Arnold I. Dumey (1906-1995) was the co-inventor of the postal sorting machine and cryptanalyst first for SIS and then NSA.
[1] During World War II he worked for the Army Signal Corps[2] and at Arlington Hall, headquarters of the US Army's Signals Intelligence Service (SIS) cryptography, under William and Elizabeth Friedman on breaking the German and Japanese codes.
Later, as a consultant, he co-invented the postal sorter and wrote the code that is used on the front of all USPS envelopes and packages in order to facilitate delivery.
The Dumey Microsecond was a crucial event that Arnold claimed was common to all projects: It is that microsecond during which you can impact the flow of, or design of, a project.
Through the early 1970s, Dumey, then working for the Institute for Defense Analysis in Princeton, was the longest-serving member in the history of the NSA scientific advisory board.