Thursday, January 14, 2010

The History of the Electric Telegraph and Telegraphy




The electric telegraph is a now outdated communication system that transmitted electric signals over wires from location to location that translated into a message.
The non-electric telegraph was invented by Claude Chappe in 1794. This system was visual and used semaphore, a flag-based alphabet, and depended on a line of sight for communication. The optical telegraph was replaced by the electric telegraph, the focus of this article.
In 1809, a crude telegraph was invented in Bavaria by Samuel Soemmering. He used 35 wires with gold electrodes in water and at the receiving end 2000 feet the message was read by the amount of gas caused by electrolysis. In 1828, the first telegraph in the USA. was invented by Harrison Dyar who sent electrical sparks through chemically treated paper tape to burn dots and dashes.

Electromagnet

In 1825, British inventor William Sturgeon (1783-1850) revealed an invention that laid the foundations for a large scale evolution in electronic communications: the electromagnet. Sturgeon displayed the power of the electromagnet by lifting nine pounds with a seven-ounce piece of iron wrapped with wires through which the current of a single cell battery was sent. However, the true power of the electromagnet was its role in the creation of countless inventions to come.

Three Telegraph Systems Emerge Based on the Electromagnet

In 1830, an American, Joseph Henry (1797-1878), demonstrated the potential of William Sturgeon's electromagnet for long distance communication by sending an electronic current over one mile of wire to activate an electromagnet which caused a bell to strike. In 1837, British physicists, William Cooke and Charles Wheatstone patented the Cooke and Wheatstone telegraph using the same principle of electromagnetism.
However, it was Samuel Morse (1791-1872) that successfully exploited the electromagnet and bettered Joseph Henry's invention. Morse made sketches of a "magnetized magnet" based on Henry's work. Morse invented a telegraph system that was a practical and commercial success.

Samuel Morse

While a professor of arts and design at New York University in 1835, Samuel Morse proved that signals could be transmitted by wire. He used pulses of current to deflect an electromagnet, which moved a marker to produce written codes on a strip of paper - the invention of Morse Code. The following year, the device was modified to emboss the paper with dots and dashes. He gave a public demonstration in 1838, but it was not until five years later that Congress (reflecting public apathy) funded $30,000 to construct an experimental telegraph line from Washington to Baltimore, a distance of 40 miles. Six years later, members of Congress witnessed the sending and receiving of messages over part of the telegraph line. Before the line had reached Baltimore, the Whig party held its national convention there, and on May 1, 1844, nominated Henry Clay. This news was hand-carried to Annapolis Junction (between Washington and Baltimore) where Morse's partner, Alfred Vail, wired it to the Capitol. This was the first news dispatched by electric telegraph.

What Hath God Wrought?

The message, "What hath God wrought?" sent later by "Morse Code" from the old Supreme Court chamber in the United States Capitol to his partner in Baltimore, officially opened the completed line of May 24, 1844. Morse allowed Annie Ellsworth, the young daughter of a friend, to choose the words of the message, and she selected a verse from Numbers XXIII, 23: "What hath God wrought?", which was recorded onto paper tape. Morse's early system produced a paper copy with raised dots and dashes, which were translated later by an operator.

The Telegraph Spreads

Samuel Morse and his associates obtained private funds to extend their line to Philadelphia and New York. Small telegraph companies, meanwhile began functioning in the East, South, and Midwest. Dispatching trains by telegraph started in 1851, the same year Western Union began business. Western Union built its first transcontinental telegraph line in 1861, mainly along railroad rights-of-way. In 1881, the Postal Telegraph System entered the field for economic reasons, and merged with Western Union in 1943.
The original Morse telegraph printed code on tape. However, in the United States the operation developed into sending by key and receiving by ear. A trained Morse operator could transmit 40 to 50 words per minute. Automatic transmission, introduced in 1914, handled more than twice that number. Canadian, Fredick Creed invented a way to convert Morse code to text in 1900 called the Creed Telegraph System.

Multiplex Telegraph, Teleprinters, & Other Advancements

In 1913 Western Union developed multiplexing, which it made possible to transmit eight messages simultaneously over a single wire (four in each direction). Teleprinter machines came into use about 1925. Varioplex, introduced in 1936, enabled a single wire to carry 72 transmissions at the same time (36 in each direction). Two years later Western Union introduced the first of its automatic facsimile devices. In 1959 Western Union inaugurated TELEX, which enables subscribers to the teleprinter service to dial each other directly.

Telephone Rivals the Telegraph

Until 1877, all rapid long-distance communication depended upon the telegraph. That year, a rival technology developed that would again change the face of communication -- the telephone. By 1879, patent litigation between Western Union and the infant telephone system was ended in an agreement that largely separated the two services. Samuel Morse is best known as the inventor of the telegraph, but he is also esteemed for his contributions to American portraiture. His painting is characterized by delicate technique and vigorous honesty and insight into the character of his subjects.

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