Figure i. — Chappe telegraph mounted on the 

 roof of the Louvre. From Beschreibung und 

 Abbildung des Telegraphen, Leipzig, 1795, pi. i. 



f I HE 19th century began with the tumult and 

 A. ferment of the French Revolution and Napoleonic 

 wars which broke many of the political and social 

 barriers that had divided Europe. Through these 

 broken barriers stretched the communication lines 

 of the revolutionary armies, in particular a semaphore 

 telegraph system (figs. 1-5) invented by Claude 

 Chappe in 1792.' Messages were sent in the Chappe 

 system by using the various positions of the crossarms 

 on a pole to symbolize numbers. Sets of such num- 

 bers could be looked up in a dictionary that correlated 

 each set with a French word. Later the Emperor 



1 Anonymous, Beschreibung und Abbildung des Telegrap/ien, oder 

 der neuerjundenen Fernschreibemaschine in Paris, Leipzig, 1795; 

 Grethe, "Der erste Chappe'sche Telegraph in Paris, Archiv 

 Jiir Post und Telegraphie, 1895, vol. 23, pp. 650-654; Ignace 

 U.J. Chappe, Histoire de la telegraphie, Paris, 1824, 2 vols.; Abbe 

 F. N. M. Moigno, Traite de telegraphie Hectrique, Paris, 1849, 

 pp. 252-258. 



used this telegraph to administer his conquests. In 

 good weather each symbol of a message was carried 

 through the 14 stations between Paris and the Rhine 

 in about 6 minutes. It took about a quarter of an 

 hour for a message to go from the Rhine to Berlin.^ 

 Napoleon wanted mobile telegraph units to assist in 

 his invasion of Russia but this project was never car- 

 ried out. At various times during the first part of 

 the 19th century, optical, pneumatic, hydraulic, and 

 electrical telegraphs were both suggested and invented 

 to compete with this semaphore telegraph; but it was 

 not until mid-century that the semaphore telegraph 

 was finally replaced by the electromagnetic telegraph. 

 The first attempt to use electric current to transmit 

 information resulted directly from the use of the 

 Chappe telegraph. Bavaria was allied with France 



2 Franz Schnabel, Deutsche Geschichte im Neunzehnten Jahr- 

 hundert, Freiburg, 1929-1937 (4 vols.), vol. 3, pp. 391-392. 



PAPER 29: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: II 



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