Semaphore Telegraph, or optical telegraph, was the "first practical system of long-distance telegraphic communication" (Bray 35). Typically, it is described as a communications medium which required the use of manual movable arms or closeable apertures mounted in towers (on hilltops) that were in line-of-sight.
Messages Letter by Letter
transmission measured by words per minuted
In 1794, French engineer Claude Chappe invented the semaphore telegraph. Chappe's semaphore had movable arms and handles to operate them.
A "Telegraph Hill" is a site where a semaphore station was installed between London, Deal,and Portsmouth. These semaphore stations were developed by Lord George Murray "using holes closed manually by movable wooden shutters" (Bray 37).
dependence on light disruption by bad weather
The system "may be regarded as a precursor of present-day microwave radio, relay systems which often use hilltop sites" (Bray 37).
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- Bray, John. The Communications Miracle: The Telecommunication Pioneers from Morse to the Information Superhighway. New York: Plenum Press, 1995. or Bray, John. Innovation and the Communications Revolution: from the Victorian pioneers to broadband Internet. London: The Insitutition of Electrical Engineers, 2002. p. 31.
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