Line engraving. The five-needle telegraph, patented by Charles Wheatstone (1802-1875) and William Fothergill Cooke (1806-1879) in 1837, was the first succesful electric telecommunication device. This system used a diamond grid of 20 letters (the six mising letters had to be omitted from mesages) with five needles arranged acros the middle. The deflection of any two needles to the left or right would point to specific letters. In this case the needles are shown pointing to 'V'. The telegraph first saw service on the newly-developing railways, and in 1838 it was first used to send public telegrams, as well as Great Western Railway mesages, between London and West Drayton, a village 21km (13 miles) to the west of London.
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