The "Big" Machines Exhibit

The Typex machine was similar to the Sigaba but was designed specifically to allow joint communications at highly secure levels between the British and the Americans. The Tunney and Sturgeon machines (referred to by American cryptologists as the "fish" machines) were both on-line cipher machines, which meant that a message could be simultaneously enciphered and transmitted, thus saving a great deal of time. Although a British cryptanalytic attack made considerable progress, the results were far slimmer than against the Enigma, both because the difficulty of attack yielded fewer breaks, and because there was a lot less traffic sent over these systems. The Jade device exhibited here is the only known example of this family of Japanese machines. Included in this family was the far more famous Purple device for the encryption of Japanese diplomatic traffic. No complete Purple device was ever captured, though a fragment of one (pictured below) was found in the courtyard of the Japanese embassy in Berlin after the city fell in 1945. Little is known of the Russian machine except that it is reported to have been captured from German forces, who had themselves evidently captured it from the Russians on the Eastern Front in World War II.