Alan Turing Designed Churchills Phone Scrambler

Alan Turing not only cracked Enigma but designed a voice encryption device for Churchills transatlantic phone calls to Roosevelt called Delilah. It used mathematical scrambling. By the time it was perfected transatlantic cable encryption sufficed. Turings Bombe machine also cracked the complex naval Enigma used by U-boats, helping end the Battle of the Atlantic.