The autoscritcher and the superscritcher: aids to cryptanalysis of the German Enigma cipher machine, 1944-6

At the US Army Signal Security Agency during World War II, two systems were built to assist cryptanalysts in breaking messages enciphered on Enigma-type machines. Called the Autoscritcher, the first machine used relay technology. The final system, the Superscritcher, was fully electronic and contained about 3500 vacuum tubes. Both machines operated successfully. The system approach both machines was the same, but differed from that of the Bombe mechanical machines in use to do a similar job. The Superscritcher proved the practicality of electronic digital technology for computing applications. It also showed that a more flexible architecture was needed to allow the solving of more than one class of problems. An account of the design, construction, and test of the Superscritcher and the Autoscritcher is presented.<>