Electrical telegraph

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An electrical telegraph is a telegraph that uses electrical signals, usually conveyed via telecommunication lines or radio. The electromagnetic telegraph is a device for human-to-human transmission of coded text messages.

The electrical telegraph, or more commonly just 'telegraph', superseded optical semaphore telegraph systems, such as those designed by Claude Chappe for the French military, and Friedrich Clemens Gerke for the Prussian military, thus becoming the first form of electrical telecommunications. In a matter of decades after their creation, electrical telegraph networks permitted people and commerce to almost instantly transmit messages across both continents and oceans, with widespread social and economic impacts.

Contents

History

Early works and messages

From early studies of electricity, electrical phenomena were known to travel with great speed, and many experimenters worked on the application of electricity to communications at a distance.

All the known effects of electricity - such as sparks, electrostatic attraction, chemical changes, electric shocks, and in later more advanced studies, electromagnetism - were applied by various people to the problems of detecting controlled transmissions of electricity at various distances.

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