created by Simon’s resignation to the inevitabilityof major problems arising in the very near future due to global warming, and his reminder thatChernobyl brought us just minutes (or was it seconds?) away from a catastrophe that would haverendered most of Europe’s water undrinkable for hundreds of years to come. We later had an assemblyon a similar theme by Professor Tony Marmont which gave us the viewpoint that whilstthings might be bad, there is a lot of current technology which, if used to its full effect, couldgreatly reduce man’s impact on the environment. For a full interview with Tony, see page 22.For the last 29 years Bedales science has been enriched and enlivened by the presence of HarryPearson, who leaves at the end of this term. It is impossible to say how many pupils have beenswitched on to chemistry by Harry and how many have benefited from his remarkable subjectknowledge, but I know that all his students recognize that being taught by Harry is something quitespecial that goes beyond his wizard-like ability to conjure up an explosion at every available moment.In recent years the school has benefited greatly from Harry’s contacts within the scientificcommunity. This year, the Eckersley Lecture was given by an old friend and colleague of Harry’s,Professor Brian Johnson, ex Master of Fitzwilliam College, Cambridge. Entitled ‘Small is Beautiful’,the lecture revealed the intricate world of nanotechnology and the weird and wonderful thingsthat are currently being developed. See page 3 for more details. Meanwhile, in the autumn term wewelcome Geoffrey Rishman (from Chislehurst and Sidcup Grammar School) to succeed Harry asHead of Science and Chemistry.Finally, B-Sci says a fond farewell to another great editorial team. Charlie, Felix, Yamez and Zoehave worked tirelessly to track down stimulating and relevant material for the magazine. We wishthem every success as they move on from Bedales.1

An Interview with Harry PearsonCan you give us a short summary of your academic work beforejoining Bedales?I did my PhD at University College London. My Thesis title was`Slow Rotation about Carbon–Carbon Bonds`. Using nuclearmagnetic resonance (nmr) at low temperatures, quite hard at thattime, I was able to find out about the sizes of various groups inorganic chemistry. I then moved to the California Institute ofTechnology where I worked in a big group who were pioneers inlooking at Carbon 13 nmr, again technically difficult needingstate of the art equipment and heavy computing facilities to gatherweak radio signals. Again the aim was to find out about molecularshape – as reactivity depends on shape. Then spent two years at Liverpool as ICI Research Fellowstudying the structure of porphyrins using nmr – carbon.What’s your favourite experiment/lesson?I like heating potassium chlorate, testing for oxygen, and then telling the students they must never letthe splint touch the molten material. Always the splint manages to touch when I do it and the testtube suddenly looks like a rocket. I run to the fume cupboard holding this rocket at arm’s length. It’sgreat fun.Who is/are the most impressive people/scientists you have been involved with?My PhD supervisor, Prof Edgar Anderson, is one of the most impressive people I have met. I havealways admired him for his erudition; he has been a great mentor and friend for nearly 40 years. Ihave two friends my own age, both German, who have had a big effect on my life. Prof Peter Vollhardtat the University of California at Berkeley, and Prof Stefan Berger at The University of Leipzigare both renowned in their fields of synthetic organic chemistry and nuclear magnetic resonancespectroscopy respectively. I have been able to spend big chunks of time, while at Bedales, workingwith these people: I hope the stimulation I have received from these times has rubbed off on how Ihave taught my students here.What changes have you noticed in Bedales over the past 20 years?There is more paperwork, more accountability, more of a business approach to education, more politicalinterference. Understandable in some ways but ultimately I feel education has suffered. It remindsme of Ivan Illich’s dictums such as the more we spend on schools the worse education becomes.It may be I am just getting older.What are your retirement plans? Why Brazil?I have a wife and step children in Brazil and I need to go there. I am planning to work in a universityenvironment with the Erasmus Mundo international exchange programme. I am not retiring.What’s your favourite dance routine?I started dancing in 1994: a wonderful young Brazilian girl called Solange Dias taught me how todance Lambada. I remember, having mastered the basic step, doing, for the first time, a turn. To do aturn in any dance, keeping in rhythm, and ending up with your feet in the right place still gives me athrill. It’s like heating potassium chlorate. Another friend from that time was Jo Koniak who hassince married Solange, became UK Salsa champion and, I think, is involved with the new BBC danceseries as a coach.Have you enjoyed being at Bedales?Yes very much. I have worked with some great colleagues and it has been a privilege to teach someof the people I have. It is especially pleasing to see ex students making their way in the science world –people such as Alan Spivey, Nick Levinson, and Sebastian Zonte are all doing impressive things.2

The 2006 Eckersley Lecturentitled `Small is Beautiful` Prof JohnsonE started by talking about `Big is Beautiful` ashe mentioned such technological wonders as the`Titanic`. He then worked his way from the discoveryof the electron through to the use of siliconchips in the 1950s to build micro-circuits using`micro-lithography`. The scale used was at a millionthof a metre (a micrometre). About this time ina famous lecture `There’s plenty of Room at theBottom` given by Richard Feynman at Caltech, hesuggested that it might be possible to build eversmaller machines going down to the manipulationof individual atoms and molecules. These machineswould be made of a few thousand atoms. It wasnoted that physical phenomena such as surface tensionand Van der Waals attraction would becomemore important for such assembly.Professor Johnson (left) with Harry PearsonFeynman argued that these machines would mimic conventional machines but would be at the molecularlevel and able to carry out functions within the body. Prof Johnson pointed out that at thesescales surface effects would be important - effects such as hydrogen bonding, hydrophobicity etc. Ofcourse many of these effects have been known for a long time and are responsible for the folding ofproteins, or the replicating of DNA. The scale talked about here is the nanometre scale, a thousandthof a micrometre. Although `nanoscience` and `nanotechnology` are new terms and not always easy topin down it was pointed out by Prof Johnson that colloidal gold had a deep red colour and had beenused in ancient times; red colloidal gold is made up of nanoparticles of less than 100nm; as the particlesbecome bigger the gold starts to become yellow.The lecture then headed off in the direction of the symmetries adopted by groups of atoms with particularemphasis given to the role of the Platonic solids and their interconnectedness and their role innature. The ancient material diamond is made of a huge number of carbon atoms arranged tetrahedrallybut can also be viewed as interlocking cubic structures. The recently discovered new form ofcarbon is `Buckminsterfullerene` and can be viewed as a football – the 60 points at the corners of thehexagons and pentagons are where the 60 carbon atoms are. The inside of this `football` is bigenough to be able to enclose some atoms or ions depending on size. This `idea` could be put to importantuse. Thus Prof Johnson’s lab have been able to synthesise the `open` form of Buckminsterfullerene,into tubes, called nanotubes – it is useful here to think of the carbon rings arranged like achicken wire. Their methodology was to use bimetallic nanoparticle catalysts anchored onto silica.They have further been able to carry out similar reactions using simple and common materials likenickel or iron stearate to make carbon nanotubes which encapsulate the metal – picture a wire insidea carbon sheath. These products have applications in the electronics industry and elsewhere.Prof Johnson’s relaxed and expansive style, and his way of bringing in members of the audience, aswell as putting science into a wide context, was very much in the spirit of what the Eckersley Lectureis meant to be about.Harry Pearson3

6–2 Physics Trip to CERN, Genevavery year for the past 7 years, the physicists of 6–2E have gone to Geneva for a long weekend to visitCERN, the biggest particle accelerator and particle physicsresearch establishment in the world. It employs about3000 people who range from physicists to engineers totechnicians, but some 6500 scientists – half the world’sparticle physicists – use CERN for their research. Theyare currently constructing the Large Hadron Collider(LHC) by installing new accelerators and detectors in thealready existing 27 km circular track 100 m below theground, which has been used for lower-energy particleacceleration before.There were six of us students (unusuallyfew) as well as Tobias and Ransi. Wearrived in Geneva on 10th February andwhen we got to CERN we met up withMaria Hansen, a particle physicist earningher PhD at CERN, and her boyfriendSteve, who was over from Bristolwhere he lectures in Physics. They tookus to view the CMS (Compact MuonSpectrometer) detector currently underconstruction.The LHC will work by accelerating particles to very high energies, 14 TeV. As CERN puts it: “ATeV is a unit of energy used in particle physics. 1 TeV is [1,000,000,000,000 eV] about the energy ofmotion of a flying mosquito.What makes theLHC so extraordinaryis that it squeezes energyinto a space abouta million million timessmaller than a mosquito.”Once the particles havethis energy they reachspeeds very close to thespeed of light and thenare made to collidehead-on with anotherbeam of particles withthe same energy insidea detector. When they collide, the particles – protons in this case – are annihilated and new, highenergyexotic particles are formed from the pieces of the old ones; so by looking at what is formedafter the collision physicists can work out what the original particles were made of as well as observethe new ones. Four detectors are being built around the circular track, each looking for a differenttype of particle, and it was the CMS detector that Maria and Steve took us to see.4

The scale of it was breathtaking. The detector consisted of huge ‘disks’, about 30 m in diameter andone or two metres thick, packed full of intricate individual components that – when all fitted togetherto a tolerance of a fraction of a millimetre – would work as a detector. These enormous feats of precisionengineering and electronics are as staggeringly large as the particles they are going to measureare incredibly small. The hunt will then be on for the Higgs boson amongst other potential breakthroughsin the world of particle physics. It was also the perfect time to go to the detectors, as nextyear they will be 100 m underground and no visitors will be able to see them.Next day we went to the CERN visitor centre and theMicrocosm exhibition of CERN’s work, and then tothe new Dome across the road, where there was anEinstein exhibition. It was Ben’s 18th birthday thatday and we had good time celebrating it in the evening,mostly in Les Brasseres with towers of beer.The following day we went up to the Jura Mountainsand had a French market lunch after tobogganing andsnowball fights. So it was great trip; enjoyable aswell as eye-opening and fascinating.Felix Grey 6-25

The Final Century?t the end of World War II a group of scientists based in Chicago, many of whom had worked atA Los Alamos, founded the Bulletin of Atomic Scientists. The cover of each issue was a clockface, the closeness of the hands to midnight indicating how close the human civilisation is to destruction.The bulletin is still published and the clock is now closer to midnight than it was during eventhe 1970s, when the Cold War was at its peak. Many scientists today believe that mankind may notsurvive the 21st century, come our downfall from the environment or from ourselves.The first threat that springs to mind when people think of global destruction is that of nuclear war.The nuclear stockpiles during the 1980s were equivalent to 10tons of TNT for each person in America, Russia and Europe,and today it is predicted that it will be another ten years beforeAmerica’s arsenal falls even to two thousand nuclear warheads.Furthermore, those warheads that are decommissioned will notbe destroyed irreversibly but merely held in storage. The collapseof Soviet Russia has done little to help the nuclear situation.“We have slain the dragon, but are now living in a junglefull of poisonous snakes”, said James Wolsey, former directorof the CIA, referring to the turmoil of the post Soviet era. Ifterrorists were to obtain an old Soviet warhead (of which thereare thousands yet to be decommissioned) or to construct theirown (which is shockingly easy, given sufficient uranium-235), no amount of anti-ballistic missilesystems – as are currently being developed by the US – would be able to stop the low-tech deliveryof a warhead by truck into a major city.The other weapon that could destroy our civilisation is a bio weapon. The US, UK, Russia and evenSouth Africa, to name but a few, have all had biological weapons programmes attempting to modifyorganisms to make them more virulent and more resistant to vaccines. So far the few terrorist attacksusing biological weapons have been largely ineffective, but this is more due to the unsophisticatedways in which they were released than to a lack of deadliness of the weapon itself. In July 2001 anexercise entitled ‘Dark Winter’ was carried out in the US, simulating the effects of a small terroristattack releasing smallpox. The exercise concluded that in such an attack three million people wouldbe infected. It would also be incredibly easy to manufacture such weapons. The US Academy ofSciences released a report in 2002 claiming that just a few individuals with specialised skills and accessto a lab could produce such lethal pathogens, and that they could be manufactured using equipmentthat is available commercially for purposes such as beer production. However, a terrorist attackis not the only way in which biological weapons could be released, for as long as countries continueto carry out biological weapons research and to stockpile pathogens, there is a risk that some may bereleased entirely by accident. In 1992 Boris Yeltsin admitted what had long been feared: that 66mysterious deaths in Sverdlovsk in 1979 had in fact been caused by anthrax spores leaked from aRussian biological weapons lab.This year’s Eckersley Lecture was on nano technology and although the ideas that Professor BrianJohnson talked about seemed harmless, there are fears that should the field advance further, it couldbecome extremely dangerous. Scientists hope that some day we will be able to produce tiny selfreplicatingnano machines capable of entering the human body for medical purposes. What somefear is that should these nano machines be released they might begin to consume surrounding organicmaterial in order to self-replicate. As Eric Drexler writes: “They could spread like blowing pollen,replicate swiftly and reduce the biosphere to dust in a matter of days … We have trouble enough controllingviruses and fruit flies”. This theory is known as the ‘Grey Goo’ scenario, named after the‘dust’ that the biosphere would be reduced to.6

The last, and perhaps the most subtle, way in which the human civilisation might cease to exist is ifwe ourselves cease to be human. Currently we use drugs such as Prozac to counter depression andRitalin to dampen hyperactivity, but some believe that other drugs could be developed that narrowand impoverish the range of human character, threatening the very essence of our humanity. Alreadythe hormone PYY3-36 has been used to eliminate feelings of hunger, and the region of the brain onwhich the hormone acts also influences behaviour such as sex drive and sexualorientation. In his book Beyond Freedom and Dignity, psychologist B.F.Skinner predicts that a form of mind control will be necessary in order to preventa breakdown of society and that ‘conditioning’ of the entire populationwill be essential for a society in which all members are content and that nonewish to destabilise. The thought of a world in which the population is rendereddocile and law-abiding by ‘designer drugs’ and where genetic interventionis used to ‘correct’ extremes of personality forces one to think: at whatpoint do we cease to be human?The above means of destruction are all highly scientific and technologicallyadvanced, but does that mean that science is becoming too dangerous? Onepossible way to avoid our destruction would be to slow down or stop all scientificprogress. It is thought that should scientific research be halted we would never be able to gainthe technology necessary to destroy ourselves. However, as with many things, it is a balancing actand one must consider the enormous benefits of science along with the risks. It is also extremelyunlikely that any nation will ever halt its scientific research, for fear of being overtaken by, andthereby left at the mercy of, any rogue state that chose to continue its scientific advancement. It istherefore left to the scientists undertaking such research to ensure that their discoveries and creationsare not used in the wrong way.Many talented scientists have failed at this task, such as Fritz Haber who produced chemical weaponsfor the German military during World War I. There are many others though who have set a shiningexample to the world and used their influence as renowned scientists for truly noble purposes. AfterWorld War II many scientists, some of whom had worked on the Manhattan project, turned againstthe American nuclear programme and went to great lengths to stop the build-up of nuclear arsenalswith initiatives such as the Russell–Einstein Manifesto and Pugwash.As long as scientists do not lose their morals whilst walking the road of scientific discovery it seemsthat there is still hope we shall survive the next century.Yamez Collopy 6-27

Spring at the North Polehere’s a lot at the North Pole which is nothing like anything you might expect… The ice is onlyT two metres thick and it moves all the time – in fact cracks five metres wide just suddenly appearovernight. And when you are flying over the ice to get to the North Pole, you suddenly realise thatit’s not anywhere as solid or as safe as you’d like it to be … because below that ice is 4000 m of inkyblack cold water. (The Titanic comes quickly tomind!!)Other facts – well it’s daylight for 24 hours a day atthis time of year. And I mean daylight – the lightdoesn’t just change one bit to tell your body it’s themiddle of the night. And you can only get to theNorth Pole for a few weeks a year when it’s mildenough (–35ºC!) to survive but cold enough to keepthe ice together so that Russian cargo planes andhelicopters can land. The ice is tested by dropping atractor out of a plane and seeing if the ice holds it!There’s a Russian base camp at the 89th degree fromwhereall expeditions set off and walk the last degree to thePole. Food (salami, cheese and rye bread – oh, and largeamounts of Russian vodka!) is provided for guests, andif you get caught out by the weather they’ll put you upovernight in tents and sleeping bags. Might sound a bitprimitive – but then you should see the loos…It’s pretty busy up there at the moment – we just missedPrince Albert of Monaco who went from the camp to theNorth Pole by dog sled. His special huskies all had royalcoats – the real thing sleeps out overnight in –40ºC. Anddid you know that huskies can pull sleds for seven hoursnon-stop?Not a polar bear in sight that far north – infact nothing in sight but ice and snow; asour guide said, any wildlife that appearsdefinitely got lost on the way or, like our huskies, wasflown in by Russian aeroplanes. For aircraft aficionados weflew to the base camp in an old (very old!) Russian military8

airplane called an Antonov. Forget safety – seat belts don’twork, they still smoke on board, it sets off before you areseated, the huskies share the plane with you and so do theoil barrels for the fuel at the camp!! And this is a pretty bigplane landing on an ice runway that you can’t even seeuntil the last minute!!Did I like it? Really loved it. It’s bleak and beautiful andcompletely silent. And that feeling of being right on top ofthe world when the GPS says 90 degrees is just somethingelse.But there are problems – really well publicised are the effects of global warming and year-by-yearshrinkage of the polar ice caps. Polar bears will soon be on the endangered species list because theirfood sources are dwindling as the ice melts. Fishpopulations are changing and indigenous Arctic peoplelike the Inuit are finding it increasingly hard to maintaintheir traditional way of life.I was privileged to see and experience the Arctic – Ihope the pictures give you just a little feel for it.Maia Bryant 6–1IT and the EnvironmentQ: What takes 240 kg of fossil fuels, 22 kg of chemicals and 1500 kg of waterto produce?A: A personal computerhis is based on a standard PC with a Cathode Ray Tube (CRT) monitor and weight-for-weightT is greater than for cars or fridges, which consume roughly their own weight in production. Thisenvironmental impact is offset somewhat by the fact that the running costs are less than for cars, butit is still significant. Minimising the use of electricity is clearly a good way of reducing the negativeenvironmental impact, and simply switching to Liquid Crystal Display (LCD) screens will help asthey use half the power of CRTs.Most PCs come with a plethora of power-saving features enabling the unit to ‘spin down’ harddrives, put monitors into standby mode and to ‘hibernate’. These devices were the by-product of designerstrying to avoid blackouts in places like Silicon Valley. However, considering ways of cuttingpower usage is only a very small part of what we can do to reduce the impact of IT on the environment.9

PC hazards and the lawHAZARDOUS WASTEComputers and their components are also potentially hazardous.Some examples of chemicals found are: 1. Lead in CRTs andsolder; 2. Arsenic in older CRTs; 3. Antimony trioxide asflame retardant; 4. Polybrominated flame retardants in plasticcasings, cables and circuit boards; 5. Selenium in circuitboards as power supply rectifier; 6. Cadmium in circuit boardsand semiconductors; 7. Chromium in steel as corrosion protection;8. Cobalt in steel for structure and magnetivity; and 9.Mercury in switches and housing.1. Lead in cathode ray tube and solder2. Arsenic in older cathode ray tubes3. Antimony trioxide as flame retardant4. Polybrominated flame retardantsin plastic casings, cables and circuitboards5. Selenium in circuit boards as powersupply rectifier6. Cadmium in circuit boards andsemiconductors7. Chromium in steel as corrosionprotection8. Cobalt in steel for structure andmagnetivity9. Mercury in switches and housingThe appropriate recycling of computers and IT equipment isvitally important. Several governments have taken on board themassive environmental impact of our increasingly disposablesociety, especially when new faster computers are brought tothe market and prices drop further, leading to the introductionof even faster machines.• During 2001 the Appliance Recycling Law was introduced inJapan, and the European Parliament brought in the Waste Electronicsand Electrical Equipment (WEEE) Directive, which willrequire electronics manufacturers to assume full financial orphysical responsibility for their products at the end of their consumerlife, and the Restrictions on Hazardous Substances(ROHS), which will phase out the use of some of the mosthazardous substances in the electronics industry including lead,mercury, hexavalent chromium and several types of brominatedflame retardants.• In a separate action, the European Parliament approved thephasing out of the most toxic forms of brominated flame retardants.Like the more well-known PCBs (polychlorinatedbiphenyls) brominated flame retardants threaten environmentaland human health – even in minute quantities.• There have not been any major initiatives in the US on these issues – no targeted phasing out ofproblematic chemicals, no requirements to encourage computer take-back programmes. In fact, theUS Trade Representative lobbied extensively against WEEE and ROHS.The transfer of hazardous waste is restricted by a 1989 treaty known as the Basel Convention, but theUSA has not ratified it. In fact, US officials have actively worked to defeat, and then to weaken, theBasel waste export ban.E-wasteThis loophole means that between 50% and 80% of IT wastes collected for recycling are not recycledin the US but containerised instead and sent to China, India or Pakistan. The Basel Action Network,‘Waste Not Asia’ and the Silicon Valley Toxics Coalition conducted a field investigation and founddangerous and hazardous IT waste (‘E-waste’) being dumped in fields, alongside rivers and canalsand stockpiled for local recycling. This represents a huge drift of hazardous material from rich topoor countries, where little is done to control the environmental effect. China has banned the importof E-waste yet the USA does not prevent exports. It is estimated that 90% of the E-waste exportedfrom the USA ends up in China, in Nanhai, Guangdong Province, and from there much ends up inthe Guiyu area where 100,000 people, many of them women and children, work in waste processingfor $1.50 a day. There is a thriving business of bringing bottled water into the area as the locals donot trust their drinking water source as it tastes bad.10

Most of the waste handling is done with hammers, chisels, screwdrivers and bare hands, and occasionallyan electric drill.• Copper in electrical wires is extracted by burning off the plastic coating, giving off a black noxioussmoke which could contain polyvinyl chloride (PVC) and brominated flame retardants.The emissions and ashes from such burning contain high levels of both brominated and chlorinateddioxins and furans – two of the most deadly persistent organic pollutants. It is also highly likely thatcancer-causing polycyclic aromatic hydrocarbons are also present in the emissions and ash.• CRTs have a phosphor coating which contains cadmium, zinc and vanadium and their compounds.US Navy guidelines advise seeking medical attention after contact with phosphor coatings, but mostof the CRTs that arrive in Guiyu are broken up by hand and the remnants are dumped.• Circuit boards are cleaned of metals using crude acid baths, releasing toxic chlorine and sulphurdioxide gases. The precious metals are the goal – including silver, gold, palladium and platinum.The sludge from this process is dumped and could leach into the water supply. The ground aroundthese baths was tested and found to have a pH of 0 – the highest acidity level possible.• Used toner cartridges are broken up manually and the residual toner scooped out by hand intobuckets. The International Agency for Research on Cancerhas classified carbon black (the main constituent ofblack toner) as a class 2B carcinogen, possibly carcinogenicto humans. Little information exists on the hazardsof coloured toners. Some reports indicate that such toners(cyan, yellow and magenta) contain heavy metals.The recycling of E-waste is increasing in India and Pakistan, where investigations reveal treatmentareas similar to or worse than Guiyu, some in the middle of New Delhi! The problem is escalating asLCD monitors become cheaper and more abundant, and the developed nations migrate from CRTmonitors to LCDs. To get some idea of the scale of the problem, in 2001 about 12.75 million computerunits went to recycling centres in the USA, and this is growing at 5–7% per annum. If 80%reached Asia it would be a tight stack of 820,000 sq m. Remember, this is in one year from onecountry.Leaky landfillsAll waste landfills leak. Even the best state-of-the-art landfills are not completely secure and a certainamount of chemical and metal leaching will occur. The situation is far worse for the older or lessstringently maintained dump sites. When disposed of in a landfill, E-waste becomes a conglomerationof plastic and steel casings, circuit boards, glass tubes, wires, resistors, capacitors and otherassorted parts and materials. About 70% of the heavy metals (including mercury and cadmium)found in landfills come from electronic discards. These heavy metals and other hazardous substancesfound in electronics can contaminate groundwater. In 2001, CRTs were banned from municipallandfills in California and Massachusetts because of their recognised hazardous nature.11

Incinerators are some of the largest point sources for environmental release of dioxins in the USAand Canada, and of heavy metal contamination of the atmosphere. Copper, common in E-waste, is acatalyst for dioxin formation. This is of particular concern as the incineration of brominated flameretardants and PVC leads to the generation of extremely toxic dioxins and furans, and copper makestheir formation more likely.Upstream changesEnvironmentalists have tried to exert pressure on upstream manufacturers, i.e. those making the PCcomponents and circuit boards, to change their processes to reduce the level and quantity of toxicityin their products. However, without the support of the law and government, manufacturers cannot beforced to change and will continue to supply cheaper, more hazardous components.What can be done at Bedales?We can reduce the power consumed by switching equipment off when it is not required. The ITdepartment has created a program that automatically powers down IT equipment at night in placessuch as the Hub and the IT bookable room, and this is being rolled out more widely across the wholeschool. The program doesn’t shut down a PC if a user is logged in, and the benefits outweigh anyslight inconvenience of having to power up a PC after it has been shut down. These facts mightencourage you to turn your PC off when not in use: a PC left running 24 hours a day uses £59 worthof electricity over a 12-month period and results in the emission of 716 kg of carbon dioxide a year.The school has a responsibility to encourage practical recycling, and this is carried out by using theGreen Aid paper recycling boxes. The IT department recycles used toner cartridges by participatingwith ActionAid, and we encourage consumables like toner cartridges to be used up completely, notreplaced when simply running low. We also encourage users to consider reducing the mountain ofpaper we get through each term with responsible printing.Recycling or reusing IT equipment is also strongly encouraged in the school. Older equipment isreplaced and moved to a location or user that has a lower specification requirement or use. Printersare repaired and maintained long after their warranty period has expired. Even switches and otherolder network equipment are stored and could be used to build test networks or work as a temporarystand-in for existing equipment if it fails.What can be done elsewhere?Despite the US government not participating in the schemes that we have in Europe, American citizensand some corporations are very active in the recycling area. Large IT suppliers such as Dellhave instigated schemes to recover equipment from their customers and refurbish it for resale. Ifound a refurbished Pentium P4 computer for £75 from a Doncaster-based IT recycling company.Companies in the UK such as Computer Aid International have already shipped 65,000 PCs to 101countries, and of those 45,000 went to educational establishments.For domestic users it is always worth considering anupgrade first. The longer IT equipment stays out of landfillsites the better. There are many small computer shops that provideupgrade services, and should you want to buy new anyway,why not sell the old one on eBay? I have an old SinclairZX Spectrum, which I’ve just searched eBay for, and realise Icould get £20–£30 for it! The market for used computer equipmenton eBay was around two billion dollars in 2001.Naturally any pressure that can be applied to encourage other governments to sign up to and adhereto international agreements, conventions and restrictions will improve the fate of hundreds of thou-12

sands of people directly exposed to the hazards of disposing of IT equipment. The impact of the‘recycling’ in Asia on the environment in terms of air and soil pollution is difficult to quantify butmust be significant if China has banned imports!Is IT any good for the environment?Apart from the direct physical impact that IT has on the environment and despite the relatively largeamount of natural resources required to build PCs, it is worth delving into other more positive linksbetween IT and the environment.Advances in computing technology allow us to analyse environmental data with greater speed andaccuracy. Ever more accurate geographic and meteorological models allow us to predict weatherpatterns with greater accuracy and some day might bring us one of the holy grails of scientific modelling:the earthquake predictor.Computer-aided design and manufacture provide us with the tools required to build ever moreefficient engines; and research into fuels to replace our dwindling fossil fuel reserves might not befinished before the reserves run out were it not for computers. The increase in telecommuting andInternet messaging has a direct impact by reducing vehicle emissions.Michelle Dewberry, Sir Alan Sugar’s new Apprentice, is going to mastermind Xenon Green, SirAlan’s new environmentally friendly IT recycling company. Let’s hope the company is a runawaysuccess!Justin LatterIT Department13

IJoseph Rotblatfind myself writing this on the third anniversary of the start of the conflict in Iraq and almost exactly3 years since Joseph Rotblat talked here at a Wednesday evening assembly. He died last Septemberat the great age of 96. His passing has made the world a poorer place and perhaps more dangerous.Rotblat spent the earlier part of his scientific career on research that was significant in the making ofthe first atom bomb. He spent the greater part of his life on the peaceful use of nuclear research andfighting for world peace, and urging all scientists to be aware of where their research might lead. Formore than 50 years he was Science`s standard bearer for the responsible use of all scientific research.In his autobiography Bertrand Russell wrote:"He can have few rivals in the courage and integrity and complete self-abnegation with which he hasgiven up his own career (in which, however, he still remains eminent) to devote himself to combatingthe nuclear peril as well as other, allied evils."I remember being at a lecture, a couple of years ago, listening to cosmologistMartin Rees talking about his recent book entitled `Our Final Century`. In thisbook Rees assesses the chances of the survival of the human race given all thepossible dangers that we now face, not just nuclear dangers, but chemical andbiological among others. Rees seemed not too sanguine about our sense of responsibilitybut in a wonderful vignette, in the middle of the lecture, he talkedabout Rotblat as the shining example for all of us, in his fight for the correct useof science. Rotblat felt he had to carry this responsibility as a signatory to theRussell Einstein manifesto of 1955.In a lecture at Geneva where Rotblat was receiving the prestigious Linus Pauling prize he talkedabout the duty he felt as the last survivor of the 11 who signed the manifesto. (Pauling was also asignatory.) He carried out his work under the umbrella of the Pugwash movement which he helped tofound, greatly supported by his close friend, OB Sebastian Pease. Rotblat and the Pugwash movementwere awarded the Nobel Prize for Peace in 1995.But perhaps the accolade that meant most to him was the sometime Soviet leader Mikhail Gorbachev'sstatement that Pugwash papers and conferences had helped to guide the foreign policy that hadled to the thaw in the cold war.I have written elsewhere that for me it is impossible to teach science well without seeing it in a muchwider historical and social context. As I leave Bedales, the new, much heralded, changes in the sciencesyllabus are meant to stress `how science works`. This seems to state the obvious to me and it isa sad state of affairs to have to state it in such black and white terms.Although Joseph Rotblat has now gone his work will live on. I would urge any new science teacher,indeed any science teacher, to read about his life and use him as an example of `how science works`.In his talk at Bedales Rotblat used the word `humanity` on more than one occasion. I end with aquote from his Nobel address"We appeal, as human beings to human beings. Remember your humanity and forget the rest. If youcan do so, the way lies open for a new paradise; if you cannot there lies before you the risk of universaldeath."Harry Pearson14

A Brief History of Plasticslthough today’s plastics industry is over 100A years old, mouldable ‘plastic’ materials haveexisted for centuries. Most plastics, whethernatural or synthetic, are composed of organicpolymers – materials with molecular structurescomposed of very long chains having carbon asthe backbone, which possess the ability of beingshaped under heat and pressure.Plastics are traditionally divided into two groups,thermosets and thermoplastics. The former, whenmoulded, become rigid on cooling and cannot bereheated and reshaped because an irreversiblechemical change has taken place. Thermoplasticscan be reheated and reshaped.NATURAL POLYMERSPolymers have always existed in nature and oneof the oldest in relation to the history of plastics ishorn, which can be softened and shaped into usefuldomestic items such as combs, knife handles,drinking beakers and buttons. One of the mostinteresting properties of horn is that it becomestransparent when pressed into thin sheets, andthese were used as early replacements for glass inwindows and even in lanterns, a name derivedfrom lanthorn. Another natural polymer is shellac,a beetle secretion, most familiar in the formof 78-rpm records.which was developed in the 1860s and mouldedinto decorative items, ping-pong balls andphotographic films, and cellulose acetate, a nonflammableversion of celluloid, which wasdeveloped in the 1920s. Spun into filaments, itcould replace silk, cotton and wool fibres, andcombined with a plasticisers could be mouldedinto light-coloured domestic articles. UntilWorld War II, cellulose acetate was the onlythermoplastic moulding material generallyavailable.Even casein, a natural polymer-like proteinderived from milk, was transformed into amouldable and very beautiful ‘plastic’ throughhardening in formaldehyde. Patented in 1899,casein was used to make buttons, buckles andfountain pens, and was also made into paint.THE FIRST SYNTHETIC PLASTICThe early 20th century was a period of greatchemical experimentation, and a breakthroughcame when the Belgian chemist Leo Baekelanddeveloped a completely new plastics material,phenol formaldehyde (Bakelite), shown below,In the middle of the 19th century chemists startedto mix natural polymers such as cellulose withacids, plasticisers and fillers and created mouldablesubstances known as semi-synthetics. Thetwo best known are cellulose nitrate (Celluloid),the first completely man-made plastic. It wasused first as an electrically resistant lacquer andthen, from around 1914, as a moulding materialwith countless uses. Phenol formaldehyde is athermosetting resin; it was used to make toughradio cabinets and heat-resistant cooker knobsand is usually dark in colour. Another thermosetis urea formaldehyde, which can be lightcoloured and is familiar as plugs and socketswhere heat resistance is essential. In the samefamily is melamine formaldehyde, best knownas a decorative surfacing material under tradenames such as Formica.15

Many resins are brittle and unstable on theirown, but can be transformed into useful materialsby being combined with a wide range ofadditives such as stabilisers, fire retardants andpigments, and fillers such as wood flour, micaand glass fibres. Fibre addition can greatlyimprove mechanical properties, and this is wellillustrated by plastics boat hulls and car bodypanels moulded from polyester resin reinforcedwith glass fibre. In a similar way, epoxy resinreinforced with carbon fibre produces componentswith outstanding strength which arewidely used in the aeronautics industry.RUBBERIn a category of its own is rubber, natural orsynthetic, flexible or rigid. Rubber is derivedfrom a naturally occurring polymer, latex, andhas many applications ranging from adhesivesand condoms to O-rings and tyres. Syntheticrubbers were pioneered in Germany duringWorld War II and the range of applications forrubber-like materials continues to expandthrough the development of a new family calledelastomers, plastics with rubber-like properties.PRE- AND POST-WAR PLASTICSThe textile industry was to prove a major innovatorin terms of developing new chemicalpolymers, the most notable of which was polyamidedeveloped in 1938 by Dupont in the USAand better known as Nylon. This was used asfilaments in toothbrushes and as yarn in stockingsand parachutes. When nylon mouldingpowder became available it was used for itemssuch as spectacle frames and, reinforced withglass fibre, for engineering applications such asgear wheels. In the 1930s ICI in the UK wasworking on polyethylene (usually abbreviated topolythene), and with the onset of World War IIand the need for radar insulation, research wasspeeded up using a high-pressure process. Thisproduced LDPE (low-density polyethylene),which was flexible and, like many plastics, anexcellent insulator. It quickly found a use asinsulation for electric wires and cables, whichhitherto had been the territory of rubber. In1953 Professor Karl Ziegler discovered thatpolythene could be produced at much lowerpressures by using special catalysts. The resultingmaterial was more rigid and is known asHDPE (high-density polyethylene).Mouldings made from LDPE include washingupbowls as well as films used extensively inthe packaging industry, whereas HDPE is usedto make milk bottles and sewage, water and gaspiping. Both these materials belong to the polyolefingroup of plastics, of which the thirdmember is polypropylene (PP). PP can befound in applications ranging from ropes andfishing nets to garden furniture.PVC AND MISINFORMATIONPolyvinyl chloride (PVC) was patented in Germanyin the 1930s and grew into an importantcommodity plastic owing to its insulation properties,clarity and ability to absorb plasticisers,which makes it extremely flexible. FlexiblePVC can be found in innumerable applicationsfrom leather-cloth in car interiors to most medicaltubing, blood transfusion bags and floortiles. Most electrical cables are insulated withflexible PVC. Unplasticised (rigid) PVC isused for building products such as windowframes and guttering. In recent years PVC hascome under pressure from misguided environmentalgroups due to the theoretical possibilitythat it can cause the production of dioxins whendisposed of by incineration. Extensive testswith modern incinerators have demonstratedthat this is not true. PVC is now probably oneof the best environmentally understood plasticsand its flame-retardant properties have made itfirst choice for many architectural applications.16

A PLASTIC FOR THE TOY INDUSTRYA major group of plastics is based on the simplechemical, styrene. Polystyrene tends to be brittlebut can be modified with rubbers to createimpact-resistant plastics. Examples includeHIPS (high-impact polystyrene), ABS(acrylonitrile–butadiene–styrene) and SAN(styrene–acrylonitrile). Widely used initially inthe toy industry, styrenic plastics are now employedextensively in the automotive, computerhousing and kitchen utensil industries andcontinue to find new applications.THE INDUSTRY’S PET PLASTICAlong with Nylon, another major plastic materialadopted by the textile industry is polyester.Polyester resin for casting was developed in1941 and at the same time an improved polyesteryarn made from extruded filaments was discoveredin the UK and developed by ICI underthe trade name Terylene, being produced commerciallyin the USA under trade names such asDacron and Trevira. In the 1970s an improvedpolyester found widespread application in themanufacture of bottles using the injectionstretch blow process. The name of this materialis polyethylene terephthalate, commonly knownas PET. It has clarity, sparkle, high impactstrength and excellent gas barrier properties,which make it ideal for moulding bottles forcarbonated soft drinks and mineral water. It hassince found wide application in producingcontainers for detergents and mouthwash.Other important plastics include polycarbonate,a material with very high impact resistance andtemperature stability. Typical applications arepanels for bus shelters and products that needsterilisation, such as babies’ feeding bottles, butdevelopments are now taking place in rooflights and car windscreens. The experiencegained from developing polycarbonate-coatedspectacle lenses could help alleviate the problemsof scratches. Polyacetal has been used tomake kettles and polymethyl methacrylate(Perspex), first used for aircraft canopies inWorld War II, has been moulded into car rearlights and can now be found in a wide variety ofuses such as baths and shop signs. Rigid andflexible polyurethane foams are widely usedin acoustical and padding applications, whileexpanded polystyrene conserves heat as an insulatorand protects against damage in packaging.MOULDING PROCESSESPlastics processing usually starts with feedingplastic granules through a hopper onto a rotatingscrew inside a heated cylinder, which melts thegranules as it moves the molten plastic forward.At the end of the cylinder the melt is forced intodifferent types of moulds: a slit-shaped die producesa continuous sheet, a shaped die producesa profile, an annular die extrudes rod, tube orpipe, and can even blow a vertical bubble formanufacturing thin films or a parison (a shortlength of semi-molten material) from whichbottles can be blown. These processes justdescribed are all forms of extrusion moulding.Injection moulding is a fast, mass-productionprocess whereby the screw acts as a plunger andpushes molten plastic into a closed mould.When the plastic in the mould is cool and set,the mould is opened to eject the shaped moulding.Whereas extrusion is a continuous process,injection moulding is an interrupted process.There are many other processes of which thebest known is vacuum forming, whereby a sheetof plastic is heated and softened and suckeddown into a mould. Applications include sandwichpacks and rigid packaging for toys. Rotationalmoulding is a process for moulding largehollow objects such as footballs and storagetanks, in which polymer powders or liquid plastisols,typically polyethylene and PVC, areplaced inside a closed mould and tumbledwhilst inside an oven so that the resin softensand coats the inside of the mould. Powderedplastics can also be sprayed onto wire and heatfusedto make kitchen baskets or furniture in thefluidised-bed coating process, while in anotherprocess, invented in 1956, extrusion dies areoscillated so that the flow of plastic is split intotwo and then joined up, creating Netlon mesh.A MATERIAL FOR DESIGN ENGINEERSPlastics are ideal materials for designers to workwith and can be tailored to suit each application;e.g. they can be temperature- and wear-resistant,or soft to the touch. Most unmodified polymersare clear and can therefore be pigmented tomatch any specified colour, whether transparentor opaque, and surfaces can be matt, glossy ortextured. The ability to create three-dimensionalforms with gentle curves or sharp edges allowsthe designer full imaginative reign.17

RECYCLINGThe reprocessing of plastics waste within thefactory is standard practice, but the recycling ofused domestic plastics waste is much more difficult.The variety of different plastics todaypresents many problems because plastics are allmingled in the household waste stream. To successfullyrecycle them into new products theymust be separated and cleaned – an expensiveprocess, which has delayed plastics recyclingwithout subsidies. Plastic bottles for milk, waterand fizzy drinks can be more readily separated,ground up, washed and recycled into new productsfrom car components to fleece jackets.Polystyrene parts from refrigerators are beingturned into CD boxes and seed trays. However,where plastics are contaminated or part of amixed laminated material, the alternative towasteful landfill is incineration to produceenergy. In 2004, Europe recovered over 50% ofplastics in the waste stream, converting it intonew products or energy, thereby saving millionsof tons of oil. It must be recognised, however,that recycling needs to be subsidised in order tomake it economically viable.ARE PLASTICS GREEN?The short answer is a resounding ‘yes’. Plasticproducts are light and strong and are thereforecheaper to transport, thus saving fuel. This notonly applies to the obvious advantage of plasticbottles over glass, but also to more subtle automotiveapplications such as car bumpers, lorrycabs, and bus and train panels. In addition,plastics are processed at fairly low temperatures(200–300°C), whereas glass and metals requiremuch higher temperatures, which consumesmore energy.WHAT ABOUT THE FUTURE?Plastics are finding new applications every dayand it is one of the few industries to expand byaround 5% every year. Chemists continuouslywork to improve and develop new polymers,and plastics processing techniques are becomingincreasingly sophisticated. The question oftenasked is ‘what will happen when the oil runsout?’ When Bakelite, Nylon and Formica werefirst made, coal was the chemical feedstock.Today, oil is the source for making the chemicalsneeded to synthesise plastics; however,plastics are now starting to be made fromrenewable raw materials such as sugar, starchand maize, and factories are under constructionto produce over 100,000 tons per annum. Polylacticacid is a bioplastic similar in chemicalcomposition to PET and will soon be competitivelypriced.A FINAL THOUGHTAlthough the ancestors of today’s plastics canbe traced back to antiquity, plastics are materialsof the 21st century and have become somuch part of the modern world that, if theyceased to exist, our quality of life would be seriouslydiminished. Everything that modern mandoes is either dependent on or strongly influencedby plastics. Far from being ersatz materials,as they were once considered, plastics arenow viewed as materials of choice by designersand engineers. Plastics open a world of possibilitiesfar wider than we can even imagine, andthe industry is still in its infancy.Don Cooper FPRI FIMMM(father of Andrew Cooperand grandfather of Daisy and Oscar)I am grateful to Sylvia Katz for helping to editthis history and to Sylvia Katz and ColinWilliamson for providing the photographs – D.C.Sylvia Katz (née Kemp) OB 1956–1962Urea formaldehydevacuum flaskCasein pen18

Bedales: Sustainable Buildings?ore than ever it is important for buildings to be sustainable. With fuel costs rising sharply,M heating and lighting are quickly becoming more and more expensive. Taking a look at thebigger picture, by having energy-hungry buildings you are contributing not only to instability in theMiddle East but also to global warming, probably a bigger long-term threat. It is clear that for anynew building sustainability and energy efficiency are top priorities.The new Bedales Teaching and Admin buildingdoes pretty well as far as energy efficiency goes.It is heavily insulated to reduce heat loss and thereforethe amount of energy needed to heat it. Alsoits concrete core has a high thermal mass, whichretains heat during winter and coolness duringsummer. To reduce the energy spent on lighting,the building’s large quantities of glass have beenused alongside careful design to make sure eachroom gets the maximum amount of natural lightpossible. The lights are also fitted with sensors sothat they produce only the minimum amount oflight needed. All this means that the amount of energy spent heating and lighting the new buildingis significantly less than what was spent on the old North, South and Admin blocks, which wereshockingly energy-hungry due to their almost non-existent insulation.However, our new building is missing something that all truly sustainable buildings have: microgenerators– photovoltaic cells, solar panels, small wind turbines, etc. The Bursar explained thatthe school’s reasons for this are twofold. The first is simply initial cost. The new building as it iscost £7 million, and the school couldn’t afford the additional cost of initially expensive microgenerators.He said the second reason is that the school first wants to focus on energy inefficiencyand make it as energy economical as possible. Once this has been achieved to the greatest extentpossible, we will be in a better position to start actually generating our energy on site. This has theadded advantage that, as always, technology will have improved and become cheaper as the marketbecomes more mainstream. Steps have been taken in this direction, a major one being the constructionof the new building, another being the complete assessment of the school by the CarbonTrust (see box). The conclusion of this is that about 1,500,000 kWh of energy are wasted everyyear and this comes to about £44,000 per annum. So it seems sensible enough to concentrate for awhile on trying to reduce this as much as possible.The school is still keen to look into on-site energy generation. Money permitting they would liketo make the new Art, Design and Technology building the most environmentally friendly of itskind. However, after borrowing a huge amount of money for the new buildings the school has verylittle to spare and the Governors have a 10-year plan which aims to eliminate borrowing, except forthese two big building projects, so there isn’t money for anything else. However when the moneydoes become available, photovoltaic cells could be added to most of the existing buildings, includingthe one just finished, and wind turbines could be placed in many areas around the estate.As well as energy conservation, water too is a big issue. Rainfall last winter was unusually low andin April a hosepipe ban came into effect throughout southeast England, an almost unheard of occurrenceso early in the year. The average water consumption in the south of England is 163 litres perperson per day and a third of this is used by the flushing of toilets, even though it has been treated19

and processed to drinking water standard. So itseems the responsible thing to do is for Bedales tostart thinking about water recycling schemes.Rainwater can be collected and combined withpartially treated waste water and used for theflushing of toilets and other functions wheredrinking water standard is not needed. Unfortunately,the school currently has no plans to introducesuch schemes.BedZedBedZed, short for the Beddington Zero EnergyDevelopment, is a good example of what can beachieved when you are properly committed to sustainablebuilding. It was designed by an Old Bedalian,Bill Dunster. It is the first large-scale carbon-neutralhousing development, which is onethat gets all its energy from renewable sources andtherefore does not add to the amount of carbondioxide in the atmosphere. By super-insulatingthe buildings and using heat exchangers – so thatas much as 70% of the heat from warm air leavingthe building through vents is retained by the freshair coming in – the energy needed for heating isgreatly reduced. It makes the most possible use ofnatural light, for both heating and lighting thebuildings. A combined heat and power unit whichruns off waste timber from a local tree surgerygenerates the site’s electricity. Photovoltaic cellscharge the batteries of electric cars. Water recyclingschemes supply about a fifth of the site’sneeds. Wherever possible it was also built fromnatural, renewable or recycled materials andagain wherever possible these came from within35 miles of the site, to reduce the environmentalimpact of transporting materials.BedZed and our new buildings have some thingsin common, but this development shows howmuch further we could be going.Physicists of 6-2Assessment by the Carbon TrustFunded by the government, the CarbonTrust investigates organisations and reportson ways they could lower energy consumption.It found that Bedales spends about£244,000 per year on energy, £79,00 onelectricity and £165,000 on oil and LPG forheating. Compared with standard benchmarksthe school’s electricity use was ratedgood overall but its heating was deemed tolie somewhere between typical and poor.Furthermore, Bedales has no energy monitoringprogrammes and it is estimated that£12,000 could be saved if such a programmewas introduced alongside energy managementtargets. By introducing other schemes,none with particularly high initial costs, thereport said the school could save about£44,000.It also suggested the installation of on-siteenergy generation using timber and otherforestry waste. This would involve theprocess of Short Rotation Coppicing –growing small woodlands of fast growingtrees and harvesting the timber of some ofthe trees every few years. Bedales has 120acres, and 1 acre can produce 4 tonnes ofwood fuel per year. Also, at present Bedalesburns significant amounts of forestry wastebecause of a lack of anything better to dowith it, and waste construction timber has tobe removed by contractors, at a cost. Boththese sources could also contribute fuel. Tomeet all of Bedales energy needs would requireabout 250 acres, so this alone couldnot power the whole school, but it couldprovide for a significant proportion of it.Another suggestion was the installation ofwind turbines.20

Cabo Friohe region of Cabo Frio inT Brazil is very special –ithas a dry climate - unique forthe south-eastern coast ,andcontains great lagoons andhigh dune systems which providea habitat for some unusualflora and fauna and a greatcontrast to the vast AtlanticForest which stretches alongmost of the coastline The areahas been designated as one ofonly 12 ‘Centers of VegetalDiversity’ in Brazil.The number of endemic species found in Cabo Frio is much higher than in any other restingas –sandy coastal strips – along the shore. Some areas of Cabo Frio have suffered from immense environmentalproblems in recent years though, with large areas of land being taken and used for saltmining over most of the last century and ever increasing urban expansion leading to pollution and thedumping of waste in the lagoons.With the help of Veiga de Almeida University, whose campus borders the Araruama Lagoon , thearea is being gradually restored to its natural state through a program to reintroduce native pioneerplants which have been grown in‘gardens’ at the University specificallyfor this purpose. With these plants establishedit is hoped that the land will regeneratenaturally as ecological successionoccurs and re-establish the area as a refugefor the many rare species the regioncontains as well as giving the local communityspace in which to observe thisvery unusual and fragile habitat.Given byCamila BarataBiologist and friend of Harry Pearson21

Interview with Professor Tony MarmontGood morning Professor Marmont, how are you?Good, call me Tony.For those of us who were not in your assembly can you tell us brieflywhat you do and what your aims are?I try to convince others that it is not necessary to burn fossil fuels fortheir energy and show by example that you do not need to change yourlifestyle to live without fossil fuels. I truly believe in this cause andthink it is imperative to act, otherwise we will end up killing ourselves.I’m spending my life trying to find ways and means not to release CO 2 .I’m trying to encourage individual citizens, industry and the heads ofinstitutions, like universities, to take these issues as seriously as I do.In 1992 when I realised that the situation was critical, I formed Beacon Energy with the aim ofincreasing public awareness about climate change and the things we can all do to address it. Theorganisation is a partnership of universities and business. The 120 member businesses use the developmentsof the 20 member universities. We have been able to make great progress; for example, theUniversity of Loughborough now gets all of its power from green sources.Microgeneration (the use of small-scale generation sources such as photovoltaics and wind microturbines)has been heralded by some as the solution to our ongoing energy crisis. Others think that itsimply cannot provide the necessary power and comes at too high an initial cost. Where do youstand?I believe strongly that microgeneration is the answer. Using the elements around us I think that eachhome can generate enough energy to power electrics itself, and also to store energy in the form ofhydrogen through the electrolysis of water. For example, at my home we make use of all the naturalresources around us by having wind turbines, photovoltaic cells and hydroelectric generators. Theuse of such technologies is also happening around the world. Recently during a trip to China’s ShandongUniversity I was asked to supply building specifications for an eco-friendly hall of residence.A year later when I went back, the University had built the structure to a higher specification thananything in Europe. After touring the dorms, when asked for ideas on how to improve the facility, allI could think of was putting 25 small wind turbines on the roof so that they could maximise their useof the natural resources around them.When asked, most people are surprised that the biggest consumer of energy is domestic housing. Ifmicrogeneration could be adopted by millions of homes, a massive difference would be made. It isthe simplest, easiest and cheapest way to solve our energy crisis.If microgeneration is the answer, how would you propose we start to implement it on a large scale?Next year the implementation of microgenerators is going to become easier than ever. When TVdishes are installed on homes it is assumed that the council grants planning permission for them to bethere. In autumn 2007 the same will be true for all microgenerators – so planning permission will nolonger be required, making the process of installation much more straightforward. Also, next yearanother major obstacle to generating electricity in the home is going to be removed. At the momentif you generate more energy than you are using then you need a licence to export energy back ontothe natural grid. Next year government legislation will force the local energy providers to buy backexcess energy from anyone who is generating it. This means that when you don’t need the power you’re22

generating other people can use it and you get paid for it too, making microgeneration much moreattractive. So to government is slowly moving in the right direction.To what extent do you think that hydrogen is going to be the fuel of the future?I think that it absolutely will be. I use hydrogen as part of my energy storage system at home. Oneof the problems with renewable energy is that sometimes it’s not sunny, the wind isn’t blowing andit’s not raining. This means that you have to have some sort of back-up power. Rather than relyingon the national grid I produce hydrogen, through the hydrolysis of rainwater. At times, when mygenerators are producing more energy than I can use, the excess power is used to generate hydrogen.When they are not producing enough power my fuel cells produce electricity from the stored hydrogento make up the difference. This conversion of electrical energy, which is otherwise impossible tostore, to hydrogen and then back again is 20% efficient. This sounds bad but remember wind and thesun are free. Power stations are 20% efficient too and an extra 10% is lost during transmission.Furthermore, the fuel for conventional power stations is expensive, polluting and increasingly difficultto acquire. So while this inefficiency is annoying when renewables are involved, it is actuallyvery damaging to our environment when fossil fuels are being used.Shortly I will also be using hydrogen to power my car. At the moment I have a Toyota Prius, whichis a petrol–electric hybrid. Using modified spark plugs in conjunction with a tank and deliverysystem similar to that of natural gas I’m converting my Prius to be a petrol–electric–hydrogen hybrid.So soon I will be able to use the surplus hydrogen that I produce to power my car too. I’m the firstperson to convert the Prius in this way and it will only have cost me about £1000, proving that doingthis kind of thing is possible and not too expensive. Also, to the best of my knowledge, like electriccars, cars powered on hydrogen do not have to pay road tax.Some people claim that nuclear power has a future in the generation of hydrogen. For this or forgeneral electricity production, what is your view on nuclear power?Nuclear power definitely has the potential to generate hydrogen. The power from both nuclear andconventional power stations could be used to produce hydrogen at night or during other off-peaktimes when the energy from the power stations is not needed elsewhere. Nuclear power is howevermuch better than conventional since no CO 2 is produced. But there is the little-talked-about problemthat uranium deposits will run out in 45 years. There areplans to develop the more abundant thorium as an alternativebut they are still in their infancy.Solving the energy crisis requires the source of the problemto be addressed. What are your views on energy efficiencyand the amount on energy that is wasted in the Westernworld each day?This is definitely a big issue. If you insulate a house enoughthen it does not need central heating. In Scandinavia thereare houses that require no central heating even in the dead ofwinter. They achieve this by being super-insulated: forexample, the windows are quadruple-glazed. Furthermore,when some of these houses fill up with people, they need toopen the widows when the outside temperature is –40°C. Soenormous amounts of energy can be saved by measurestaken to increase efficiency.23

Finally, what should Bedales be doing to help solve the energy crisis?Bedales could at least make a start by buying green energy from local power suppliers. This wouldmean that every time someone turns on an electrical appliance inside Bedales, they would know thatthey are not contributing to global warming.Moreover, I think Bedales should invest in a wind turbine. It could be put either out of the way orsomewhere prominent, like next to the entrance, where it could make a statement to everyone whocomes and sees the school. I think Bedales has always been a place that leads during times of newdevelopment; this is no different.The excess energy from the turbine could be sold back to the national grid or, to make an even bolderstatement, Bedales could adopt a hydrogen storage system similar to mine.The initial cost of a wind turbine would be about £1.8 million. Although this seems like a largeamount of money, the equipment I have had at my farm for 20 years has paid for itself many timesover. If Bedales wants to be a leader rather than a follower, it needs to start seriously looking intoideas like these.Interviewed byCharlie Aaronson 6-2Felix Grey 6-2If you want to ask Ashley anything aboutbees, he will be doing a question and answerpage in the next edition. E-mail your questionsto the editors!24

Global Warming?*heck out any school science textbook and you will see some version of aC story about global warming. It goes like this. Global temperatures arerising demonstrably (most estimates suggest 0.6°C in the last hundred years).This is caused in part by increased emission by human activity of the greenhousegas carbon dioxide. Yet it is very difficult to prove causality of this kind; so all that is sure isthat global temperatures have risen and carbon dioxide has risen, but how much – if any – of the formeris caused by the latter is not certain.What is in great dispute is the validity of predictions about the future. The Intergovernmental Panelon Climate Change (IPCC) models predict rises of between 1 and 6°C over the next century. But aflaw in their models is that they assume that all of the rise to date has been caused by carbon dioxide,and this is far from proven. Thus, the Kyoto Protocol type solution to this possible global problemmay be unnecessary. And it is almost certain to fail. The engine that has driven the advance in theprosperity of the industrialised nations over the last 150 years has been the availability of cheap fossilfuel, and huge countries like China and India, which have substantial indigenous coal deposits, areabout to add a vast number of coal-fired power stations to the Earth’s surface. It would seem thatsuch development is impossible to stop, so what do we do?One argument, put forward by economists starting to consider this problem and especially the likelyeconomic effects, is to look at the major consequences of warming, whatever its cause, and startplanning for, and spending money on, solving them, rather than trying to limit emissions – whichmay be an impossible, certainly hugely expensive and probably unnecessary exercise. The advantageof this, of course, is that the economic development of Third World countries is not held back.What are the major worries about the effects of warming? There are three major ones. First, sealevel rises. It is known that sea level has been rising for many decades and there is little evidence,even according to the IPCC, that it is accelerating. So global warming may be involved; but even ifit is not, measures to offset this problem would seem very sensible to take. After all, the Dutch havebeen doing this for half a millennium!Second, there is the fear that farmers will suffer problems as climates change. However, it seemsvery unlikely that farmers would continue to grow crops that are unsuitable for the new conditions,which will of course arrive slowly. The idea that they would is referred to as the ‘dumb farmer’ hypothesis,and is just not going to happen. It is unlikely that governments would need to do anythingfor the necessary adaptations to take place within agriculture.Finally, water shortages are predicted. However, world river flows are actually greater than they havebeen for a century and much water shortage is due to massive wastage. Spending money on betterwater management would, again, make much more sense than to try to control emissions which, evenif finally proved to cause significant warming, might have no effect at all on water availability.So the take-home message is this. Global warming may be happening, global warming may havesome consequences that are beginning to be seen and which have further consequences for humankind;but these consequences may only in part be the result of global warming or maybe even not atall. Best to deal with the consequences, and then we win all ways round!Gary Skinner*Based on an article by Nigel Lawson in The Spectator, 11 March 2006.Further reading:Bjørn Lomborg, The Sceptical Environmentalist, Cambridge University Press, 2001.Patrick Michaels, Meltdown: The Predictable Distortion of Global Warming by Scientists, Politicians, and theMedia, Cato Press, 2004.25

Hydrogen Fuel Cell Car(We built one because we’re so cool)ydrogen fuel cells are the ultimate in cool because they allow you to run a vehicle on renewableH energy and still be able to reach speeds of around 140 mph and 0–60 in four seconds. Even better,they don’t look really stupid like those solar-powered and piddly little electric cars that can onlymake it 50 metres down the street before collapsing, and the best thing is they don’t release any unfriendlygreenhouse gases which keeps the hippies happy. If you’re still not persuaded of howdeeply cool hydrogen fuel cell cars are, please ask yourself this question: which of these would youprefer to be behind the wheel of?(Apologies for the Jeremy Clarksonessof this, but Alistair insistedwe put it in)Anyway we bet you’re wondering how these ingenious devices work – it’s simple really (well, it’snot actually): basically it is an electrochemical energy conversion device (damn, that makes mesound intelligent and cool) and here Ashley goes into the details of it.If you want to be technical about it, a fuel cell is an electrochemicalenergy conversion device. A fuel cell converts the chemicals hydrogenand oxygen into water, and in the process produces electricity.The fuel cell relies on a very simple chemical reaction:Anode side:2H 2 → 4H + + 4e –Cathode side:O 2 + 4H + + 4e – → 2H 2 ONet reaction:2H 2 + O 2 → 2H 2 OA proton exchange membrane is a specially treated material which is a polymer that only conductspositively charged hydrogen ions, thus blocking all electrons. Water on either side of the membraneis electrolysed so that hydrogen and oxygen are created. Because the membrane is present, in orderfor the gases to react to form water, electrons from the hydrogen travel along external wires to createnecessary bonds between the hydrogen and oxygen. Now that an electron flow has been established,components (such as motors in the car) can be run. As the only emission created from this reaction iswater it can be kept in the cylinders to be electrolysed again, so the hydrogen fuel cell is not onlyclean but only a single quantity of water is needed and is never needed to be replaced.This reaction in a single fuel cell produces ~0.7 V. To get this voltage up to a reasonable level, manyseparate fuel cells must be combined to form a fuel-cell stack.Full-scale hydrogen fuel cells operate at a fairly low temperature of around 80°C, which means theywarm up quickly and don’t require expensive containment structures. Constant improvements inthe engineering and materials used in these cells have increased the power density to a level wherea device about the size of a small piece of luggage can power a car.Basically, hydrogen fuel cell cars are the next thing because they are deeply cool, eco-friendly and costhardly anything to run. So everybody’s happy: the materialists, the hippies and the capitalist scum.Just remember, you heard it from us first!Alistair Larsson and Ashley Bray Block 526

Recyclinghe battle for the Earth begins at home, in your house, kitchen and garden. Recycling food waste,T and perhaps even growing a few vegetables with vermicompost, is a small but beautiful step inthe right direction.This article first appeared in the February 2006 issue of The Ecologist [Vol. 36, No. 1]www.theecologist.org. Title: 59% and Counting. Author: George PilkingtonBiodegradable waste (BDW) from plants and animals comprises an amazing 59%of household waste. Do you simply throw yours in the bin? If so, you are sending59% of your household waste on unnecessary and increasingly lengthy journeysby truck, resulting in climate-changing carbon dioxide (CO 2 ) emissions; asthmainducingexhaust and waste dust particles; noise pollution; smell; road congestion;and increasing waste collection costs, passed on in council tax charge increases.…AND IF YOUR BDW ENDS UP IN LANDFILL…it will be costing between £8 and £17 pertonne to be landfilled, added to which there is now a landfill tax of £18 per tonne which is set tonearly double to £35 per tonne by 2010 – both charges being passed on in annual council tax rises.And once buried your BDW will produce landfill gases (LFG): LFG consists mainly of methane andCO 2 , which are both greenhouse gases. LFG also contains VOCs(volatile organic compounds) and MMOCs (non methane organic compounds),which are associated with stratospheric ozone depletion, airqualityissues (e.g. smog) and react to sunlight to form ground-levelozone. And organic acids in decomposing BDW dissolve heavy metalsin landfill sites, creating a potentially toxic cocktail of leachates that,at very small quantities, can cause serious damage to the environment,plants, soil life, water life and many other organisms.…AND IF YOUR BDW IS INCINERATED…it will be costing your council upwards of £47 pertonne, and result in fly ash that contains dioxins which are extremely toxic – particularly to infantsand unborn babies.…AND IF YOU THROW YOUR BDW INTO A KITCHEN WASTE DISPOSAL UNIT…thissimply diverts your BDW problem from landfill to a water treatment works. What’s more, it will notrecycle your cornflakes box and uses electricity in its operation; it uses one invaluable resource –water – to flush another invaluable resource – BDW – away.SO WHY NOT GARDEN COMPOST IT? Ok provided that you manage the compost properlyotherwise the food waste will build up, attracting flies and vermin. For this reason, most people donot compost their food waste.FINDING A SOLUTION TO THE BDW PROBLEM?HOW ABOUT ‘WORM COMPOSTING’?• Worm composting your BDW uses no energy.• Means fewer waste collection journeys = lower CO 2 emissions, reduced road congestion, lowerexhaust pollution, less noise pollution.• Less landfill gas = reducing climate change.• Reduced leachates = cleaner water sources and surrounding countryside.• Less incineration = fewer dioxins; less energy used to burn waste = less CO 2 emissions.27

• Less land needed for landfill sites.• Lower council tax bills – certainly lower landfill taxes and lower gate fees.• Produces the best soil in the world for plants.• Increases crop yield – why buy when you can grow?• Saves money on bagged compost and chemical fertilizers.• Less water required for watering plants.AND WHAT GOES IN?(A)All your BDW including: bread, pastry, biscuits, cereals, pasta, flour products, breakfast cereals,cakes and puddings, fruit and veg peelings, dried foods, chocolate, casseroles, stews and soups, leftoversfrom breakfast, lunch and evening meals, onions & their skins, coffee grounds, tea & tea bags,AND cardboard – from egg boxes to loo rolls, cotton, wool, old clothes, grass cuttings dead flowersand tree leaves, wood sawdust and shavings, newspaper and a lot more besides!BETWEEN ENTRY AND EXIT: A NATURAL MIRACLE TAKES PLACE(B)As up to 59% of your household waste or BDW passes through the worms’ guts,microbe numbers increase massively. And these microbes are of paramount importancein the recycling of nutrients in the soil, such as nitrogen, sulphur, phosphorusand trace elements. It is only through the actions of soil microbes that nutrients inorganic matter are broken down and returned to the soil, liberated from plants and foruse by other microbes, Life on Earth depends on this process, and a single gram ofhealthy fertile soil contains upwards of a million microbes. And it is these microbesmassively increasing in the guts of the worms that speed up the decomposition of the BDW,which takes a very long time without it. Quite simply: no BDW, no microbes – no microbes, noworms. None of either, no living soil. In essence, the worms and the BDW they are feeding on areperforming a natural miracle – transforming expensive polluting waste into living soil.END PRODUCT = VERMICOMPOST(C)Vermicompost is a fine textured, dark peat-like material with excellent structure, porosity, aeration,drainage and moisture-holding capacity that has a similar appearance and many of the characteristicsof peat (without having to destroy peat bogs to obtain it).Increase in plant yields: Research data shows that vermicompost has increasedyields of lettuce by 14%, broccoli by 40%, tomatoes by 80% and carrots by 259%.Contains natural plant stimulants: Vermicompost contains natural plant stimulants/hormones such as auxins, which promote root formation and bud growth.Helps fight plant diseases: The high concentrations of humus in vermicompost helpto prevent harmful plant pathogens, fungi, nematodes and bacteria. Vermicompost also suppressesdiseases such as club toot and white rot.Encourages rapid seed germination: Research has shown that cauliflower seed emergence was uniformlyearlier, with hardier and bigger seedlings that were ready to plant out up to two weeks earlierand more resistant to downy mildew.Best imaginable potting soil for greenhouses: Being a natural product, it does not burn plants ortheir roots, or even the most delicate of flowers. And having water-soluble nutrients, the benefits areimmediately released to plants after watering as they slowly leach down to the roots.Increases mycorrhizal fungi activity: In several crops vermicompost was shown to increase the28

uptake of vesticular arbuscular mycorrhizal fungi, which live in the soil and form mutually beneficialrelationships with plants.Produces and promotes a healthy root mass: Trials clearly showed a fourfoldincrease in root mass, length, girth and secondary development whengrown in vermicompost. The plants also established more quickly with sucha strong healthy root structure.Improves soil structure: Vermicompost contains a high percentage ofhumus, which helps soil particles bind together into clusters, creating channelsfor the passage of water and air. Worms also produce mucus and this is deposited in the vermicompost,again giving it a friable and crumbly structure. This translates into much less watering asvermicompost remains moist for longer, and is capable of holding two to three times its own weightin water.Produces a liquid ‘golden soil’ – vermi tea: A brew of vermi tea, made from fresh vermicompoststeeped in water for a short period, is full of nutrients and beneficial microbes, and has been found tobring natural fungal disease-suppressant qualities when sprayed onto the leaves of plants.Paul Farley (Technology Department)Block 3 Pond Dipping29

The Science of the Sune know very little about the Sun although it provides our heat and light and drives mostW mechanisms on Earth from the weather to our food chain, and most of what we know is onlytheory. The theories we have used are modelledon similar things on Earth where they can be, sothey could be wrong, and for other processes wehave nothing to model them on.One thing we are certain of is the composition ofthe Sun: through absorption spectra we can tellthat its surface is made up of 71.0% (by mass)hydrogen, 27.1% helium and 0.97% oxygen, aswell as about eight other detectable elements. TheSun has seven different layers, like the geographicalmodel of the Earth: inner core, outer core,mantle and crust, but different.The core of the Sun has a density ten times that of lead – which rationally would mean that it is solid,but because it has a temperature of 15 million degrees Kelvin (K) (add 273 for degrees Celsius) thecore of the Sun is a gas. Because of this intense heat and the high density, fusion reactions take placereadily (two heavy hydrogen atoms making a helium atom), producing gamma rays (the most energeticform of radiation) and neutrinos which are notoriously difficult to detect; because of absorbanceand re-emittance, the one high-energy gamma ray leaves the Sun as 1000 low-energy photons (smallpackets of light).The next layer is the solar envelope, made up of the radiative and convective envelopes whichtogether make up 60% of the mass and 90% of the volume of the Sun. Its temperature is 4 million K.The cooler a gas is the less efficient it is at transferring energy via radiation, so it starts forming convectioncells. Hence the convective envelope, which is made up of layers of convection cells withthe smallest ones (but still about the size of the Earth) nearest the surface, and the separation in thesolar envelope.The light that we see from the Sun is from the photosphere; this is a comparatively thin layer, only acouple of hundred kilometres thick, of a much lower temperature (6000 K). At this point it has takena single photon of light 30,000 years to come from the core to the surface because of interactions onthe way (it cannot move 1 cm before hitting an atom and changing direction, even though at thespeed of light (c) it would take it 2.3 seconds to complete the journey).Even though the photosphere is technically the surface of the Sun, there are two more layers: thechromosphere and the corona. The chromosphere is red due to an abundance of hydrogen and is at7000 K (first mystery; nobody yet knows why, there are theories but none have been proved) whichis hotter than the photosphere, but even more surprising the corona has an average temperature of1 million K but can reach 3 million K in places. The corona is visible only during eclipses and is alow-density cloud of plasma (simply, a plasma is a gas where all electrons have been ripped offatoms so it is fully ionised); it is white but not as bright and many times larger than rest of the Sun.The Sun has a magnetic field much like the Earth’s magnetic field but about 100 times stronger; thisis distorted by the rotation of the Sun, which interestingly is 34.4 days at the top and bottom but 25.1days in the middle because the Sun is not a sphere but elliptical and a gaseous body. This distortionof the magnetic field causes sunspots and solar flares which I will explain later. The magnetic fieldflips like the Earth’s: the Sun’s magnetic field flips every 11 years (the Earth’s switch interval ismillions of years) and is followed directly by changes in sunspot activity, so I am going to have toexplain what they are.30

Sunspots are areas where the magnetic field of the Sun gets twisted and anarea of high flux density occurs (effectively a concentrated localised magneticfield) that protrudes though the Sun’s surface; this causes the area tocool, which is why it looks black because the area surrounding it is muchhotter. These magnetic protrusions cause solar flares – surges of magneticenergy released suddenly when a twist of magnetic field crosses itself. Asanyone who has been taught about magnets knows, field lines don’t cross;however, they don’t break either and magnetic reconnection occurs to amore energetically favourable situation, causing radiation that crosses theentirety of the electromagnetic spectrum so we can see it. The energyreleased by this is about equivalent to millions of 100-megaton (100 million ton) hydrogen bombs.That’s really big: 1,000,000,000,000,000,000 calories big! To put it in perspective a Mars Bar has230 calories in it. As these flares are one of the few things that can extend into the corona and areabout 20 million K, they could be what keeps the corona as hot as it is.Another possibility for this is coronal mass ejections (CMEs).A CME is a huge burst of plasma that releases a huge amount of material.In my research for this article I could find no references giving a reasonwhy CMEs happen, apart from the fact they coincide with a large solarflare some of the time. The shape of the CME follows that of the magneticfield. Unlike solar flares, which can be pre-empted although notquite predicted, CMEs cannot be predicted as yet. They can only be seenby placing a disc over the Sun (as shown left) because the Sun is sobright, which also explains why they were not seen until the Space Agestarted. A few years ago a very infrequent event occurred: a CME came directly at us, there werestunning Northern Lights but telecommunications were severely disrupted, the Earth’s atmospherewas in danger of being blown away and a large number of satellites had to be shut down when wesaw it coming because their circuits would have been fried by the high-energy particles. Happily thishappens only very rarely and our magnetic field protects us. There is, however, a constant lowerenergystream of particles which fall down gaps in the Earth’s magnetic field and heat up in theatmosphere causing the aurora; this stream of particles is called the solar wind and without it ourmagnetic field would have prevented any life forming on this planet.We have very few satellites watching the Sun; the main one is the Solar and Heliospheric Observatory(SOHO) which is now in its 11th year. This is placed at the first of five points around our planetwhere a satellite can orbit about a point of empty space due to cancellation of forces and gravitationalpotential, these are called Lagrange points.————————————————————————————————————————Thank you to Dr Lucie Green at Mullard Space Science Laboratory, University College London, forinspiring me to write this article.Appendices and further reading: www-solar.mcs.st-and.ac.uk/~lorna/WORK/moves, wwwastronomy.mps.ohio-state.edu/~dhw/Intro/lec7,www.astro.umd.edu/~miller/Gallery/sun/cme.gif,science.nasa.gov/headlines/y2000/ast13sep_1, science.msfc.nasa.gov/ssl/pad/solar/cmes, hyperphysics.phy-astr.gsu.edu/hbase/solar/sunspot,www.cnn.com/TECH/space/9903/09/coronal.ejections,www.nasa.gov/vision/universe/solarsystem/flare_sept7, www-solar.mcs.st-and.ac.uk/~lorna/WORK/moves, spaceweather.com/images2001/24sep01/cme_c3_big.gif, www.physics.montana.edu/faculty/cornish/lagrange, fusedweb.pppl.gov/CPEP/Chart_Pages/5.Plasmas/SunLayers, hesperia.gsfc.nasa.gov/sftheory/flare,hyperphysics.phy-astr.gsu.edu/hbase/solar/sun, science.msfc.nasa.gov/ssl/pad/solar/the_keyAlistair Barrie 6-231

The 6–1 Physics Trip to Thorpe Parkn the Spring term 06 the brave members of 6–1 Physics undertook an experiment to measure theI deforming and accelerating forces acting on the human body under the extreme conditions ofbeing dropped, rolled, fired, spun and swung on the evil-sounding adventure rides at Thorpe AdventurePark in Surrey.The experiment involved continuous data loggingof the acceleration experienced during the ridesby strapping up with electronic accelerometersand data storage devices, then matching thesedata to video footage, pictures and informationabout the dimensions of the rides.Some of the data recording resulted in unforeseendifficulties. We had on occasions to smuggle thelogging equipment on board at the risk of beingmistaken for terrorists, some of the video footagefrom the rider’s perspective suffers from whatmight euphemistically be called camera shakeand for general consumption some of the audiorecordings would certainly have to be beeped out.Science often requires working under extremeconditions and it took some motivation as wedrove through cold wind and rain to arrive at the park. This kept the queues short and some greatdata were collected. Favourite rides included ‘Nemesis Inferno’.Acceleration—time graph for PaulTaylor on ‘Nemesis Inferno’The ride’s claim of taking the rider throughchanges of –1g to 4.5g seems to be well supportedby these data.32

Olivia Hills gets a soaking (again)Unfortunately ‘Stealth’, the new ride that claims to acceleratefrom 0 to 80 km/h in 2.5 seconds and reaches aheight of 70 m, was not operating on the day.Tobias Hardy33

Stem Cell Researchlthough medicine is now able to cure disease, alleviate suffering and saveA lives, people are still dying from illnesses that have inflicted humanity forcenturies. Stem cells though are heralded as being able to do what was previouslythought impossible: they can reverse diseases and can be used to regenerateorgans for people in need. But there is still a great deal of controversyabout them with debate happening all over the world and different countriestaking different positions.At the point of conception, human life is a single cell which amazingly holds the potential for everythingto come. This cell divides and divides, turning first into an embryo, then a foetus and finally achild. The first hundred cells in an embryo are the stem cells, which are the key to this research. Theyare pluripotent, meaning that they have the ability to becomeany type of human cell, from liver cell to muscle cell to neuron.In stem cell research these cells would be removed fromthe embryo five days after conception and inserted into apatient. Because of their pluripotency, the injected cells wouldregenerate within the body and so repair any organ that hadbeen damaged. A perfect example of this is the extremelypainful disease cystic fibrosis (CF), in which the lungs aredamaged due to the fact that the mucus being produced is tooheavy and cannot be brought up by the cilia in the throat. Byinjecting stem cells into a CF patient, all of the sufferingwould end as the lungs would begin to work properly and thedisease would become merely chronic, if not cured completely.This would provide a real chance for people sufferingfrom diseases like cancer, CF and Parkinson’s to return to thetype of life that they, as human beings, deserve to live.The problem with this process is that in removing the cellsthe embryo is killed. Some people believe that human lifeexists from the moment of conception and so the removal ofstem cells would constitute murder and therefore be morallywrong. On the other hand, in vitro fertilisation (IVF) oftenresults in an excess of fertilised eggs which are simplydisposed of. The stem cells from these eggs could theoreticallybe used to save many peoples’ lives and remove theenormous pain that they live with. But some people stillhave a problem with the use of stem cells even when arisingfrom IVF because they believe it is tantamount to an exploitationof both the parents and the life involved.Obviously, it is difficult to pinpoint the moment that a clusterof cells becomes a life, but in my mind a hundred cells simplyhold the potential to become life. We destroy many more thana hundred cells when we cut our finger but have no ethicalqualms about it. I also believe that humanity has a moral responsibilityto alleviate pain and anguish where possible, andthe use of stem cells would certainly do this. Therefore I believethat the research and use of stem cells is not only acceptablebut morally the right thing to do.Honor Eldridge 6–234

The Technological Advancement ofMechanical Aids in Runningue to better drugs testing over the years, the possibilities of beingD detected have increased and athletes found guilty are faced with alife ban; therefore athletes and coaches are always looking for legalways to improve performance. The various ways by which performance can be improved are knownas ergogenic aids. At the highest professional level, sport is a highly competitive occupation withmillions of dollars depending upon fractions of a second or tenths of a centimetre. However, even thededicated amateur is willing to invest a great deal of money to improve his or her performance. Inthis article I look at Adidas Running Shoes, their advancement and how effective they are when itcomes to improving performance.To understand how running shoes help, you have to understand the mechanics of the foot. The bigtoe is the end of the most important pivot of the foot and, together with the ankle, gives an excellentmechanical advantage to propel the weight-bearing foot through space, which takes care of sprinting.The first metatarsophalangeal joint also offers lateral stability to the foot. The key to the foot’s secretis the ability to lock and unlock the forefoot against the rear foot. Simply moving the heel from sideto side does this. External turning of the heel unlocks the forefoot and causes the extremity tobecome a mobile adaptor. This is useful when contacting the ground. Internal rotation of the heelcauses the foot to lock, giving a rigid lever to propel the foot forward. Feet form the foundation ofmost sports, whether acting as hydrodynamic rudders in swimming or as springs and levers that propeltrack and field athletes. The real success of feet is in their arch construction. We are all familiarwith the medial arch but there is also one on the outside of the foot and an anterior arch, across theball of the foot. Feet respond constantly to changes in the strength and direction of downward forcesas we move, as well as to the upward reactions from ground contact.Repetitive activities require unusual muscle strength, but provided the feet are protected in appropriatefootwear and the athlete is toned to perfection, then stress-related injuries are minimised. Sprintersand jumpers need rigidity and may be further advantaged by equinus feet (horse-like) with theforefoot sitting lower than the heel. In this way the physical make-up of an athlete determines thekind of sport they have a natural aptitude for. Competition shoes should not obstruct the natural abilityof feet to move. The function of sports shoes has much to do with protecting the body fromtrauma and pathological compensations brought about by persistent and extreme activities.After the mechanics of the foot we need to understand the ‘anatomy’ of the sports shoe. According torespected US podiatrists and sports injury specialists, athletes ‘should consider the following featureswhen choosing a sports shoe, a lightweight shoe type and style appropriate to activities. Improvementsin lasting and construction techniques have more or less guaranteed comfort and support, so nowearing in of the shoe, is required. Shoes have to offer the right heel pitch and toe spring for efficientpropulsion and the materials and durometer of rear foot/forefoot midsole and components need to beappropriate in stiffness and thickness for extreme use’. Heels require supporting, protecting andstabilising throughout stance phase. Outsoles should provide proper grip for playing surfaces, withlacing systems appropriate to comfort and serviceability. Quite a list, but for a good reason and asalways conditions apply to individual needs.Human movement in most sports that involve locomotion depends on the ‘gait cycle’: a repetitivecycle of events which involves stance phase and swing. During stance phase the heel hits the groundfirst and then, as the foot adjusts to the ground surface, the centre of mass passes over the pedestal asweight transfers from one leg to the other. Swing phase completes the cycle when the weight-bearinglimb propels through space to return to stance phase again. The gait cycle consists of one stancephase and one swing phase, and in normal walking would take approximately one second to complete.Stance phase consists of 60% of the cycle. This subtle movement is hardly visible but essentialto reduce damaging forces, which pass upwards through the leg to vulnerable weight-bearing joints.35

The potential for technological advancement of footwear is phenomenal; for example, in the 2004marathon, runners wore microchips tied to the laces of their shoes and every five miles the runnerspassed an antenna that recorded their distance and speed. However, the inclusion of micro technologyinto footwear has had limited success to date even though some sports shoes have had novelty lightsand timepieces fitted. Of all the items of clothing, the shoe presents a logical focus of wearable technology.According to experts, unlike articles of clothing that must be washed or cleaned, shoespresent a more stable place to add useful electronics.The German-based company Adidas has released a prototype sportsshoe with microchip technology, which continuously reconfiguresits sole to provide a constant level of support while the wearer isrunning. The heel contains a sensor and magnet to gauge the cushioningneeded, relays the data to a microprocessor and a drive trainrunning from the motor makes adjustments. Every second, thesensor in the heel takes up to 20,000 readings and the embeddedelectronic brain makes 10,000 calculations, directing a tiny electricmotor to change the shoe.The relationship between the action (A)/reaction (R) force, thenormal (N) force and the friction (F) force (K.E. Easterling)The heel sensor measures the density in the heel with each step. The shoe runs on a 20 MHz processorand makes 10,000 calculations a second. Two buttons on the side of the shoe let runners indicatetheir preferred amount of ‘squish’. The watch-type battery will last 100 hours or up to 600 miles –roughly the life of the 14.1 oz sneaker.The optimum design of a sports shoe requires the application of a number of disciplines, not only forenhanced performance but also to make the equipment as user-friendly as possible from the positionof injury evasion. Clearly, this design includes inputs from materials science, mechanical engineeringand physics; however, it also requires knowledge of anatomy, physiology and biomechanics.The analysis of forces and stresses that act on thebody in various sportsRunning shoes make a difference. Milliseconds make a difference. As Ciro Fusco, senior researcherfor Adidas, emphasises, there’s no such thing as ‘magic shoes’. No footwear can help an athlete performbetter than his potential. The goal is to minimise inefficiencies that detract from a ten-tenthsperformance.Adidas sponsors Ato Boldon, one of the best sprinters in the world.36

Running shoe theory is an evolving science with different concepts falling in and out offavour at any time. One of Adidas’s competitors, for example, built its shoes on the principleof energy return or spring. Stepping down transfers energy into the shoe, and thatenergy comes back to help the runner lift. Fusco countered this argument, saying energy return doesnot work, except maybe on a trampoline. The average running stride is of the order of 12 milliseconds,so even if you have a shoe with spring, he says, by the time the shoe can return the energy yourfoot is already in the air.Adidas’s approach to footwear and other sports gear is one of energy maintenance. In track and fieldevents, the foot can be viewed as a lever that is pushing an athlete forward while he’s running. Thismeans that when a foot flexes, energy is lost. Minimising flex in footwear is one way to minimiseenergy dissipation. Fusco came up with this energy maintenance concept when Adidas asked him toconduct research into Olympic gear after the 1996 Games. When he started the project, Fusco studiedhow animals that run evolved. Their heels don’t touch the ground anymore, Fusco found, so theiranatomy apparently had been modified. Such animals stand on their toes and have very stiff metatarsaljoints.The Adidas research team also worked with the University of Calgary. A student, who is now a professor,was studying energy dissipation and energy return at the joints. Looking at the ankle, kneeand hip joints in a person who was jumping, he found that energy is absorbed when there is contractionof the joint. Energy is returned when the joint extends. During the milliseconds that this occurs,a small amount of energy is lost due to internal dissipation. But when the student looked at the metatarsaljoint, he noticed something interesting. Energy was only being absorbed, or lost. There was noenergy return. He theorised that perhaps it was not necessary to bend the foot during certain athleticmovements such as running. The student brought his findings to Fusco and talked about stiffeningthe metatarsal joint to eliminate the dissipation of energy at that joint. The idea seemed to fit Fusco’scomparative anatomy work and how to make a human foot run more like that of an animal’s. Thesolution was a full-length, full-width shoe plate, eventually called the Performance Plate by Adidas,which has the right stiffness and flexibility so it doesn’t impair movement. With the plate, the jointisn’t stiffened completely. The right balance of flex and stiffness, needed to minimise energy dissipationat the metatarsal joint, came only after tests with athletes.Running shoe spikes basically haven’t changed in years, with the exception of using a lighter-weightceramic–aluminium material. Fusco and his team looked to see if their energy maintenance philosophyalso could be applied here to pick up a millisecond or two. The Olympic track surface is calledMondo, after the Italian company that manufactures it. Rubber-like strips are applied to a cementfoundation and the result is a uniform surface with good traction. The friction of conventional metalspikes puncturing the surface and being pulled out was a source of energy dissipation. Thereforethere was room for improvement. Mondo supplied Adidas with specs on all mechanical characteristicsof the track. The data were used for finite element analysis and extensive mathematical modellingto come up with the answer; saving a lot of money by working with computers (which eat lessthan athletes), the Adidas team developed the Z-Spike, so-called because of its Z-shaped crosssection.Unlike conventional spikes, the Z-Spike does not penetrate the track for traction – it deformsit. The acid test was conducted with athletes. According to Adidas, the beauty of the Z-Spike is thatonly three spikes installed on a shoe give the traction equivalent to a full set of seven to eight conventionalspikes. When athletes laced up the shoes with the Z-Spikes without knowing what was on thebusiness end of the shoe, Adidas said they later “couldn’t believe they were running with only threespikes on the surface”.The benefits of Adidas’s Olympic running shoe technology will be filtering down to the general consumer.Adidas, in the meantime, is already pursuing the next breakthrough in running shoe technology,whatever that may be. Yet it is known that the best way to pick out a top track medallist is justby watching his feet. You should simply look for the runner with the golden arches.37Lucienne Harrington 6-2

How Aspirin Worksrostaglandins are chemicals which make nerve endings in tissue register pain more than usual.P They are produced in large amounts at sites of tissue damage. They are produced from the fattyacid arachidonic acid in a pathway that involves the membrane-bound enzyme prostaglandin Hsynthase (PGHS), also known as cyclooxygenase or COX (see Figure 1 and Figure 2).Figure 1 – Prostaglandin synthesisFigure 2 – Prostaglandin synthesisPGHS produces prostaglandins that cause fever andinflammation. Arachidonic acid from the endoplasmicreticulum and internal cell membrane moves through thechannel to the core of the enzyme, where it is convertedinto prostaglandin H 2 .Aspirin is a molecule made from salicylic acid and an acetyl group.When aspirin enters the interior channel of the PGHS enzyme itsplits into two, with the acetyl group binding to a site inside thechannel and the salicylic acid usually floating away.Figure 3 – Prostaglandin synthesisFigure 4 – Prostaglandin synthesisThis results in a new enzyme configuration. The acetyl group is boundto a site called serine 530 which blocks arachidonic acid from the coreof the enzyme, thus preventing its conversion to prostaglandin H 2 .Aspirin also shuts down all isoforms of the PGHS enzyme (COX-1 andCOX-2).Zoe Riddell 6–238

.TA Note on the History of Mathematical Models ofPopulation Growthhe application of mathematics in biology stems from three main areas of interest: populationgrowth, the spread of epidemics and population genetics. The first two are closely related. Thework in genetics centred upon the research of Galton and Pearson. The mathematical theory of populationgrowth developed with both discrete and dynamic models. Data collected on actual populationsalso provided much of the impetus for the development of statistics, as seen in the work of KarlPearson and Adolphe Quetelet. The work was initially concerned with the human population andthe populations of single species in general.From the mid-1740s in England there was an increase in demographic and economic growth. The1730 population of about 5.3 million was little changed from the 1650 population but increased to5.8 million by 1752. Mortality from epidemic diseases declined in this period, although typhus,dysentery, measles and influenza took their toll. On the whole, better nutrition and improved civicfacilities such as sewers and piped water helped, although the new towns lacked hospitals and mostcivic amenities. The very successful mass inoculation against smallpox may have improved malefertility as well as saving lives directly. In industrial areas people were marrying younger and havinglarger families. In the last quarter of the 18th century the population began to soar with the censusreturns of 1801 and 1811 showing an increase in population from 9.2 million to 10.5 million [1,2].With increased wealth, more funds were available for investment and there was much interest inannuities, which led to the accurate construction of life and annuity tables. A life table lists the numberof people likely to be alive each year out of an initial population (ten thousand or a hundred thousand,say). They are constructed for male and female lives separately and are drawn from all representativegroups of the population. In Holland, de Wit published the Report to the States of Holland(1671) and tables of annuities followed. In England, the mathematician and astronomer EdmundHalley [3] published a mortality table entitled An estimate of the degrees of mortality of mankind(1693). He constructed life tables from the bills of mortality of the German city of Breslau and thencalculated from that table the annuity rate on one, two and three lives. The method he used is essentiallythat used by actuaries today.The Swiss mathematician Daniel Bernoulli undertook the first serious mathematical study of mortalitycaused by smallpox [4], probably the first attempt to model the propagation of an infectiousdisease. Although not concerned with population growth, many of the arguments are similar. Likemost assumptions made in mathematical modelling they did not exactly match the natural picture, butthey were in close enough agreement with the experience. Bernoulli constructed the differentialequation:d x mn= ,dqmq−1whereq = ratio of the population who had not had smallpox to the number of survivors, at age x years;1/n = the probability of contracting smallpox;1/m = the probability of dying if contracted.In 1798 Thomas Malthus published anonymously An Essay on the Principle of Population (The FirstEssay) [5], in which he expressed concern that the population was growing at an exponential rate butthe food supply only as an arithmetic progression. Despite the fact that Malthus had studied mathematicsat Cambridge, he made no attempt at a dynamic model. The model proposed by Malthus was39

effectively a single species model with the rate of change of population being proportional to thepopulation at that instant. Thus the rate of change of population at time t is given byd N= rN ⇒ Nn() t = N (0)e,d twhere the constant r, the coefficient of growth, depends upon the number of births and deaths.Hence the population grows at an exponential rate. Such a situation is unreal for most species, withmany factors affecting growth. The human population, however, demonstrates such a growth overthe past three hundred years.Adolphe Quetelet is regarded as one of the founders of statistics. He understood the national importanceof demography and, in 1826, published data on mortality rates in Brussels, dividing them intogroups by age and sex. He influenced Verhulst, who in 1836 proposed a self-limiting process forpopulations growing large, as opposed to the Malthusian model. Quetelet proposed that he shouldconsider a quantity opposing population growth, rather like friction opposing motion. He proposed acarrying capacity, k, such thatd Nd t⎛ N ⎞= rN ⎜ 1 − ⎟ ,⎝ k ⎠where N is the population at time t and r is a positive constant. Verhulst used the term logistique inhis 1845 paper [6] and the term ‘logistic curve’ is associated with Verhulst’s work. The logisticcurve would be used to read off populations at specified times. The solution to the differential equationabove is known as the logistic equation. Much debate followed as to whether this could beregarded as a law of nature. Verhulst himself remained realistic, realising that the model dependedentirely upon the choice of function as ‘resistance to growth’. The general acceptance of the logisticequation in the early part of the 20th century owes much to the almost crusading enthusiasm of RaymondPearl. He was the main protagonist in the United States, where the equation evolved independently.Pearl and Reed introduced the same curve in 1920, following on from the work of Robertson,a physiologist. Like Verhulst, Pearl realised that something beyond a quantitative resemblance wasnecessary to establish the equation as a law. The validity of the logistic equation as a law dependedon its accuracy in predicting the known data on population levels. They predicted a limiting figure of197 million as the population of the USA and gave the point of inflection of the curve to the exactday (1 April 1914). They were less than successful when applying the logistic curve to the populationsof other nations. Pearl was joined by Lotka, who proposed models of the type dN/dt = aN + bN 2 .Unlike Pearl, Lotka realised the limits of the logistic equation as a law of nature.One of the main contributors to the mathematical theory of population growth was the Italian mathematicianVolterra. His background was quite different from the biological and statistical fields ofVerhulst and Pearl. Schooled in the analysis of Dini and the mathematical physics of Betti, Volterrabrought a different approach to the problem. In 1925 Volterra began to consider the variations in twopopulations inhabiting the same environment [7]. He became interested in the problem when askedto provide a mathematical explanation for the varying fish populations in the Adriatic during the FirstWorld War.Volterra considered predator–prey models. He considered populations N 1 and N 2 , in which the firstdoubles in time t 1 and the second halves in time t 2 . He then supposed that the populations inhabit thesame environment and that the first population preys on the second population. He formed thegrowth rates of the two populations asdNdtdN= ( a − b N ) N and = ( − a + b N ) N ,dt1 21 2 2 1 2 2 1 240

where a 1 and a 2 are concerned with growth (and may not be constant) and b 1 and b 2 are constants.Volterra solved the equations which yield a closed curve as shown in Figure 1.If T is the time for a complete cycle with populations returning to their original values, the period isgiven approximately by2πT = = 9.06 t1t2,aa1 2t 1 and t 2 being the times for the populations to double and halve, respectively.Volterra deduced three laws:1. the fluctuations of the species are periodic;2. the means of the populations are independent of theinitial conditions as long as the different coefficientsremain the same;3. if external factors reduce populations, the meannumber of the prey population grows whilst the meanof the predator population decreases.The third law showed good agreement with statistics gatheredfrom fish markets in Trieste, Venice and Fiumebetween 1910 and 1923 [8] (Figure 2).Figure 1Figure 2Continuous models do not take into account mating frequency, gestation periods and seasonal effects.It is therefore desirable to build some delaying factors into the equation.Differential equations do not take into account changes to a system over a period of time. Systemsthat do are called non-linear systems and include areas such as chaos, catastrophe and fractals. Morerecently, non-linear methods have been applied to population models.41

References and notes:[1] Roy Porter, English Society in the Eighteenth Century, Penguin, 1982 edition.[2] J.H. Plumb, England in the Eighteenth Century, Pelican, 1963 edition.[3] Geoffrey Heywood, Edmund Halley, astronomer and actuary, Journal of the Institute ofActuaries 1985, Vol. 112, pp. 279–301.[4] D. Bernoulli, Essai d’une nouvelle analyse de la mortalite cause par la verolee des avantages del’inoculation poue le prevenir, Memoires de Mathematique et Physique, Paris, 1760.[5] Thomas Mathus, An Essay on the Principle of Population, Penguin Classics, 1970 edition [firstpublished 1798].[6] P.F. Verhulst, Notice sur le loi que la population suit dans son acroissement, CorrespondanceMathematique et Physique, 1838, Vol. 10, pp. 113–121.[7] V. Voltera, Una teoria matematica sulla lotta per l’esistenza, Scienza, 1927, Vol. XLI,pp. 85–102.[8] Mainly selac (Acanthus vulgaris, Scyllium sp., Mustellus sp., Squatina angelus, Trygon sp.,Myliobatis sp., Raja sp.).Philip Robinson (Maths Department)The Death Penaltyne of the most controversial issues in the press at the moment is the death penalty. The factO that America is the only country other than Somalia to execute under eighteens has provokedmore than a little debate and every time a high-profile case comes up, the public becomes obsessed.But with the help of a Californian Appeals Court Judge and the 8th Amendment, which bans ‘crueland unusual punishments’, the death penalty’s days may be numbered.After reading a report, Judge Fogel ruled against the use of the current concoction. The report, publishedin England last April, states that the lethal three-drug cocktail does not deliver a ‘painless,swift and humane’ death and may actually be an excruciating way to die. The injection containsbarbiturates and two different types of sedatives, which theoretically anaesthetise the criminalbefore the barbiturates take effect. If injected into the left arm, which is closest to the heart, it takeseleven minutes for death to occur. The researchers, though, stated that the sedatives are in fact simplymasking the effects of potassium chloride as they paralyse the prisoner, leaving him ‘unable tomove or breathe’ or even express the pain that he is suffering. This would suggest that the fulleffect of the barbiturate would be felt, which would include ‘suffocation, excruciating burning painsand agonising muscle cramps’.In light of this information Judge Fogel ruled against the use of the sedatives but has stated thatanother barbiturate, sodium thiopental, can be used. Unfortunately, despite only needing five gramsof the chemical, it would lengthen the process to forty-five minutes and also be an extremely painfulprocess. Because of the pain involved, doctors are therefore able to refuse administering theinjection and possibly could face being struck off the register for not complying. Therefore, thenumber of capital punishment deaths will decrease in the next few months due to medical moralityencroaching upon the American criminal justice system. Having said this, using human lives toillustrate policy is amoral and wrong regardless of intentions.Honor Eldridge 6–242

B-Sci Photograph Quizelow are two photographs – A and B. The quiz has three questions.B1. What are the scientific names given to the natural features they depict?2. How are the two photographs related?3. What is the name of the science which studies these and other landform features?Photograph APhotograph BAnswers to Colin Prowse (hog@bedales.org.uk).The editors of B-Sci have agreed to award a suitableprize for the best answers and print them inthe next edition. Correct answer given in the nextedition.43

The B-Sci CrosswordAcross1. The process of naturally wearing down or weathering (7)3. An Australian marsupial (5)6. A shape of bacteria (7)8. A material one of the three little pigs built their house from (5)9. The destruction of our forests (13)14. Keep company with (7)17. An infection that got into action man? (13)19. Second part of the small intestine (5)20. What this magazine is about (7)22. A silky type of fabric (4)23. A place of scholarship and learning (7)Down1. The tide _______ and flowed (5)2. A wise bird (3)4. Not alkaline (7)5. Unsaturated hydrocarbons (7)7. The ‘Pigeon Hole’ is a _______ (4)10. A wine producing region of Spain (5)11. Raw fish (5)12. Main artery from the heart (5)13. Spiky sea creatures which are edible (7)15. What viruses and bacteria do (6)16. Fire pottery in this (4)18. Seeking attention (5)21. An old refrigerator coolant (1,1,1,)Answers to Dec 2005. Across: 1. Carbon dioxide, 6. Runs at a loss, 8. Yoghurt, 10. Aga, 12. Ice, 15.Gnu, 16. Acronym, 18. Depressants. 19. Streptococcus. Down: 1. Cardiologists, 2. Randy, 3. Orange,4. Install, 5. Educationists, 7. Opts, 9. Ulcer, 11. Ecuador, 13. Camp, 14. UNESCO, 17. Manic.44