A 1932 memorandum on rum-runner’s cryptosystems

During the prohibition era, organized crime made phenomenal amounts of money through illegal smuggling. Eventually, their messages were enciphered. By the late 1920s and early 1930s, these cryptosystems became rather sophisticated. Here is a memorandum form Elizebeth Friedman to CMDR Gorman in January or 1932 which gives an indication of this sophistication.
EF-to-CMDR-Gorman_1932-01-28_p1
EF-to-CMDR-Gorman_1932-01-28_p2

Many thanks to the George C. Marshall Foundation, Lexington, Virginia, for providing this reproduction!