Sue Brandreth's Learning Resources

Murrell, K. and Holroyd, D. (2013) The Harwell Dekatron Computer, The National Museum of Computing

(http://www.tnmoc.org/special-projects/harwell-dekatron-witch)

The Harwell Dekatron Computer is a very early digital computer designed and built by the Electronics Division at the Atomic Energy Research Establishment at Harwell. It went into service in 1952 with the dual aims of augmenting the computing power available to the Theoretical Physics Division and to act as a test-bed for new components of interest for nuclear instrumentation. The computer used ‘Post Office’ relays for control and sequencing, and Dekatron counting tubes and cold-cathode trigger tubes for storage and arithmetic. Although slow, roughly equivalent to a skilled operator with a mechanical desk calculator, it was capable of unattended continuous operation. After several years service at AERE, it passed to the Wolverhampton and Staffordshire College, where it provided hands-on experience of computer programming for students and local school-children. Later, it was displayed at the Birmingham Museum of Science and Industry, and then held in store for some 30 years. In 2009 it was transferred to The National Museum of Computing for restoration to full working order by the Computer Conservation Society.

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Welchman, G. (2005) The Hut Six Story – Breaking the ENIGMA CODES, M&M Baldwin

Gordon Welchman worked at Bletchley Park, on the most important British de-ciphering operations of the war [WW2], from 1939 to 1945. Here, unsuspected by the Germans, the famous Enigma codes were broken, almost continuously throughout the war. Welchman was a leading figure at Bletchley Park; his brilliant mathematical mind, and imaginative attack on apparently insuperable problems, were of inestimable value in shaping the course of the war and hastening victory.
No other book has explained so thoroughly how the job was done, and how so often a flash of genius, an inspired insight, or even a stroke of luck, tipped the balance from failure to success, against all the odds.
Gordon Welchman, a talented mathematician, was educated at Marlborough, and Trinity College, Cambridge. He had taken up a post as a fellow of Sidney Sussex College when the war started, and he was an obvious recruit for the expanding codebreaking operations at Bletchley Park. He was awarded the OBE for his war work. After the war he emigrated to the USA, and continued to work on computers and their applications to security and communications. He died in 1985.

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Hill, M. (2004) Bletchley Park People – Churchill’s Geese That Never Cackled, Sutton Publishing / The History Press

The British government’s top secret Code & Cypher School at Bletchley Park, otherwise known as Station X, was the unlikely setting for one of the most vital undercover operations of the Second World War. It was at Bletchley in present-day Milton Keynes that teams of code breakers succeeded in cracking Germany’s supposedly unbreakable Enigma codes, thereby shortening the war by at least two years. Marion Hill has used the transcripts of some 200 interviews and memoirs from among the thousands of people who worked at Station X to give a remarkable insight into the daily lives of the civilian and service personnel who contributed to the breaking of the Enigma and other Axis codes. She explores their recruitment and training, their first impressions on arrival at Bletchley Park (‘Bp’), their working conditions, (including the in-house food and entertainment), and their time off in billets and beyond. These Bp workers, from boffins to debs to ex-bank clerks and engineers, were united in the need to ‘keep mum’ – even with their family and close friends. However, the stressful burden of secrecy created divisions within the organisation, and illnesses; and many felt disappointed at the lack of acknowledgement for a vital job about which they were forbidden to speak until many years later. A selection of archive photographs and illustrations accompanies the text, drawn from the Bletchley Park Trust Archive and from the personal albums of those stationed at Bletchley.

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Sale, T. (1998) The Colossus Computer (1943-1996): And How it Helped to Break the German Lorenz Cipher in WWII, M.& M.Baldwin

This is an unashamedly modest booklet, designed to provide basic information for those who know little or nothing about Colossus. It is based on a talk which the author gives to visitors to Colossus at Bletchley Park. As he was repeatedly asked by these visitors if they could have a written version of his talk, he decided to meet their requests by preparing this booklet. It thus fills a genuine need for an authoritative introduction to its subject – and who is better able to provide it than the man who masterminded the rebuild of Colossus? It may be brief, and it’s certainly cheap, but that doesn’t make it worthless. Even in 2008 you can still find writers in (for example) The Times claiming totally erroneously that Colossus was used to break Enigma codes.
If such writers had read Tony Sale’s excellent booklet, they might get the story right. Until then, I suggest that the vitriol be reserved for writers who get things wrong, not for writers who provide useful introductions to complex subjects.

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 McKay, S. (2011) The Secret Life of Bletchley Park: The History of the Wartime Codebreaking Centre by the Men and Women Who Were There, Aurum Press Ltd

Bletchley Park was where one of the war’s most famous – and crucial – achievements was made: the cracking of Germany’s “Enigma” code in which its most important military communications were couched. This country house in the Buckinghamshire countryside was home to Britain’s most brilliant mathematical brains, like Alan Turing, and the scene of immense advances in technology – indeed, the birth of modern computing. The military codes deciphered there were instrumental in turning both the Battle of the Atlantic and the war in North Africa.

But, though plenty has been written about the boffins, and the codebreaking, fictional and non-fiction – from Robert Harris and Ian McEwan to Andrew Hodges’ biography of Turing – what of the thousands of men and women who lived and worked there during the war? What was life like for them – an odd, secret territory between the civilian and the military?

Sinclair McKay’s book is the first history for the general reader of life at Bletchley Park, and an amazing compendium of memories from people now in their eighties – of skating on the frozen lake in the grounds (a depressed Angus Wilson, the novelist, once threw himself in) – of a youthful Roy Jenkins, useless at codebreaking, of the high jinks at nearby accommodation hostels – and of the implacable secrecy that meant girlfriend and boyfriend working in adjacent huts knew nothing about each other’s work.

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Hinsley, F.H. and Stripp, A. (1993) Code Breakers: The Inside Story of Bletchley Park, Oxford University Press

This is a colourful and authentic account of daily life and work at Government Communications Headquarters, Bletchley Park, the most successful intelligence agency in history.
By 1942 the codebreakers of Bletchley Park and its out-stations were breaking some 4,000 German signals a day, and almost as many from Italy and Japan, eavesdropping on enemy communications up to the highest levels of command. Their colleagues used these decrypts to produce Ultra intelligence which gave a detailed, accurate, and up-to-date picture of enemy strengths, weaknesses, and intentions. The codebreakers’ contribution to the war effort was invaluable: Churchill described them as the `secret weapon’ that `won the war’.

For the first time a group of the men and women who worked on this top-secret enterprise have combined to write their story in full. Here, they vividly describe their recruitment and training, their feelings and activities, and recall in detail their successes and failures.

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Leavitt, D. (2007) The Man Who Knew Too Much: Alan Turing and the Invention of the Computer, Weidenfeld and Nicholson