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 powers in Europe. In 1774 an arrangement was made with Abbot Georgel, the secretary at the French Embassy, which gave him access to a twice-weekly package of information in exchange for 1,000 ducats. He then sent these letters, which contained the supposedly secret plans of various monarchs, straight to Louis XV in Paris.
The Black Chambers were effectively making all forms of monoalphabetic cipher insecure. Confronted with such professional cryptanalytic opposition, cryptographers were at last forced to adopt the more complex but more secure Vigenère cipher. Gradually, cipher secretaries began to switch to using polyalphabetic ciphers. In addition to more effective cryptanalysis, there was another pressure that was encouraging the move toward securer forms of encryption: the development of the telegraph, and the need to protect telegrams from interception and decipherment.
Although the telegraph, together with the ensuing telecommunications revolution, came in the nineteenth century, its origins can be traced all the way back to 1753. An anonymous letter in a Scottish magazine described how a message could be sent across large distances by connecting the sender and receiver with 26 cables, one for each letter of the alphabet. The sender could then spell out the message by sending pulses of electricity along each wire. For example, to spell out hello, the sender would begin by sending a signal down the h wire, then down the e wire, and so on. The receiver would somehow sense the electrical current emerging from each wire and read the message. However, this “expeditious method of conveying intelligence,” as the inventor called it, was never constructed, because there were several technical obstacles that had to be overcome.
For example, engineers needed a sufficiently sensitive system for detecting electrical signals. In England, Sir Charles Wheatstone and William Fothergill Cooke built detectors from magnetized needles, which would be deflected in the presence of an incoming electric current. By 1839, the Wheatstone-Cooke system was being used to send messages between railway stations in West Drayton and Paddington, a distance of 29 km. The reputation of the telegraph and its remarkable speed of communication soon spread, and nothing did more to popularize its power than the birth of Queen Victoria’s second son, Prince Alfred, at Windsor on August 6, 1844. News of the birth was telegraphed to London, and within the hour The Times was on the streets announcing the news. It credited the technology that had enabled this feat, mentioning that it was “indebted to the extraordinary power of the Electro-Magnetic Telegraph.” The following year, the telegraph gained further fame when it helped capture John Tawell, who had murdered his mistress in Slough, and who had attempted to escape by jumping on to a London-bound train. The local police telegraphed Tawell’s description to London, and he was arrested as soon as he arrived at Paddington.
Meanwhile, in America, Samuel Morse had just built his first telegraph
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 powers in Europe. In 1774 an arrangement was made with Abbot Georgel, the secretary at the French Embassy, which gave him access to a twice-weekly package of information in exchange for 1,000 ducats. He then sent these letters, which contained the supposedly secret plans of various monarchs, straight to Louis XV in Paris.
The Black Chambers were effectively making all forms of monoalphabetic cipher insecure. Confronted with such professional cryptanalytic opposition, cryptographers were at last forced to adopt the more complex but more secure Vigenère cipher. Gradually, cipher secretaries began to switch to using polyalphabetic ciphers. In addition to more effective cryptanalysis, there was another pressure that was encouraging the move toward securer forms of encryption: the development of the telegraph, and the need to protect telegrams from interception and decipherment.
Although the telegraph, together with the ensuing telecommunications revolution, came in the nineteenth century, its origins can be traced all the way back to 1753. An anonymous letter in a Scottish magazine described how a message could be sent across large distances by connecting the sender and receiver with 26 cables, one for each letter of the alphabet. The sender could then spell out the message by sending pulses of electricity along each wire. For example, to spell out hello, the sender would begin by sending a signal down the h wire, then down the e wire, and so on. The receiver would somehow sense the electrical current emerging from each wire and read the message. However, this “expeditious method of conveying intelligence,” as the inventor called it, was never constructed, because there were several technical obstacles that had to be overcome.
For example, engineers needed a sufficiently sensitive system for detecting electrical signals. In England, Sir Charles Wheatstone and William Fothergill Cooke built detectors from magnetized needles, which would be deflected in the presence of an incoming electric current. By 1839, the Wheatstone-Cooke system was being used to send messages between railway stations in West Drayton and Paddington, a distance of 29 km. The reputation of the telegraph and its remarkable speed of communication soon spread, and nothing did more to popularize its power than the birth of Queen Victoria’s second son, Prince Alfred, at Windsor on August 6, 1844. News of the birth was telegraphed to London, and within the hour The Times was on the streets announcing the news. It credited the technology that had enabled this feat, mentioning that it was “indebted to the extraordinary power of the Electro-Magnetic Telegraph.” The following year, the telegraph gained further fame when it helped capture John Tawell, who had murdered his mistress in Slough, and who had attempted to escape by jumping on to a London-bound train. The local police telegraphed Tawell’s description to London, and he was arrested as soon as he arrived at Paddington.
Meanwhile, in America, Samuel Morse had just built his first telegraph
Similar Books
