![]() ![]() Prior to this invention by Italian physicist Alessandro Giuseppe A. ![]() It was the invention of the battery and the resultant availability of electric charges moving at 186,000 mi (299,460 km) per second (the speed of light) that accomplished this. Advances in electricity would soon put this system out of business. Its shortcomings, however, were its dependence on good weather and its need for a large operating staff. He combined the Greek words tele meaning distance and graphien meaning to write, to define it as writing at a distance. It was Chappe who coined the word telegraph. Their system was successful and soon was duplicated elsewhere in Europe. Together, they could signal all the letters of the French alphabet as well as some numbers. Each tower was equipped with telescopes pointing in either direction, and a cross at its top whose extended arms could each assume seven easily-seen angular positions. The Chappes built a series of two-arm towers between cities. In 1791, French engineer Claude Chappe (1763 – 1805) and his brother Ignace (1760 –1829) invented the semaphore, an optical telegraph system that relayed messages from hilltop to hilltop using telescopes. Visual systems had a greater range than ones that depended on being heard, and they were greatly stimulated by the seventeenth century invention of the telescope. It is also known that Native Americans used signal fires before colonial times and later. 118 BC), recounted a visual code that was used to signal the 24-letter Greek alphabet. ![]() 455 BC) described nine beacon fires used on natural hills that could communicate over 500 mi (805 km), and Greek historian Polybius (c. Drumbeats extended the range of the human voice and are known to have sent messages as have reed pipes and the ram ’s horn. The ancient peoples of China, Egypt, and Greece used smoke signals by day and beacon fires by night. ![]() The earliest forms of sending messages over distances were probably both visual and acoustic. Satellite transmission and high-frequency radio bands are used for international telegraphy. Telegrams and telexes used telegraphy but are rapidly being replaced by facsimile (fax) transmissions through telephone lines. Telephones did not make the telegraph obsolete but rather complemented it for many decades. From its invention until the telephone became a viable system, the telegraph was the standard means of communicating both between and within metropolitan areas in both Europe and the United States. Although it is associated with sending messages via an electric current, the word telegraph was coined to describe an optical system of sending coded messages. A telegraph (also called a teletypewriter, teletype, or TTY ) is any system that transmits encoded information by signal across a distance with the use of an electro-mechanical typewriter. ![]()
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