Electric Telegraph
By Rochelle Forrester
Ó All Rights Reserved
Publication Date 2006
The use of electricity for the communication of messages began with the telegraph. An electric current is able to flow along a wire and arrive almost instantaneously at its destination. The first known suggestion for an electric telegraph was made in 1753 by Charles Morrison, a Scottish surgeon. It involved 26 wires, one for each letter of the alphabet, which could carry a discharge of electricity and attract a piece of paper representing a letter to an electrified ball where the message was to be received. In 1804 Francisco Salva in Spain, using an electric battery and a similar system of multiple wires as was proposed by Morrison sent messages up to a kilometer, while in 1812 Dr Samuel von Sommering using improved batteries sent messages for 2 miles. In 1832 a system using one to six wires was created by Baron Pawel Schulling in Berlin with needles hanging over coils being moved by the current to indicate letters. William Cooke and Professor Charles Wheatstone received a patent in 1837 in England for a telegraph of 5 wires connected to needles which moved to indicate letters.
A system using a single wire was patented in 1838 by Samuel Morse. Morse realized a message could be sent by interrupting the current in such a way that the interruptions constituted a sign. The sign or a combination of signs could represent letters of the alphabet so a message could be sent. Samuel Morse invented this system, known as Morse code, but an instrument for sending and receiving the code was also needed.
The first instrument Morse came up with involved an electro-magnet with a pendulum. When Morse made or broke the current the electro-magnet moved the pendulum which was attached to a pencil which marked a paper tape. The marks on the tape were a series of zigzag lines which represented the letters of the alphabet. The instrument was eventually improved by replacing the pendulum with a clockwork mechanism and the zigzag lines were replaced with the dots and dashes of Morse code. The current from the system was initially to weak to send a message for any great distance so Morse invented the relay. This was an electro-magnet that could close the circuit on a new line and add more power to send the current further.
After some difficulties Morse was able to set up the first working telegraph in 1844 between Washington and Baltimore. By 1851 a submarine cable was placed across the English Channel and in 1866 a trans–Atlantic cable was laid. In America the Western Union Telegraph Company placed telegraph lines across America and soon every railway station had a telegraph office to control the movement of trains.
The telegraph continued to be improved when in 1855 Professor David Hughes invented a printing telegraph using a keyboard into which the letters were typed and the massage was printed out where it was received. Duplex telegraphy which allowed two messages to be sent over the same line at the same time was invented by J. B. Stearns and patented in 1872. Transmission speeds were increased by the introduction of a punched tape system which allowed the transmission of 75-100 words per minute. Morse’s original telegraph of 1838 could only transmit at up to 10 words per minute.
The telegraph was to vastly speed up the spread of news. In 1776 it took seven weeks for a sailing ship to bring word to London of America’s Declaration of Independence. During the Crimean War word reached London by telegraph of the death of the Russian Czar in St Petersburg on the same day he died. The telegraph revolutionized diplomacy with governments being able to have continued and immediate contact with their diplomats abroad. Instructions could be sent and reports received without any time delay, although there was always the risk of interception by unauthorized persons. The Zimmerman telegram, from the German government to Mexico, was decoded by the British and published by the Americans and was one of the events leading to American involvement in World War I.
Public use of the telegraph system grew, so by 1870 it cost a shilling to send a 20 word message anywhere in Great Britain. Ninety million telegrams a year were being sent by the end of the 19th century. In America a telegraph office was available in almost every small town. However by 1918 the telegraph system was of declining importance due to the development of the telephone network.
The electric telegraph could never have existed at all but for the ability of an electric current to travel along a wire and our ability to send and control the current. If metallic wires were not able to conduct electricity or if we were unable to control the electricity through insulating materials, there would be no electric telegraph. The telegraph could not have been developed until after people learnt how to create and control an electric current. This required the invention of the battery and Morse’s invention of the relay which allowed the current to travel long distances. The sending and receiving instruments required the earlier invention of the electro-magnet. Consequentially, the telegraph could only have been invented after the invention of the battery, the relay and the electro-magnet all of which were dependent upon prior discoveries made by scientists engaged in research on electricity and magnetism. The telegraph provided an improved method for meeting the human need for long distance communication and its arrival in the mid 19th century was the culmination of a series of logical developments that lead inevitably to the invention of the telegraph. The existence of electrons and the human ability to create and control an electric current to produce the electric telegraph shows how the structure of the universe or nature has a significant effect on human social and cultural history.