History of the Enigma
The Enigma machine, patented in 1919, displays a keyboard of the twenty-six letters in the pattern of the normal German typewriter, although without numeral or punctuation keys (Stripp 83). It contains three basic parts: “a typewriterlike keyboard on which the plaintext is typed, an internal electromechanical system that converts plaintext to ciphertext, and a display system in which the ciphertext is displayed (Newton 99). The original 1918 Enigma machine contained three rotors, which is the area in charge of transcribing one letter to another and weighed more than one hundred pounds at fifteen inches high. Later editions adopted a more streamline appearance for simpler use and transportation, only weighing fifteen pounds at four inches in height (Newton 100).
Enigma Machine: How it Works
Enigma Machine: How it was Used
- Allsop, F. C. Practical Electric Bell Fitting, a Treatise on the Fitting-up and Maintenance of Electric Bells and All the Necessary Apparatus, with Nearly 150 Illustrations. (London : E & F. N. Spon, 1892).