Electrical telegraph

early system for transmitting text over wires

An electric telegraph is an apparatus, or a process, for communicating messages rapidly between distant telegraph stations, by means of signals transmitted over telegraph wires by electrical propagation. Now technologically obsolete, electric telegraphy was used from the 1840s to the mid 20th century. At the sending station, the telegraph operator read the message and appropriately manipulated switches connecting a source of current to the telegraph wires. At the receiving station, the current activated electromagnets which moved indicators, providing either audible or visual indications so that the receiving telegraph operator could record the text of the message.

Quotes

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  • The military played a significant role in the application of line telegraphy, not only in providing funds for development but also in testing the new ideas in the rigorous environment of military campaigns.
  • Let me remind you that this great country was virtually created one hundred years ago by two inventions. Without them, the United States was impossible, with them, it was inevitable. Those inventions were, of course, the railroad and the electric telegraph.
    Today we are seeing, on a global scale, an almost exact parallel to that situation. What the railroads and the telegraph did here a century ago, the jets and communication satellites are doing now to all the world.
  • ... Few persons, probably, even among ornithologists realize what an enormous number of birds are killed by flying against these wires, which now form a murderous net-work over the greater part of the country. Until recently, I had myself no adequate idea of the destruction that is so quietly, insidiously, and uninterruptedly accomplished. My observations do not enable me to form even an approximate estimate of the annual mortality, and I suppose we shall never possess accurate data; but I am satisfied that many hundred thousand birds are yearly killed by the telegraph.
  • Sir James Anderson and his crew on the ship Great Eastern attempted to lay down the second transatlantic cable in 1865, starting in the Irish island of Valentia. After about 1,062 miles of cable were laid down under the ocean, the cable snapped at the stern of the ship, halting the mission A second attempt was successfully made by the Great Eastern in the following year. On this journey, the crew also retrieved the lost end of the first cable and reconnected it to its original end. By the end of 1866, North America and Europe had two operating cables for telegraphic communications. Telegrams could be transmitted between North America and Europe at the average rate of 0.1 words per minute and at the cost of 10 dollars per page.
    • Sara L. Darella, "Transatlantic Cable". Technical Innovation in American History: An Encyclopedia of Science and Technology. Volume One: Colonial America to 1865, edited by Rosanne Welch & Peg A. Lamphier. ABC-CLIO. 22 February 2019. p. 302. ISBN 9781610690942. 
  • If it be asked what telegraphic system is specifically announced as the most developed and extended throughout the world, the answer would seem to be definitely and summarily given in the proceedings of the International Telegraphic Convention held in Paris in March, 1865, composed of the representatives of twenty of the principal nations of Europe, assembled for the special purpose of examining the various projects, in order to adopt a uniform system, and to regulate international telegraphy for their common benefit. They thus decree in their third article; "L'appareil Morse reste provisoirement adopté pour le service des fils internationaux." Concise as is this announcement, as the result of their deliberations, it proclaims that the Morse system—an American system—is preferred for special international service throughout Europe.
  • ... Gauss and Weber developed an electrical two wires telegraph in 1833 for the synchronisation of observations and tested the transmission of words through an elaborate code (Stevens et al. 1838). Their scientific breakthrough led to the first commercial patent by Wheatstone in 1837 for a five wires telegraph leading immediately to the exploitation of lines between London, Liverpool, Manchester and Birmingham along the new railroad network. This telegraph was using a code able to transmit 20 letters, the other ones having to be omitted. The continental testing of this system in 1840 involved the Director of the Royal Observatory of Belgium, Quetelet and Gauss. The scientific objective being network science coordinating magnetic observatories (Quetelet, 1840). Similar developments in the United States led Morse to design a stable telegraph with a coding system able to transmit many more characters which the US Supreme Court recognized in 1854 as the only patented telegraph system.
  • During the voyage of the packet ship Sully from Havre to New York, in October, 1832, a conversation arose one day in the cabin upon electricity and magnetism. Dr. Charles T. Jackson, of Boston, described an experiment recently made in Paris with an electro-magnet, by means of which elec­tricity had been transmitted through a great length of wire, arranged in circles around the walls of a large apartment. The transmission had been instantaneous, and it seemed as though the flight of electricity was too rapid to be measured. Among the group of passengers no one listened more attentively to Dr. Jackson's recital than a New York artist, named Samuel Finley Breece Morse, who was returning from a three years' residence in Europe, whither he had gone for improve­ment in his art. ...
    "Why," said he, when the doctor had finished, "if that is so, and the presence of electricity could be made visible in any desired part of the circuit, I see no reason why intelli­gence might not be transmitted instantaneously by electric­ity."
    "How convenient it would be," added one of the passen­gers, "if we could send news in that manner."
    "Why can't we?" asked Morse, fascinated by the idea.
    From that hour the subject occupied his thoughts, and he began to exercise his Yankee ingenuity in devising the requisite apparatus.
  • Every day the telegraph lines over the whole country cease work for a short time for the passage of a signal which is sent out from the Observatory at Greenwich exactly at 9 a.m. At the Observatory there is a Standard Clock, and that Standard Clock is the Earth itself. The sky is the dial. Its figures are the stars, and the line of sight of a telescope is the hand which points the hours.
  • At this time ambassadors remained essential due to the slowness of communications. It could take a month for a letter to travel from London to St. Petersburg; in 1822 the record for an urgent dispatch to Vienna was one week. But in the 1840s and 1850s railways started to spread across the Continent, while steamships dramatically reduced the duration of sea voyages. After the introduction of the electric telegraph in the 1870s, ciphered telegrams replaced written dispatches for urgent business. Now that messages could be sent and answered within hours, the embassies in far-flung capitals could be subject to daily supervision. In 1904 the British diplomat Sir Francis Bertie complained that an ambassador had been reduced to the status of a “damned marionette,” with the Foreign Office pulling the wires.
    • David Reynolds, Summits: Six Meetings that Changed the Twentieth Century (2007), p. 21
  • Tous ceux qui se sont occupés de l'application pratique de la télégraphie électrique s'accordent facilement sur ce point, savoir, que l'immense majorité des perturbations sont sujets aux télégraphes électriques proviennent des variations dans l'intensité des courants employés. La cause des variations réside, soit dans la source des courants, soit dans les conditions variables du circuit conducteur. La première de ces causes peut être éliminée en faisant usage de sources constantes. Je me contente d'observer à cet égard que je donne la préférence à la pile de Daniell.
  • (All those who have been concerned with the practical application of electrical telegraphy readily agree on this point, namely, that the immense majority of the disturbances which affect electrical telegraphs arise from variations in the intensity of the currents employed. The cause of the variations lies either in the source of the currents or in the varying conditions of the conductor circuit. The first of these causes can be eliminated by making use of constant sources. I am content, in this regard, to observe that I give preference to the Daniell cell.)
  • ... once, after I came to Fort Sedgwick, the wires were said to be "down," and no communication could be had with other posts in the upper country. It was feared that the Indians had been tampering with the wires, and torn them down. But the operators went out under an escort of soldiers to see what the difficulty was. They came back again in a couple of days, and reported that the Indians had not meddled with the wires at all. But it seemed that some buffaloes in a large drove had taken the privilege of scratching their rumps against the poles, and thus tore them down; and getting their horns entangled in the wires, the wild creatures had carried off about four miles of telegraph-wire!
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