The Enigma machine
His first design of the Enigma was called Model A and was about the size and shape of a cash register (50 kg). Then followed Model B and Model C, which was a portable device in which the result letters were indicated by lamps. The Enigma machine looked like a typewriter in a wooden box.
He called his machine Enigma which is the Greek word for "riddle". Combining three rotors from a set of five, 26 possible starting positions for each rotor, and the plug board with ten pairs of letters connected, the military Enigma had (5 × 4 × 3) × (263) × [26! / (6! × 10! × 210 (nearly 159 quintillion) different settings.
The firm's cipher machine, marketed under the name "Enigma", was initially pitched at the commercial market. There were several commercial models; one of them was adopted by the German Navy (in a modified version) in 1926. The German Army adopted the same machine (also in a modified version somewhat different from the Navy's) a few years later.
Scherbius initially had to contend with the lack of interest in his invention, but he was convinced that his Enigma would be marketable. However, the German Army did become interested in a new cryptographic device despite several disappointments in the past. The serial production of the Enigma started in 1925 and the first machines came into use in 1926.
Scherbius' Enigma provided the German Army with one of the strongest cryptographic ciphers at the time. However, the German implementation of Enigma had important flaws which enabled Polish cryptanalysts to overcome Enigma starting in 1932. The Polish work, later continued by France and especially Britain, enabled the Allies to read most German Enigma traffic.
Scherbius however did not live to see the widespread use of his machine. In 1929, Scherbius died in a horse carriage accident in Berlin-Wannsee, where he had lived since 1924.
