First test of the optical telegraph system

Claude Chappe invented the Chappe telegraph in 1792, a system of visual communication using an optical panel to transmit messages between cities. On 2 and 3 March 1792, Chappe tested this system with a trial between the towns of Brûlon and Parcé, a distance of 16 kilometers. The first message sent was 'The National Assembly will reward experiments that are useful to the public.'

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