Colossus: The secrets of Bletchley Park's code-breaking computers

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OUP Oxford, Feb 23, 2006 - Computers - 480 pages
3 Reviews
At last - the secrets of Bletchley Park's powerful codebreaking computers. This is a history of Colossus, the world's first fully-functioning electronic digital computer. Colossus was used during the Second World War at the Government Code and Cypher School at Bletchley Park, where it played an invaluable role cracking enemy codes. Until very recently, much about the Colossus machine was shrouded in secrecy, largely because the codes that were employed remained in use by the British security services until a short time ago. This book only became possible due to the declassification in the US of wartime documents. With an introductory essay on cryptography and the history of code-breaking by Simon Singh, this book reveals the workings of Colossus and the extraordinary staff at Bletchley Park through personal accounts by those who lived and worked with the computer. Among them is the testimony of Thomas Flowers, who was the architect of Colossus and whose personal account, written shortly before he died, is published here for the first time. Other essays consider the historical importance of this remarkable machine, and its impact on the generations of computing technology that followed.

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User Review  - MichaelHodges - LibraryThing

A very rich history of WW2 Codebreaking genii and their machines. Not an easy subject for most laymen but well worth slugging through to the very end. The book is a compendium written by a sizeable ... Read full review

LibraryThing Review

User Review  - jztemple - LibraryThing

Only in the past few years has the story of the Colossus computers and their use to break the German's WW2 Tunny encoding machines come to light. Unlike the rather well known story of the Enigma ... Read full review


Chapter 19Setter and Breaker
Chapter 20An ATS Girl in the Testery
Chapter 21The Testery and the Breaking of Fish
Section 5T H Flowers Laboratory at Dollis Hill
Chapter 22Dollis Hill at War
Chapter 23The British Tunny Machine
Chapter 24How Colossus was Built and Operated One of its Engineers Reveals its Secrets
Section 6Sturgeon The Fish That Got Away

Chapter 3The German Tunny Machine
Chapter 4Colossus Codebreaking and the Digital Age
Chapter 5Machine against Machine
Chapter 6DDay at Bletchley Park
Chapter 7Intercept
Section 2Colossus
Chapter 8Colossus
Chapter 9Colossus and the Rise of theModern Computer
Chapter 10The PCUsers Guide to Colossus
Chapter 11Of Men and Machines
Chapter 12The Colossus Rebuild
Section 3The Newmanry
Chapter 13Mr Newmans Section
Chapter 14Max NewmanMathematicianCodebreaker and Computer Pioneer
Breaking Tunny in the Newmanry and the Testery
Chapter 16From Hut 8 to the Newmanry
Chapter 17Codebreaking and Colossus
Section 4The Testery
Chapter 18Major Testers Section
Chapter 25Bletchley Parks SturgeonThe Fish That Laid No Eggs
Chapter 26German Teleprinter Traffic and Swedish Wartime Intelligence
Technical AppendicesTo Dig Deeper
The Breaking of Tunny
Appendix 2The Teleprinter Alphabet
Appendix 3The Tunny Addition Square
Appendix 4My Work at Bletchley Park
Appendix 5The Tiltman Break
Appendix 6Turingery
Appendix 7 ΔxMethod
Appendix 8Newmans Theorem
Appendix 9Rectangling
Appendix 10The MotorWheels and Limitations
Appendix 11Motorless Tunny
Appendix 12Origins of the Fish Cypher Machines
Notes and References
Sources of Photographs

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About the author (2006)

Jack Copeland is Professor of Philosophy at the University of Canterbury in New Zealand and Director of the Turing Archive for the History of Computing, and has been studying the history of Bletchley Park since 1992. He is a contributor to Scientific American and his previous publications include Artificial Intelligence, (Blackwell, 1993), Logic and Reality (OUP, 1996), Turing's Machines (OUP, forthcoming), The Essential Turing (OUP, 2004), and Alan Turing's Automatic Computing Engine (OUP, 2005).

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