Cryptography

1982 — 8vo., First Edition, with 23 plates on 16 and 5 maps (one double-page) in the text, page edges tanned as usual; original black cloth, backstrip lettered in silver, a very good, clean copy in unclipped dustwrapper, the latter mildly sunned at backstrip. The story of Reginald Hall's famous Room 40, the Admiralty's codebreaking organisation during the Great War. Like its WWII successor at Bletchley, it was successful in breaking and manipulating German naval and diplomatic codes, and its achievements had a profound effect on the outcome of the conflict. ALREADY SCARCE IN THIS CONDITION