The National Cryptologic Museum Library

Last year, a widely published German technical author, Klaus Schmeh, e-mailed the library of the National Cryptologic Museum from his home in Gelsenkirchen, Germany. He needed information for an article on the Kryha cipher machine, a device popular in the 1920s. Librarian Rene Stein found articles about the machine but, even more useful, she found unpublished correspondence between Alexander von Kryha, the machines inventor, and a German who had invested in the machine. She photocopied the files and sent them to Schmeh, who used them for a talk at the 2009 Cryptologic History Symposium and for an article in Cryptologia magazine. Thus the museum advanced knowledge of the history of cryptology. When scholar Chris Christensen needed information on the US Navy cryptology correspondence courses for his article on William Wray, an early NSA mathematician, he contacted the museum library. From its collection of Special Research Histories, he obtained copies of the courses produced by the Navy between 1937 and 1946. In researching his book on the vocoder, which played a role in speech scrambling, David Tompkins met at the NSA Museum with Frank Gentges, a vocoder consultant during the Cold War. Gentges and his partner, the late David Coulter, had contributed their collection of speech cryptodevices to the museum. Gentges took Tompkins on a Cold War Secure Voice tour, explaining the HY-2 vocoder and the STU-II and STU-III phone systems. The museums audio history of secure voice was also helpful. Because Tompkins was primarily interested in the replica of the extremely secure World War II SIGSALY voice encryption system, he and Gentges spent most of the day in the library going through declassified SIGSALY files.