By the latter half of the century, most developed nations had created commercial telegraph networks with local telegraph offices in most cities and towns, allowing the public to send messages called telegrams addressed to any person in the country, for a fee.īeginning in 1850, submarine telegraph cables allowed for the first rapid communication between continents. In the 1840s, the electrical telegraph superseded optical telegraph systems, becoming the standard way to send urgent messages. This was built around the signalling block system with signal boxes along the line communicating with their neighbouring boxes by telegraphic sounding of single-stroke bells and three-position needle telegraph instruments. In 1865, the Morse system became the standard for international communication using a modified code developed for German railways.Įlectrical telegraphs were used by the emerging railway companies to develop train control systems, minimizing the chances of trains colliding with each other. The archetype of this category was the Morse system, invented by Samuel Morse in 1838. The second category consists of armature systems in which the current activates a telegraph sounder which makes a click. The first commercial system, and the most widely used needle telegraph, was the Cooke and Wheatstone telegraph, invented in 1837. Early systems used multiple needles requiring multiple wires. The first category consists of needle telegraphs in which a needle pointer is made to move electromagnetically with an electric current sent down the telegraph line. Many different electrical telegraph systems were invented, but the ones that became widespread fit into two broad categories. ![]() The offices were connected by wires, usually supported overhead on utility poles. Text telegraphy consisted of two or more geographically separated stations, called telegraph offices. ![]() Electrical telegraphy can be considered to be the first example of electrical engineering. ![]() It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to communicate text messages quicker than physical transportation. Hughes telegraph, an early (1855) teleprinter built by Siemens and HalskeĮlectrical telegraphs were point-to-point text messaging systems, primarily used from the 1840s until the late 20th century.
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