Triumphs and wonders of the 19th century, the true mirror of a phenomenal era, a volume of original, entertaining and instructive historic and descriptive writings, showing the many and marvellous achievements which distinguish an hundred years of material, intellectual, social and moral progress .. . e, so useful to civili-zation, so commercially valuable, so fullof possibilities, as telegraphy, could notremain at rest. Everywhere it stim-ulated to improvement and new inven-tion and discovery ; and as the centuryprogressed, it witnessed in steady succes-sion the wonders of what became knownas
Triumphs and wonders of the 19th century, the true mirror of a phenomenal era, a volume of original, entertaining and instructive historic and descriptive writings, showing the many and marvellous achievements which distinguish an hundred years of material, intellectual, social and moral progress .. . e, so useful to civili-zation, so commercially valuable, so fullof possibilities, as telegraphy, could notremain at rest. Everywhere it stim-ulated to improvement and new inven-tion and discovery ; and as the centuryprogressed, it witnessed in steady succes-sion the wonders of what became knownas duplex telegraphy, that is, the send-ing of different messages over the samewire at the same time. Again, thecentury witnessed the invention ofquadruplex telegraphy, that is, the send-ing of four separate messages over thesame wire, two in one direction andtwo in another. This was followed by cyrus ^v. field. the invention of Grays harmonic sys-tem, by means of which a number of messages greater than four are trans-mitted at the same time over the same wire; and this again by Delaneyssynchronous multiplex system, by means of which as many as 72 separatemessages have been sent over the same wire at the same time, either all inone direction, or some in one direction and the rest in an WONDERS OF ELECTRICITY 29 For a time successful telegraphy was limited to overland spaces, the conduct-ors or wires, consisting of iron or copper, being insulated where they passedthe supporting poles. In the cities, supporting poles proved to be unsightlyand dangerous, and they were succeeded by underground conduits carryinginsulated wires. In 1839, we read of what may be reckoned the first success-ful experiment in telegraphing under water by means of an insulated wire, orcable, as a conductor. The experiment was tried at Calcutta, and under theriver Hugli. In 1842, Morse experimented at New York with an under-watercable, and showed that a successful submarine telegraphy was practical.
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Keywords: ., bookcentury1800, bookdecade1890, bookidtri, booksubjectinventions
