In the lead-up to World War II, Gordon Welchman was one of the earliest recruits to Bletchley Park, a center known as Station X established by Britain’s Government Code and Cypher School to collect, decrypt and analyze encrypted messages. Welchman performed metadata analysis (that is, analysis of data that provides information about other data) of German communications to learn how German forces were organized, their location, movements and activities. In fact, Welchman is credited with developing metadata analysis. However, Welchman's main was as head of Hut Six, the section at Bletchley Park responsible for breaking German Army and Air Force Enigma ciphers. In 1982, Welchman’s book about his work at Hut Six was published. Notwithstanding the passage of time, Welchman lost his security clearance and with it, his ability to make a living. The book was not banned but a relatively small number were actually sold. Many copies were pulped. Welchman was devastated and never fully recovered.

New York: McGraw-Hill, 1982. 1^st printing. 326 pages. Hardcover book with dustjacket. Minor soiling and rubbing to both book and dustjacket and some edgewear and some spotting due to age-toning at places on the dustjacket. Overall, both are in VERY GOOD condition.