3-028-280 - The Print Collector/Heritage Images

Telegraph diagram and reading-plate of Sir F. Ronald's electric telegraph, 1870. Diagrams of '...the instrument contrived by Mr. Francis Ronalds, in 1816, for transmitting messages by the electric telegraph which he constructed, with a length of eight miles of wire, in his garden at Hammersmith. Hence it is evident," says the inventor, "that when the wire was charged by the machine at either end the electrometers at both ends diverged; when it was discharged suddenly at either station they both collapsed at the same instant; and if it was discharged at the moment when a given letter, figure, and sign on the lower plate (fig. 3) of one clock, appeared in view through the aperture, the same figure, letter, and sign appeared also in view at the other clock, so that, by such discharges of the wire at one station, and by noting down the letters, figures, or signs in view at the other, any required words could be spelt, or figures transmitted"...In the memoir of Sir Francis Ronalds...[elsewhere in this journal], allusion is made to the supercilious rejection of his electric telegraph by the Lords of the Admiralty, twenty years before the date of Messrs. Cook and Wheatstone's patent'. From "Illustrated London News", 1870.