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The electrical telegraph is a telegraph that uses electric signals. The electromagnetic telegraph is a device for human-to-human transmission of coded text messages over wire. Electrical phenomena were known from the early history of investigation of electricity to travel with great speed, and many experimenters worked on the problem of applying electricity to communications. All the known effects of electricity - such as sparks, electrostatic attraction, chemical changes, electric shocks, and (later) electromagnetic effects - were applied by various people to the problem of detecting controlled transmission of electricity at a distance. In 1746 the French scientist and abbé Jean-Antoine Nollet gathered about two hundred monks into a circle about a mile (a little over a kilometer) in circumference, with pieces of iron wire connecting them and discharged a battery of Leyden jars through them; he observed that each man reacted at substantially the same time to the electric shock, showing the speed of propagation to be very high. [1][2] In 1753 an anonymous writer in the Scots Magazine suggested an electrostatic telegraph, with one wire for each letter of the alphabet - a message could be transmitted by connecting wires in turn to an electrostatic machine, and observing the deflection of pith balls at the far end. [3] While this scheme was eventually demonstrated experimentally in Europe, it was never developed into a useful communication system. At first, they used the telegraph to coordinate time, but soon they developed other signals; finally, their own alphabet. It was not binary, but based on four amplitudes of the needle. Gauss was convinced that this communication would be a help to his kingdom's towns.
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