telegraph, term originally applied to any device or system for distant communication by means of visible or audible signals, now commonly restricted to electrically operated devices. Attempts at long-distance communication date back thousands of years (see signaling). As electricity came into greater use, various practical and experimental methods of signaling were tried. A method that came into general use throughout most of the world was based in large part on the work of Samuel F. B. Morse. In Morse telegraphy, an electric circuit is set up, customarily by using only a single overhead wire and employing the earth as the other conductor to complete the circuit. An electromagnet in the receiver is activated by alternately making and breaking the circuit. Reception by sound, with the Morse code signals received as audible clicks, is a swift and reliable method of signaling. The first permanently successful telegraphic cable crossing the Atlantic Ocean was laid in 1866. In 1872, J. B. Stearns of Massachusetts devised a method for "duplex" telegraphy, enabling two messages to be sent over the same wire at the same time. In 1874, Thomas A. Edison invented the "quadruplex" method for the simultaneous transmission of four messages over the same wire. In addition to wires and cables, telegraph messages are now sent by such means as radio waves, microwaves, and communications satellites (see satellite, artificial). Telex is a telegraphy system that transmits and receives messages in printed form. Today telegraphy is rarely used, having been supplanted by the telephone, facsimile machines, and computer electronic mail, among others. Western Union, the American telegraph company whose origins date to 1851, stopped transmitting telegrams in 2006.

Western Union Telegraph Company, enterprise created (1851) to provide telegraphic communications services in the United States. Originally known as the New York and Mississippi Valley Printing Telegraph Company, Western Union (as it was renamed in 1856 after a series of acquisitions) built the nation's first transcontinental telegraph line in 1861. The company briefly entered the telephone field but, after losing a court battle with Bell Telephone in 1879, turned completely to telegraph communications. Western Union's telegraph business grew rapidly, reaching its height (more than 200 million telegrams) in 1929. By 1943, after acquiring Postal Telegraph and some 500 other competitors, Western Union was easily the largest company in its field. During the 1960s, faced with steeply declining telegraph revenues and rising costs, the company moved into a number of other related services, such as time-sharing computer systems, teleprinters, and satellite communications. The Western Union Corp., formed in the 1970s, eventually sold off its communications businesses and emerged in the early 1990s as the New Valley Corp., a banking services and real estate company. Another part of the original company, Western Union Financial Services, became a subsidiary of First Data Corp. in 1995 and now specializes in electronic money transfers and business communications services; it continued to transmit telegrams until 2006.

Electromagnetic communication device. In 1832 Samuel F.B. Morse made sketches of ideas for a system of electric telegraphy, and in 1835 he developed a code to represent letters and numbers (Morse code). In 1837 he was granted a patent on an electromagnetic telegraph that transmitted signals along a wire. That same year British inventors patented a telegraph system that activated five needle pointers that could be made to point to specific letters and numbers on their mounting plate. Public use of Morse's telegraph system began in 1844 and lasted more than 100 years. By the late 20th century the telegraph had been replaced in most applications in developed countries by digital data transmission systems based on computer technology. Seealso Western Union Corp.

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Former U.S. telegraph company and contemporary provider of electronic financial transactions. From its foundation in 1851 as a company formed to build a telegraph line from Buffalo, N.Y., to St. Louis, Mo., in 1856 the expanding business was reorganized as the Western Union Telegraph Co. By the end of 1861 Western Union had built the first transcontinental telegraph line. The company introduced singing telegrams in 1933. Western Union continued to grow, absorbing competitors such as Postal Telegraph Inc. in 1943. As telegraphy was superseded by other methods of telecommunication, Western Union diversified into teletypewriter services, money orders, and mailgrams. It launched the telecommunications satellite Westar 1 in 1974 and was operating five satellites by 1982. In 1988 the company was reorganized as Western Union Corp. to handle money transfers and related services. After declaring bankruptcy in 1993, it sold its financial services arm in 1994 to First Financial Management Corp., and in 1995 that company merged with First Data Corp. The renamed Western Union Financial Services, Inc., became a world leader in electronic (including Internet) transactions.

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