The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

by Simon Singh

Each European power had its own so-called Black Chamber, a nerve center for deciphering messages and gathering intelligence. The most celebrated, disciplined and efficient Black Chamber was the Geheime Kabinets-Kanzlei in Vienna. It operated according to a rigorous timetable, because it was vital that its nefarious activities should not interrupt the smooth running of the postal service. Letters which were supposed to be delivered to embassies in Vienna were first routed via the Black Chamber, arriving at 7 A.M. Secretaries melted seals, and a team of stenographers worked in parallel to make copies of the letters. If necessary, a language specialist would take responsibility for duplicating unusual scripts. Within three hours the letters had been resealed in their envelopes and returned to the central post office, so that they could be delivered to their intended destination. Mail merely in transit through Austria would arrive at the Black Chamber at 10 A.M., and mail leaving Viennese embassies for destinations outside Austria would arrive at 4 P.M. All these letters would also be copied before being allowed to continue on their journey. Each day a hundred letters would filter through the Viennese Black Chamber. The copies were passed to the cryptanalysts, who sat in little kiosks, ready to tease out the meanings of the messages. As well as supplying the emperors of Austria with invaluable intelligence, the Viennese Black Chamber sold the information it harvested to other ...