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2012 Meetings


28 November 2012

A Tribute to Alan Turing

A celebration of the life of Alan Turing was held with part of his archive from Sherborne School on display and four speakers covering different periods of his life.

1) Turing’s School Days – Rachel Hassall Rachel is a very well qualified archivist with wide experience and currently the Archivist at Sherborne School. The Turing Archive was given to the School by his mother in September 1965, eleven years after his death. The archive has also been seen at Bletchley Park, the Science Museum and Harvard University. Alan was born in London on 23 June 1912 As a young child his parents were in India and he was boarded in England. Aged 9 he went to Hazelhurst Prep School in Sussex and his natural curiosity and inventiveness came out in his letters to his parents who responded by giving him books to further wet his appetite! From 1926 to 1931 he attended Sherborne School, following a fraught trip from France caused by the General Strike closing down all public transport. He was put into Wescott house on Horsecastles under a very good housemaster. He was somewhat shy initially and only responded well to science subjects with English, History and Languages being particularly poor, as attested by his school reports. He improved gradually to be more of an all-rounder including making Sergeant in the OTC and finishing as a prefect and winning the maths medal. From 1931 to 1934 he went to King’s College, Cambridge with a Scholarship, gaining first class honours in mathematics. 2) The Pre-War Years – Mike Tarlton Mike worked as a software engineer with Plessey for several years. Currently he is a freelance software instructor. He has been a regular attender and contributor to the Science Cafe since its inception. In 1935 Alan was elected a Fellow of King’s College at the age of 22. He won the Smith’s prize for his fellowship dissertation in 1936 and published his most important theoretical work On Computable Numbers, with an Application to the Entscheidungsproblem, a foundation of modern computer science, proposing an universal abstract ‘automatic machine’ (now known as the Turing Machine) to compute from first principles. Mike then showed an on-screen demonstration of the principles involved. Alan moved to Princeton from 1936 to 1938 to study under the logician, Alonzo Church. There he gained his PhD with the thesis Systems of Logic based on Ordinals. He then returned to Cambridge. 3) Bletchley Park – Roger Knight Roger is a leading member of CADAS and a big Turing fan. Turing was recruited to the Government Code and Cypher School in 1938 and a Captain Ridley was tasked with finding a suitable quiet spot to set up a secret facility for code breaking in preparation for the seemingly inevitable war. He found Bletchley Park which was near Oxford (Hitler’s proposed base for ruling Britain - and hence less likely to be bombed). He found Bletchley while pretending to be part of a hunting party. Churchill called Bletchley ’the Goose that laid the Golden Egg, but didn’t cackle’. Alan took up residence there for the remainder of the war, helping with all the major projects which cracked the German codes and made a major contribution to winning the war while staying totally low profile (The main radio aerial was strung from an aurora tree to the radio room). The effort was well supported by other mathematicians, scientists and engineers, with wonderful supporting staff. Gordon Welshman built the first ‘Bombe’, Bill Tutte analysed the Lorenze code machine without seeing one beforehand. Tommy Flowers built the Heath Robinson machine out of ex GPO equipment. The first Enigma codes were broken in 1941 allowing positions of U-boats to be known. In 1942 in analysing the German Tunny cipher machine Alan invented ‘Turingismus’, the first systematic method for breaking codes and basis for programming the later Colossus machine (500+ valves). Visited USA to liaise with American code breakers. He was also supported throughout the war by a Teddy Bear named ‘Podgy’! 4) Turing at Manchester – Allan Lawton Allan has recently retired as a Chief Software and Systems Engineer at Plessey (now Thales) In 1945, Alan accepted a post at the NPL Teddington and designed the ‘ACE’ computer for them. He was also awarded the OBE for his war work. He became disillusioned with the higher management’s ‘lack of vision’ of computers and joined Manchester University in 1948 as deputy director of the computing laboratory (there was no director!). Just prior to this he gave his first known lecture on computer intelligence which was a precursor to the Turing Test for Computer Intelligence still recognised today. In 1950 he published ‘Computing Machinery and Intelligence’ and wrote the programming handbook for the Manchester Electronic Computer. In he 1951 joined the team designing the Ferranti Mk I computer to be used for Atomic Bomb research and wrote the programming manual. He was elected a Fellow of the Royal Society. In February 1952 he was arrested on a charge of homosexuality and placed on probation on condition he took oestrogen and was denied access to any secret material as a security risk! He published The chemical basis of Morphogenesis. It was a model of the development of organisms from simple single celled ‘entities’ to the complex structures we see in the developed being. It led the world in the field of Developmental Biology and is often quoted by leading biologists in this field today. His theoretical work in this field was not supported by direct physical evidence until work published in December 2006. On 7 June 1954 he died of cyanide poisoning, said to be self administered.

24 October 2012

Science and Managing African Dryland Environments

Dr Mike Mortimore

Dr Mike Mortimore, a geographer by training, explored this subject of managing African dryland environments. He started by comparing the methodology of the natural and social sciences. The model proposed for the natural sciences was: hypothesis leading to experiment; weighting of the experimental results leading to paradigm changes and ending with ecosystems. In the social sciences we have: datasets; generalisations from the datasets; giving weight to the generalisations leads to human systems. The drylands of Africa are social-ecological systems which are best operated in a holistic framework.

  The drylands are of high aridity and many people born here died before they reach five years old. These areas also suffer great rainfall variations. The term 'carrying capacity' for ecosystems was introduced. This involved knowing how many cattle could be supported per hectare. The system of having fenced-in ranches did not work well here. People had to find by experiment the maximum numbers supported by the natural vegetation. This had to be balanced against breeding as many as possible. Some of the problems were solved by moving the cattle around. He also spoke about how owners bonded with their animals.

  A great problem was the gap between local knowledge and scientific knowledge and the need to balance expert outside knowledge with experience of indigenous pasturalists. He suggested that local systems were more efficient than outside scientific knowledge.

  Quite often there were crop failures after drought and locals had to find ways of coping. The mechanisation of labour gave rise to problems of its own. Although some of the work could be done by tractors, these were only efficient if they could be maintained on a regular basis. Animal assisted human labour was more reliable. In order to make the most use of the land inter-cropping was used in which several varieties of crop were grown on the same area of land. Despite all the difficulties the population of Nigeria had doubled in 60 years up to 1991.

  Dr Mortimer gave us a feeling of the problems faced by those inhabiting the drylands of Africa. There was a lively discussion at the end.

26 September 2012

Follow That Cuckoo and Other Stories: Research into Migrant Birds

Dr.Phil Atkinson

British Trust for Ornithology

  The migrant birds of Europe and the Western Palearctic are endangered, owing to a number of global factors. Many species, including wagtails and nightingales, have declined dramatically since data was first collected in 1968, as can be clearly seen in the recent statistics collated for the BTO Bird Atlas, due out in 2013. Phenology, the study of the effects of climate change on migration, is a major interest of the BTO. In conjunction with the RSPB, studies were undertaken to examine the plight of the swallow, which faces an annual round trip of 30,000km.

  Social scientists, ecologists and ornithologists are heavily involved in studies in five sites in sub-Saharan Africa examining possible links between migration to the continent and failure of many birds to survive. Climactic conditions on the flight path, vegetative growth and fire all contribute to difficulties faced by individual birds. Land use is changing rapidly, for example palm oil plantations in west Africa are a poor habitat for migratory birds. The land which was previously covered with deciduous woodland is being destroyed as timber needs rise. Wetlands, dry season savannah, equatorial regions have all become compromised. Birds are pre-programmed to fly when they feel it is time, but climate change in Europe, with spring starting earlier, means many birds miss out on spring growth and insect life necessary for breeding.

  Data collection in the field is difficult owing to the large tracts of the African continent which are war-torn. Two teams work in Ghana and Burkina Faso between October and March concentrating on inter-African migration of species such as the grey-headed kingfisher, hoopoe and Setti’s warbler. Species which settle in the northern sahelian are doing well (sedge warblers, sand martins, whitethroat and chiffchaff).Those travelling further south are suffering badly (nightingales, wood warblers and spotted flycatchers). By using satellite tagging and geolocators, birds can be tracked on migratory paths reasonably successfully, but the technology is costly. Back at base in Norfolk data appears daily, recording latitude, longitude, tag temperature, name of bird, all important in order to track a given individual or flock. Habitat suitability models are good; indicators of where birds stop over, where they die, environmental behaviours and habitat selection are now better understood.

  The cuckoo is one species which migrates as an individual making survival much more challenging. In 2012 15 cuckoos were named and tagged, 5 in Wales, the remainder in England and Scotland. All bar one left the UK. 4 birds took a SW route through Spain and Liberia, 3 of these have died, one became confused and made its way to Switzerland. Two birds died on their desert crossing. Important work is being undertaken but there is still more to be done. With tags costing £3000, financial support is always welcomed.

25 July 2012

Seeds as natural capital

Prof Hugh Pritchard

Royal Botanic Gardens

Professor Pritchard who is based at the Royal Botanic Gardens, Wakehurst Place gave a lecture about seeds as a vital natural resource. The global project known as The Millenium Seedbank Project has several centres around the world including Seed Cathedral in Beijing, and seeds from a variety of countries are stored in each one. 

   Prof Pritchard explained that the world’s ecosystems are under great threat due to a predicted rise in global temperatures of between 2-5C by 2100, and the destruction of tropical forests: 20% between 1960-1990. The combination of these and other factors means that food production, water supply, and biodiversity are at great risk of breaking down, hence the need to bank seeds.

    Globally, 80% of our food comes from 8 grains and 4 tubers. In addition 75% of the world’s population uses complementary medicine based on plants, and 50% of all synthetic drugs come from plants. We have to conserve them.

   The sequence used to store most species is: collect-dry-clean-purify-package-store at minus 20C. Then each year a batch of each species has to be tested for germination. Some species do not respond well to this treatment however. For example they may be sensitive to drying, making them non-bankable. More sophisticated techniques are needed, and research into this is progressing. All this makes the cost of the project run into billions, yet the value to world of our biodiverse ecosystem is estimated in trillions!

27 June 2012

Hot Rocks in Eden

Guy Macpherson-Grant

EGS Energy

The talk outlined the attempts to exploit deep geothermal energy as a source of carbon-free energy, in the context of declining oil supplies, particularly low-sulphur types. Current developments and projects operating in France and Germany were described. The recent Sinclair Knight Merz (SKM) report’s key findings include:-

The resource is widely spread around the UK with ‘hotspots’ in Cornwall, Weardale, Lake District, East Yorkshire, Lincolnshire, Cheshire, Worcester, Dorset, Hampshire, Northern Ireland and Scotland;

Cost reduction potential is exceptionally high;

Deep geothermal resources could provide 9.5GW of baseload renewable electricity – equivalent to nearly nine nuclear power stations – which could generate 20% of the UK’s current annual electricity consumption;

Deep geothermal resources could provide over 100GW of heat, which could supply sufficient heat to meet the space heating demand in the UK;

Despite this significant potential, the UK support regime is uncompetitive with other European countries.

EGS is looking in the South West for areas of granite which are accessible and where the rock is already fractured to provide a wider volume of hot rock; as the depth where heat transfer takes place increases to the order of 4.5 – 5 km the circulated water can reach the surface at about 180° C enabling generation of electricity by steam turbines and low grade surplus heat to be available for district heating.

The geology of parts of Cornwall is suitable for the application of the techniques developed by EGS Energy. In addition there is sufficient water in the area to provide a reservoir for the system. In order to determine the area where the initial EGS Plant will be established, EGS has undertaken an analysis of geological data and a suitable site has been identified at the Eden Project.

In collaboration with the Eden Project EGS Energy proposes to build the UK's first geothermal power plant generating both heat and electricity. With a capacity of 4MWe and the ability to generate around 95% of the time, it should produce enough electricity to supply Eden and the equivalent of around five thousand households, as well as heating for the biomes and potentially some district heating (depending on economics and logistics). It is hoped that power will be delivered from late 2013 but this depends on many factors: planning permission, drilling rig availability, drilling progress, and so on.

Questions raised concerns about extraction and disposal of pollutants, potential problems similar to those from “fracking” and low overall efficiency.

23 May 2012

How do you measure the size of a raindrop?

Dr Andrew Eccleston

School of Marine Science & Engineering, Plymouth University

Andrew Eccleston, a lecturer in Nautical Studies at the University of Plymouth, gave our Science Café an introduction to the scientific study of raindrops and explained why it was important to know the distribution of their sizes in various conditions.

He pointed out that the damage caused by raindrops to crops and properties was dependant on their sizes. He then discussed three methods that were used to measure their sizes; dough pallets, spots on filter paper and a device called a disdrometer. The distribution of sizes varied considerably from soft rain, through heavy showers, right up to thunderstorms.

He went on to point out that the sizes of the drops altered considerably their ability to reflect the radio waves used in weather radar receivers. It was also important to know the sizes of the drops in order to estimate how much water there was in clouds. The forecast maps given on television was a composite of the results from ground stations, weather radar and weather satellite pictures.

There was a lively set of questions and discussions at the end.

25 April 2012

Insects as flying machines

Dr Robin Wootton

Honorary Research Fellow, University of Exeter

Dr Robin Wootton gave us a fascinating insight into the aerobatics of insects at our April meeting. We learned that they are the oldest flying animals, going back 300 million years, and also the smallest with Caraphractus (the Fairy Fly) being only 0.2mm in length. Some of the extinct dragon flies had a wing span of over 2.0 metres, and other insects can accelerate as fast as a space rocket ! How do they do it?

The answer is not simple, but an essential component that they uniquely possess is Chitin, with which they make their exoskeleton and all their appendages. It is a complex of protein and carbohydrate which is strong, light, and flexible. Indirect muscles alter the shape of their exoskeleton, and in so doing cause the wings to move up and down. Direct muscles attached to the wing base alter the shape and camber of the flapping wing so that the variety of movement is enormous.

Finally they have a unique respiratory system made of tracheoles which takes respiratory gases directly into and out of the wing muscles. Their compound eyes give them superb navigational ability, detecting danger/movement very quickly. In fact it is a good job they do not have our large brains – or they would be in charge! 

28 March 2012

The history and mathematics of codes

Martin Crozier

Head of Mathematics, Leweston School

At our March meeting (28th) we were treated to a fascinating, instructive and entertaining lecture on codes and cryptography, by Martin Crozier, Head of Mathematics at Leweston School. He started with a historical introduction to the subject. He told us that Caesar used simple substitution codes in which the letters in a message were replaced by different letters according to some basic rules. Caesar used what has become known as the Caesar Wheel. This device consisted of two wheels, one slightly smaller than the other, with the letters of the alphabet written along their circumferences, and mounted on an axis, so that the discs can be rotated with respect to each other. The code was then obtained by rotating one disc with respect to the other and substituting the one set of letters with the other adjacent set.

He pointed out that simple substitution codes can be easily cracked by an analysis of the frequency with which letters turn up in the encoded message. He also told us that Mary Queen of Scots used more sophisticated codes when conducting her more secret correspondence. Martin then discussed the Vigenere Square, which consisted of a grid of 26 by 26 characters, where the letters of the alphabet are written, but shifted left one character as you go down. To use this square you and your spy ring need to agree on a code word or phrase. The longer the code word the more difficult it is to break the code.

After mentioning a variety of other coding techniques, he went on to discuss the mathematics of cryptography, and the use of prime numbers when setting up codes. Crozier then discussed how important codes and ciphers had become since the development and use of computers and the very widespread use of the internet. This was particularly true for online banking and purchasing goods over the internet.

The evening ended with several questions from the floor, and there was a lively discussion on some of the points raised by talk.

22 February 2012


Wolfgang Grulke

Chairman Emeritus, FutureWorld International Limited


            “For more than two decades I worked in business development and strategy at IBM. Then I founded the global business and technology think tank FutureWorld where we have worked with hundreds of organizations globally, encouraging them to stay relevant in a radically different future. We helped clients start more than 100 new breakthrough businesses during the last decade. Both IBM and FutureWorld were amazing laboratories for learning about how executives and organizations anticipate, and act on, profound change.

Now that much of what we imagined decades ago has come to pass, and on sober reflection, what lessons have we learnt about thinking strategically, future business and technology, taking radical ideas to the bottom line, and the future of leadership?”

Where are we?

Government and Businesses don’t devote the time to thinking ahead, they spend their time managing not leading, a job which should be done by middle management not senior executives.

A recent survey showed that executives thought they spent about one half of their time on future strategy but a view of their diaries with their secretaries showed it averaged less than 5%. The future is the only destination we have and only leaders can shape it for us. Activity is not progress and thinking is also work. Learning from experience is not good enough to shape the future, none of the main developments of today were envisaged 20 years ago.

Put simplistically we have (in descending order of economic progress potential:

BRIC Summer (Brazil, Russia, India & China)

Arab Spring

US Autumn

EU Winter

Only change from Managing to Leading will reverse this and this will mean a change of culture at many levels.

Beyond 2020 – some predictions

18year olds lead in all technology matters, and this is recognised by the military (particularly in the US) and likely soon in business.

All citizens will have equal access to all knowledge.

Three quarters of retail will be online, only high street stores offering bespoke service will still be viable. (Britain has the current highest percentage of online sales as it is the only country with a still effective post office!).The first person who will live to 200 has already been born.Personal health scanners will soon be available at an affordable price (13 companies competing in the US to be the first to market this year).3D printers have already been used to fabricate an artificial heart for a mouse, by 2020 they will be used in the household for small items and widely used industrially for large items.Economic growth is necessary to progress, Democracy is not the best Government for growth and that is why China has the highest rate of the developed and developing nations.

24 January 2012

Stargazing Live with Crewkerne & District Astronomical Society

We could not "Star Gaze Live" because it was a cloudy night.  However, the evening turned out to be interesting and educational in spite of the weather.

Arthur Davis, chairman of Crewkerne and District Astronomical Society, started the proceedings with a talk on what could be seen in the night sky at the moment.  He drew attention to the principal constellations, the planets, important stars, nebulous patches of gas which emit light, and galaxies.  The talk was illustrated by several photographs which he had taken himself, and also photographs taken by professional astronomers at big observatories.  

William Budzynski, affectionately known as Bud, also from CADAS, then spoke about becoming an amateur astronomer.  He spoke about what one could see with the naked eye, about what was possible with binoculars and what telescopes of different sizes would reveal. During the break there was an opportunity for the audience to look at the telescopes on show, and to chat to the speakers about the different types

After the break Arthur Davis then gave a talk on the nature of comets, and this was also illustrated by some of his own photographs.

Bud then gave a short talk on his own telescopes, and the modifications and refinements he had made to optimise the images he could take with them. Because he does not like the cold he has modified telescopes that can be remotely operated from within the comfort of his warm studio. He showed us the equipment in his studio, including the computer used to manipulate the digital images taken from his astronomical cameras. The images of the planet Jupiter were particularly impressive.

These were several questions and a lively discussion at the end.


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