A D V E N T U R E S in C Y B E R S O U N DClaude Chappe : 1763 - 1805
The first developement of a useful optical telegraph was in the time of the French Revolution, the epoche of the arising capitalism. The Revolutionary France was threatened by inner and outer opponents. This situation made a new communication system necessary. The civilian Claude Chappe, a former priest, invented a mechanical-optical telegraph. It consisted of a column with a moveable crosswise beam. This beam also had two moveable arms. With ropes it was possible to show many different signal pictures, all together 196 (with upper and lower case letters, punctuation marks and numbers). The equipment stood on rooftops or towers and was visible from afar. The first telegraph line of this sort was put into operation in 1794. In this time corps of voluntary soldiers were defending France against Austria and other Feudal Powers. The telegraph line consisted of 22 stations and linked Lille with the capital Paris, a distance of over 240 kilometers. It only took 2 to 6 minutes to transfer a message, riding couriers would have needed 30 hours. In 1894, when the revolutionary army conquered back the city Le Quesnoy, the message of this event was already in Paris one hour later, but only because there was no fog!
Claude Chappe (1763 - 1805) was the grandson of a French baron and was raised for the church. He lost his religious sinecures as a result of the Revolution and along with his four (also now unemployed) brothers turned to working on a mechanical semaphore system for telegraphy. They obtained the support of the Revolutionary Convention and in 1794, after several design changes, succeeded, despite the violence of the Revolution, in establishing a chain of fifteen tower stations linking Paris and Lille, 120 miles to the north. France established a national system which was finally replaced by the electric telegraph beginning in 1846. In 1804, Claude Chappe, depressed by illness and by mounting claims of plagiarism (after all, the military had used semaphore systems) threw himself down the well at his hotel.
Claude Chappe, (b. Dec. 25, 1763, Brûlon, Fr.--d. Jan. 23, 1805, Paris), French engineer and cleric who converted an old idea into a reality by inventing the semaphore visual telegraph. His brother Ignace Chappe (1760-1829), a member of the Legislative Assembly during the French Revolution, strongly supported Claude's proposal for a visual signal line between Paris and Lille, near the war front. With the Assembly's backing, the Chappes built a series of towers on heights between the two cities. Each tower was equipped with a pair of telescopes, one pointing in either direction, and with a two-arm semaphore (a word derived by Chappe from the Greek for "bearing a sign"). Each arm of the semaphore could assume seven clearly visible angular positions, making possible 49 combinations that were assigned to the alphabet and a number of other symbols. In August 1794 the Chappe semaphore brought to Paris in less than an hour the news of the capture of Condé-sur-l'Escaut from the Austrians. Other lines were built, notably between Paris and Toulon, and the system was soon widely copied elsewhere in Europe. Chappe was accorded the title telegraph engineer, but when rivals contested the priority of his invention, his natural tendency to melancholia was apparently deepened; in a fit of depression he committed suicide.
A full description of Chappe's work is located at: http://www.it.kth.se/docs/early_net/ch-1-2.html and a work devoted to Chappe's system and late 18th century politics is located at: http://www.telemuseum.se/historia/optel/otsymp/Frankrike.html
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