How Does the Telegraph Work?

By Edwin Thomas

What is Meant by the Word "Telegraph?"

The term "telegraph" commonly refers to a long-distance communication system where messages are carried by electrical signals on wires. Wireless telegraphy or radiotelegraphy, which does not use wires, are rarely meant when a person refers to the telegraph and are not a part of the popular conception of the device.


The telegraph is a device that uses electrical pulses to transmit coded messages through a wire to a receiver, where the message is then decoded. It cannot carry voices or other data and relies entirely upon pulse coding for content. The most famous code is the Morse Code.


The first prototypes for the telegraph were invented and tested by Carl Gauss and Wilhelm Weber in the 1830s. Several other men concurrently and independently experimented with electrical telegraphy, including the Baron Schilling von Calstatt and Dr. David Alter. The first commercial telegraph was built in Britain in 1837, but the technology did not really take off until after Samuel Morse perfected his model in the late 1830s.