Chappe telegraph
By the mid 19th century, the network spanned several hundred kilometres and covered most major French cities as well as Venice, Mainz and Amsterdam.
This problem was particularly pressing in France at the height of the French Revolution, as the country was surrounded by the hostile forces of Britain, Austria, Prussia and the Netherlands.
In this context, France would obtain strategic advantage if, unlike its enemies, it had a rapid system of reliable communication.
It continued to be used for decades, but its decline began when the first electric telegraph line, based on International Morse code, was set up in 1845.
[10] In 1791, Chappe conceived a project that was to put "the government in a position to transmit its orders over a great distance in the least possible time".
[3] Chappe found experimentally that the angle of the moving pieces of the telegraph was easier to discern accurately at a distance than other characteristics of the towers or other sources of signal.
"[12][13] On 1 April a report vaunting the military use of the telegraph was presented to the National Convention on behalf of the Committees for Public Instruction and War.
On 12 July 1793 a successful first test was carried out over a distance of 26 km, between Ménilmontant, Écouen and Saint-Martin-du-Tertre (in the Val-d'Oise, near Paris).
After a convincing presentation by Joseph Lakanal in support of the project, the National Convention approved the construction of the Paris-Lille telegraph line on 4 August 1793.
[16]The first Chappe telegraph line was a series of towers linking Paris and Lille, a distance of 230 kilometres.
[18] The network was also extended in Europe as far as Amsterdam, Mainz and Venice,[18] and in North Africa, where it covered Algeria (Algiers-Oran and Algiers-Constantine in 1853) and Tunisia (Tunis-La Goulette and Tunis-Mohamedia in 1848–1849).
This workshop specialised in the manufacture of telegraphs and other machines and was located at 882, passage du Désir, faubourg Saint-Denis in what is now the 10th arrondissement of Paris.
Between 1834 and 1836, the telegraph was used by two Bordeaux businessmen, the brothers François and Joseph Blanc, to receive information on Paris Stock Exchange annuity prices before anyone else.
The use was discovered in 1836 and the two brothers spent time in jail awaiting trial but were ultimately found not guilty because there was no law against this behaviour, although they did have to pay a fine for bribing some of the telegraph operators.
In several instances, the local telegraphs were destroyed during popular uprisings,[25] possibly due to suspicions of witchcraft, but more probably in order to hinder government communications.
[26] Many French writers of the time featured the telegraph in their writings (Hugo, Dumas, Chateaubriand, Stendhal, Flaubert).
Victor Hugo described his horror at discovering, while traveling in Normandy in 1836, that the statue of the Archangel on the pinnacle of the steeple of the abbatial church of Mont Saint Michel had been replaced by a Chappe telegraph.
