Title: The Ultra secret
Description: Operation Ultra was designed to intercept & decode German signals sent using Enigma, the top-secret German cypher machine. F.W. Winterbotham, was the man responsible for the organization, distribution & security of Ultra. This is his personal account of the operation.
Subjects: English Personal narratives, Secret service, World War, 1939-1945, Cryptography
Places: Great Britain
People: F. W. Winterbotham (1897-)