DSCN1219

A replica of Alan Turing’s Bombe decoding machine at Bletchley Park. The engineering design and construction was the work of Harold Keen of the British Tabulating Machine Company. It was a substantial development from a device that had been designed in 1938 by Polish Cipher Bureau cryptologist Marian Rejewski, and known as the "cryptologic bomb" (Polish: "bomba kryptologiczna"). The function of the Bombe was to discover some of the daily settings of the Enigma machines on the various German military networks; specifically the set of rotors in use and their positions in the machine, and the wiring of the plug board.