A hitherto unwritten chapter in WWII history, in which the worlds of cloak and dagger and geekdom collide. Most of the extensive literature surrounding the decipherment of the German navy's Enigma code centers on Bletchley Park and the British contribution. When German cryptographers added a fourth rotor to Enigma in 1942, write journalist/mystery novelist DeBrosse (Southern Cross, 1994, etc.) and Burke (History/Univ. of Maryland), they created a coding system that they were sure was unbreakable: "Theoretically, at least, the number of ciphering possibilities generated by the advanced naval Enigma of 1942 was far greater than the number of all the atoms in the observable universe."

The capture of several Enigma machines at sea, and the deconstruction of their complex wiring reduced the number of possibilities, but not enough. Enter the good folks at the National Cash Register Corporation of Dayton, Ohio, newly put to work for the Allied war effort, and NCR's head of electrical research, Joseph Desch. The British were at first reluctant to share data with the Americans, but in time they admitted Desch and company as junior partners in the Enigma-cracking enterprise, and with a little help from the legendarily eccentric British physicist Alan Turing, the NCR staff eventually developed a machine capable of deciphering encoded German naval communications.
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