The British Turing Welchman Bombe-
Rebuilt at Bletchley Park by a Team of volunteers
The “Tabs” Bombe as it was called by those involved at the time, was the main machine used by the British to break the German Enigma codes. It was developed from a Polish concept and then significantly enhanced by the Mathematician, Alan Turing. Gordon Welchman devised a further improvement called the diagonal board and it was this machine which was built by BTM at Letchworth under the leadership of H.H. (Doc) Keen. At least 200 of these 1 ton [1 tonne] machines were built. They were over 7′ [2100mm] long, 6’6″ [2000mm] high and 2′ [600mm] deep and were produced throughout the five year period of the war.
In order to give some idea of the importance of this machine to the allies it is worth quoting from the diploma given to all BTM employees who worked on the Bombe when the war in Europe ended.
It will be gratifying to you to know that His Majesty’s Lords Commissioners of the Admiralty have expressed their appreciation of the rapid and efficient production of the Cantab equipment which has materially assisted in the successful prosecution of the war.