1826 __ Electrolytic telegraph
‣ Comment : Harrison Gray Dyar, of New York, devised a telegraph in which the spark was made to stain the signals on moist litmus paper by decomposing nitric acid; but he had to abandon his experiments in Long Island and fly the country, because of a writ which charged him with a conspiracy for carrying on secret communication. In 1830 Hubert Recy published an account of a system of Teletatodydaxie, by which the electric spark was to ignite alcohol and indicate the signals of a code. (John Munro) — Alfred Munroe in Concord and the Telegraph records that Dyar and his brother Joseph were interested in the newly developed technology of electricity. They came up with the idea of transmitting a message over electrical wire. Dyar experimented and finally concluded that he had discovered how a message could be transmitted over a single wire. In 1826 he and his brother laid a wire line along the "Causeway", later called Lowell Road and the Red Bridge Road, that proved the technique viable. According to Colonel William Whiting of Concord, the telegraph wire was strung from the trees along the Red Bridge Road over the Concord River at Hunt’s Bridge and went all the way to Curtis’s residence. Dyar used apothecary vial jars as glass insulators for the bare iron wire. Dyar erected the first telegraph line and dispatched over it the first telegraph message ever sent in America. — as determined by Levi Woodbury of the Supreme Court of the United States. Dyar had used over half a mile of bare electrical wire to transmit the message. He employed mechanical and electrical means that Samuel Morse used many years later for the telegraph system he patented in 1847. The author Munroe explains that Dyar made his telegraph line at least eighteen years before the actual materialization of the first practical Morse telegraph line that was made between Washington, D.C., and Baltimore, Maryland. According to Munroe it was Dyar, not Morse, who erected the first real telegraph line at the race track in Long Island in 1826 and dispatched the first message ever sent. This was years prior to the joint patent of electric telegraphy by William Fothergill Cooke and Charles Wheatstone taken out in 1837 in England. Alfred Munroe writes in his book "Concord and the Telegraph", This may seem strange to most of our readers. The credit of this great discovery has been generally conceded to Professor Morse, but the latter deserves credit only for combining and applying the discoveries of others. Dyar had erected his telegraph line some six years before Morse even began his investigation on telegraphy and some ten years before he began to talk about the subject. Dyar recorded the sparks generated by the electrical current of his telegraph on a ribbon of moistened litmus paper on a spool that revolved mechanically by a clockwork apparatus. The nitric acid that was formed on the litmus paper by the action of the electricity left appropriate legible small red marks for designated letters. Dyar’s method was of frictional electrolytic nature where Morse’s was an electromagnetic usage. Dyar’s early experiments using this method worked quite well. In fact his experiments proved his theory would work and impressed several investors. He was able to get an advanced loan in New-York to run a line at the Long Island race-course in 1827. Dyar then proposed to string a wire across New Jersey from New York to Philadelphia. However, the New Jersey legislature was skeptical on the issue because of security reasons. They even condemned Dyar as being dangerous because they thought he was some kind of a "wizard." They refused permission for this experiment of Dyar's because of fear of sending secret communications in advance of the mail. There is an argument amongst historians that Morse got several of Dyar’s plans for the telegraph from him. Morse married the sister of one of Dyar’s associates named Charles Walker. Walker had worked with Dyar on the telegraph and had retained many of Dyar’s sketches. Historians speculate that either Charles Walker or his sister (Lucretia Pickering Walker) might well have shown those sketches to Morse. One idea supposedly "borrowed" was that Dyar used batteries and had the idea of sending electric impulses along a single wire. Dyar also had the idea of spacing the sparks in such a way as to form an alphabetic code and developed out this code years before Morse developed his Morse Code. Dyar moved to Paris because of so much opposition to his telegraph technology. (Compiled from various sources)
‣ French comment : A peu près à l'époque où Ronalds expérimentait en Angleterre, un certain Harrisson Gray Dyar se serait aussi occupé de la télégraphie électrostatique en Amérique. D'après les lettres publiées seulement en 1872 par les journaux américains ["Zetsche-Geschichte der elecktrischen Telegraphie", p. 40] Dyar aurait construit en Amérique la première ligne télégraphique. Cette ligne aurait été établie de 1826 à 1828 à Long Island sur la place de l'Union, elle était en fil de fer porté sur des poteaux avec des isolateurs en verre, et Dyar aurait opéré sur cette ligne avec l'électricité statique. Faisant agir l'étincelle sur une plaque mobile recouverte de papier de tournesol, il aurait produit par la décoloration du papier des points et des traits formant un alphabet. Ces expériences réussirent, paraît-il, si bien que Dyar et ses parents résolurent de construire une ligne de New York à Philadelphie ; mais des querelles avec ses parents, des procès et diverses autres difficultés l'obligèrent de quitter l'Amérique ; il se rendit à Rhode Island, puis en France en 1831 et ne retourna en Amérique qu'en 1858. Dyar aurait donc été le premier à combiner un alphabet composé de points et de traits. La priorité sur ce point a cependant été réclamée par Swaim dans un livre paru en 1829 à Philadelphie sous le titre de "The Mural diagraph" et dans une communication insérée aux compte-rendus de l'Académie des Sciences, séance du 27 novembre 1865. (Auguste Guerout, "L'Historique de la télégraphie électrique", 1883)
‣ Source : Guerout, Auguste (1883), "L'Historique de la télégraphie électrique", In "La Lumière Électrique — Journal Universel d'Électricité", 1e série, vol. 8, n°1-17, 1883, Paris : Union des syndicats de l'électricité,3 mars, No. 9, pp. 257-264.
‣ Urls : http://www.worldwideschool.org/library/books/tech/engineering/HeroesoftheTelegraph/chap1.html (last visited ) http://cnum.cnam.fr/CGI/fpage.cgi?P84.8/265/100/572/0/0 (last visited ) http://chestofbooks.com/crafts/scientific-american/sup2/The-History-Of-The-Electric-Telegraph-Part-5.html (last visited )
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