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1847 __ Two-needle Telegraph
George Little (?-?)
Comment : George Little, an American living in London in 1847, obtained a patent for a remarkably simple two-needle telegraph along with a host of other electrical devices, relays, lightning conductors, clocks, batteries and insulators. Only the insulators survived into posterity. From the patent drawings the device was obviously manufactured (they were illustrations not schematics). A substantial pamphlet was produced to promote the patent apparatus. Initially Little was in partnership with Alfred Brett, not, apparently, one of the famous Brett family who organised the cross-Channel cable, but a brandy merchant. After successfully challenging Little’s patent in the Courts during 1851 the Electric Telegraph Company suppressed its use. At this time George Little went on devise an ingenious miniature telegraph receiver using magnetised moving filaments in oil-filled glass tubes instead of needle galvanometers, which he attempted to market in Britain, Europe and America during the 1850s. In July 1852 Little returned to New York and, in the later 1860s, patented his version of an automatic telegraph, which T A Edison in America subsequently perfected – the great man’s first electrical success. (Compiled from various sources)Brett & Little’s Electro-Telegraphic Converser 1847.The first instrument devised by George Little, financed by Henry and Alfred Brett, London brandy distillers. It was the earliest challenge to the Cooke & Wheatstone telegraph with a two needle indicator and a horizontal (left and right) handle to communicate. The Electric Telegraph Company bought the patent in 1851 and suppressed its use.Little’s Telegraph 1849.George Little's second effort at a telegraph. The indicator uses two glass vials each containing a metal filament in oil which moves either left or right using the current reversing buttons on the base. There was also a miniature or pocket-sized version. It was used only experimentally. (Compiled from various sources)Cooke and Wheatstone between 1845 and 1852 at first utilising two-needle telegraphs operated initially by ‘S’-shaped handles, then, and more commonly, by drop handles. It used two-wire circuits, with earth return. The two-needle apparatus was considerably faster in working than the later single-needle device but this was counter-balanced by the cost of instruments and wires. In case of breakages in one or other of the wires the clerks were taught an abbreviated code using one of the two needles on the dial. Its use continued into the late 1870s. [...] The advantages Cook & Wheatstone's two-needle instrument possessed over Bain’s and the American telegraph were stated in 1854; that it did not demand the same skilled hands to wind and adjust the machine and prepare the paper; it was always ready at hand, and only needed attention at long intervals; its disadvantages were, that it did not trace the message, and consequently left no telegraphic record for reference, and it required two wires, while the Bain writer and the American telegraph employed one; the current required to work it was the same as the former, and rather less than the latter. As well as on the Electric, Cooke & Wheatstone’s two-needle telegraph was used between 1852 and 1854 on the circuits of the Submarine Telegraph Company between London, Dover, Calais, Brussels and Paris. The original two-needle code of 1843 had an alphabet of just twenty letters and ten numbers on a single square dial. By 1852 this had been replaced by a twenty-five letter alphabet with no numbers; the numbers were then spelled out as words. At the same time “twin-dials” were introduced, being two single-needle dials set in a single face allowing for economy in manufacture, worked by drop-handled commutators. These dials replaced the original six-inch coils of wire working behind the needles with compact one-inch coils. (Steven Roberts, “Distant Writing - A History of the Telegraph Companies in Britain between 1838 and 1868”, 2010)
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