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The Hebern Rotor Machine was an electro-mechanical encryption machine built by combining the mechanical parts of a standard typewriter with the electrical parts of an electric typewriter, connecting the two through a scrambler. It is the first example (though just barely) of a class of machines known as rotor machines that would become the primary form of encryption during World War II and for some time after, and which included such famous examples as the German Enigma. ==History== Edward Hugh Hebern was a building contractor who was jailed in 1908 for stealing a horse. It is claimed that, with time on his hands, he started thinking about the problem of encryption, and eventually devised a means of mechanizing the process with a typewriter. He filed his first patent application for a cryptographic machine (not a rotor machine) in 1912.〔(Patent 1,086,823 ), filed 3 June 1912.〕 At the time he had no funds to be able to spend time working on such a device, but he continued to produce designs. He made his first drawings of a rotor-based machine in 1917,〔Bauer, FL. The origin of the rotor idea. 14.1.3.1 Hebern. In:''The History of Information Security: A Comprehensive Handbook'', Karl Maria Michael de Leeuw & Jan Bergstra, eds. Elsevier, 2007, p. 385.〕 built a sample, and patented it in 1918. He continued to make improvements, adding additional rotors.〔 Agnes Driscoll, the chief civilian employee of the US Navy's cryptography operation (later to become OP-20-G) between WWI and WWII, spent some time working with Hebern before returning to Washington and OP-20-G in the mid-'20s. Hebern was so convinced of the future success of the system that he formed the Hebern Electric Code company with money from several investors. Over the next few years he repeatedly tried to sell the machines both to the US Navy and Army, as well as to commercial interests such as banks. None was terribly interested, as at the time cryptography was not widely considered important outside governments. It was probably because of William F. Friedman's confidential analysis of the Hebern machine's weaknesses (substantial, though repairable) that its sales to the US government were so limited; Hebern was never told of them. Perhaps the best indication of a general distaste for such matters was the statement by Henry Stimson in his memoirs that "gentlemen should not read each other's mail". It was Stimson, as Secretary of State under Hoover, who withdrew State Department support for Herbert Yardley's American Black Chamber, leading to its closing. Eventually his investors ran out of patience, and sued Hebern for stock manipulation. He spent another brief period in jail, but never gave up on the idea of his machine. In 1931 the Navy finally purchased several systems, but this was to be his only real sale. There were three other patents for rotor machines issued in 1919, and several other rotor machines were designed independently at about the same time. The most successful and widely used was the Enigma machine. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hebern rotor machine」の詳細全文を読む スポンサード リンク
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