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1846 __ The Sounder - The ‘American Telegraph’
Samuel (Finley Breese) (1791-1872)
Comment : The system patented by S F B Morse in 1846 was commonly called the ‘American Telegraph’ by Government, by the telegraph companies and by the press in Britain during this period. It originally consisted of a ‘key’ to make and break an electrical circuit, a ‘register’ that had an electro-magnetically-controlled point scratch a mark on a mechanically-driven roll of paper, and a ‘relay’ that took the weak line signal and amplified it in a separate local circuit to work the register. The ‘register’ was a substantial piece of equipment requiring a strong current and a clockwork source. It had to be kept wound-up and to be turned on when a message was signalled. In Europe, by 1856 the scratching mechanism was replaced by a sensitive inking device that printed dots and dashes on the tape, and which required far less pressure and electrical current, rendering the local relay unnecessary. Digney in France and Siemens & Halske in Prussia perfected the ‘inker’ or ‘writer’ from an idea by Thomas John, an official of the Austrian k.k. Staatstelegraph, in 1854. This, the ‘key-and-writer’ rather than the ‘key-and-register’, was the working mode of the American telegraph in European service. The reading of the scratch marks on the tape of the original register was in any case difficult and in America operators learned to interpret the movements of the device by its sound. By 1859, much against the wishes of S F B Morse, the sounder or acoustic telegraph [an acoustic receiver, almost universal in the United States from the mid-1850s and familiar to current audiences for cowboy films] was introduced in American service. This was a simple, small electro-magnetic device that clicked in time with the distant key, replacing the old register of 1846 [working the “European Alphabet” acoustically, a variant of the Morse-Vail code]. (Steven Roberts, “Distant Writing - A History of the Telegraph Companies in Britain between 1838 and 1868”, 2010)
Urls : http://distantwriting.co.uk/technicaldetail.aspx (last visited )

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