Demystifying the Bombe cover

On 4th September, 1939 Alan Turing reported for duty at the Government Code & Cypher School at Bletchley Park. in 1939 the immediate challenge was to find a way to read messages enciphered on the Enigma machine. Together with another mathematician, Gordon Welchman, Alan Turing designed a new type of machine, the Bombe, which would give the codebreakers a breach in the security wall constructed by the Enigma.

This book explains the basics of the Bombe’s design and how it helped with the cracking of Enigma messages.

The book was written in 2014 as a companion to the live demonstrations of the replica Bombe now on display at The National Museum of Computing.

At Bletchley Park the exhibition Hut 11A: The Bombe Breakthrough opened on 23 March 2018. This permanent exhibition tells the story of the Bombe machines in the actual location that housed the machines which broke Enigma.

You can also listen to Dermot Turing discussing the unsung heroes of the Bombe machine story.

…… Demystifying the Bombe is not fluff. It tackles head-on such bombe-related topics as cribbing and the creation of loops, how the bombe’s feedback loop works, testing plugboard hypotheses, the diagonal board, and the operation of the checking machine. The combination of clear explanations and enlightening images makes these topics understandable.

Demystifying the Bombe meets all the requirements to be a souvenir of a visit to Bletchley Park, but it is much more than that. Anyone who wants to understand the British bombe should explore this brief book. It truly does demystify the bombe.
Chris Christensen, Cryptologia, 2016