Sunday 17 August 2014

Telegraph

Telegraph
The cities and countries and continents of the earth are connected by thousands of miles of wire and cable, along which messages are sent with nearly the speed of light. This vast communication network depends upon the electric telegraph, a device first made practical by an American inventor. But, like most inventions, the practical telegraph was made possible by a long history of experimentation and discovery. Let us first take note of some of the pioneers in this field.

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