Ciphers and Codes. Admiralty House, what went on in room 40?

Room 40, known as 40 O.B. (Old Building), Admiralty House, was used by the cryptanalysts of the British Admiralty, Naval Intelligence Section. In October of 1914, the director of naval intelligence, Rear Admiral Henry Oliver and his team were tasked with intercepting and decrypting German wireless and telegram communications traffic. They were said to have intercepted and translated over 15,000 German communications, the most notable being the Zimmermann Telegram in 1917, which exposed the alliance that Germany had with Mexico. Which was one of the reasons behind America eventualy being drawn into the Great War.

If you would like to attend any of our monthly meetings, we meet on the first Saturday of each month throughout the year. Please come and visit, you are assured a warm and friendly welcome from our members and guests, and you will be able to enjoy many interesting and informative talks from our invited speakers. These presentations are then followed by a Q&A session and a lively interaction on the day's subject between our guest and members. Membership of The Western Front Association is optional, not essential,  for anyone wishing to attend our branch meetings. I would say, however, that membership of the WFA is of great benefit to anyone wishing to research the military past of family members, or those looking into people and events in and around the Great War. Also, the support and information available from the current membership, trustees, and publications is second to none. With easy access to the numerous documents now available to the association on the new website, membership has a great deal to offer. The magazines accompanying membership, ‘Bulletin and Stand To!’, are regularly sent to members throughout the year, and are a great source of articles and information on the Great War.