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In 1809, Richard Trevithick brought to London the latest wonder of the country's mining areas, an iron wagon-way upon which a steam locomotive ran. At Euston Square in London, he built a round track within a wooden fence and charged one shilling for the ride. In 1825, the first passenger train to go anywhere ran between Stockton and Darlington. The railway age began. Between 1833 and 1843 money was raised to build 2300 miles of railway in the UK. Early railways were only single-track, one track was shared for both ways, which necessitated for the first time instantaneous signaling methods. One of the many who can lay claim to having invented the telegraph, Edward Davy, saw this clearly. In 1838 he wrote: The numerous accidents which have occurred on railways seem to call for a remedy of some kind; and when future improvements shall have augmented the speed of railway traveling to a velocity which cannot at present be deemed safe, then every aid which science can afford must be called in to promote this object. Now, there is a contrivance by which, at every station along the railway line, it may be seen, by inspection of a dial, what is the exact situation of the engines running, either towards or from that station and at what speeds they are traveling. Here then is a real and pressing supervening necessity -- railway safety. And here we are back again to the reality that technology was based on a social need. Also the history of telegraphy offers a clear example of how one technology, in this case the railways, creates a supervening necessity for another, the telegraph. The word telegraphy comes from Greek. "Tele" means distant and "graphein" to write. So the meaning is writing at a distance The first telegraph wires did indeed run beside railway tracks and were used for operational purposes. In the year 1836 a young Englishman named William Fothergill Cooke was studying anatomy at University of Heidelberg, Germany. During a physics lecture, he saw a needle telegraph for the first time. Although Cooke had no knowledge in electronics he recognized the chance of this invention for the future. He returned from studying and began constructing and improving an electrical telegraph. Within three weeks he had designed his own. During this time the English physicist Charles Wheatstone was experimenting with electricity at King’s College, London. There he made his famous determination of the propagation velocity of electricity. Wheatstone showed that all the effects possible with a short wire could also be produced by a long one, and that the results were to all practical purposes instantaneous. By June 1836, he had demonstrated how this technology could be turned into a telegraph. |