Bletchley Park is well known as the setting for some of the most brilliant and audacious acts of code breaking during both world wars. In fact, it is generally accepted that the work of outstanding individuals like Alan Turing and Alfred 'Dilly' Knox was responsible for shortening the Second World War by up to two years, saving countless thousands of lives on all sides.
This weekend Bletchley Park marked the 70th anniversary of the outbreak of WW2 with a unique gathering of code-breaking devices from all over the world. Machinery and other rare manual ciphers came from far and wide including exhibits from Germany and Canada. Some items were even supplied by the Ministry of Defence and other government agencies, and some very rare machines were seen in public for the first time since the end of the Cold War.
Here are some of the highlights.
The Gretag AG TC-53 on-line cipher was designed by Edgar Gretener and made in Switzerland. It has a total of 12 rotors, the first four of which are 'scrambler' rotors. To the right are eight notched rotors, which control the rotation of the first four. This is one of the last rotor machines made before modern electronic scramblers took over.
The Fialka, pictured above, was one of the post-war machines developed by the Soviet Union and has direct links back to the original Enigma machines. It is, however, far more sophisticated and complex with 10 wired rotors, a punch tape reader and puncher and the ability to print either plain or cipher text. The Fialka uses punched cards to achieve the same results as later Enigma models' plug boards.
The Standard Military Enigma, pictured left, was used by both the German Army and Air Force. This machine was manufactured in 1935 and was almost certainly used during the invasion of Norway. It is fitted with a very rare deflector unit (UKW-D), which was issued in 1944 to Norwegian Heer and Luftwaffe units. The deflector can be reset on a daily basis making it much harder to crack.
The Enigma K932, shown above, has three wired rotors and a settable reflector that does not move during operation and there is no plugboard on the front panel. This machine was issued to German railways and was used to code messages about train movements. The system was broken at Bletchley Park and was codenamed 'Rocket'.
The BC38 was used as a 'back at base' machine and could decipher and encipher C38 messages. It had a keyboard and an electric motor and was intended for use in clean and dry conditions so did not see frontline action.
The C35 and C36 were cipher machines designed by the Ukranian cryptographer Boris Hagelin for the Swedes in the 1930s. These were the first of Hagelin's machines to feature the pin and lug mechanism later used by many makers. The French had asked for a machine small enough to fit into an army great coat pocket and this was the result. These early 'portable' machines were thought to have weak encryption and were rejected by the US Army, although the French still bought 5,000.
This is a remarkable fully working replica of an Enigma machine built completely from scratch by enthusiast Ken Hutchins. All of the major components are made from clear acrylic allowing the inner workings of the device to be seen in action.
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