Advantages of Morse Code In the modern age, the Morse code is still as relevant as it was in the days of old. Here are the advantages of Morse code. Cheap
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- Telegraphy and longitude[edit]
Cable and Wireless Company[edit]The Eastern Telegraph Company network in 1901 Main article: Cable & Wireless plc Cable & Wireless was a British telecommunications company that traced its origins back to the 1860s, with Sir John Pender as the founder,[79] although the name was only adopted in 1934. It was formed from successive mergers including: The Falmouth, Malta, Gibraltar Telegraph Company The British Indian Submarine Telegraph Company The Marseilles, Algiers and Malta Telegraph Company The Eastern Telegraph Company[80] The Eastern Extension Australasia and China Telegraph Company The Eastern and Associated Telegraph Companies[81] Telegraphy and longitude[edit]Main article § Section: History of longitude § Land surveying and telegraphy. The telegraph was very important for sending time signals to determine longitude, providing greater accuracy than previously available. Longitude was measured by comparing local time (for example local noon occurs when the sun is at its highest above the horizon) with absolute time (a time that is the same for an observer anywhere on earth). If the local times of two places differ by one hour, the difference in longitude between them is 15° (360°/24h). Before telegraphy, absolute time could be obtained from astronomical events, such as eclipses, occultations or lunar distances, or by transporting an accurate clock (a chronometer) from one location to the other. The idea of using the telegraph to transmit a time signal for longitude determination was suggested by François Arago to Samuel Morse in 1837,[82] and the first test of this idea was made by Capt. Wilkes of the U.S. Navy in 1844, over Morse's line between Washington and Baltimore.[83] The method was soon in practical use for longitude determination, in particular by the U.S. Coast Survey, and over longer and longer distances as the telegraph network spread across North America and the world, and as technical developments improved accuracy and productivity[84]: 318–330 [85]: 98–107 The "telegraphic longitude net"[86] soon became worldwide. Transatlantic links between Europe and North America were established in 1866 and 1870. The US Navy extended observations into the West Indies and Central and South America with an additional transatlantic link from South America to Lisbon between 1874 and 1890.[87][88][89][90] British, Russian and US observations created a chain from Europe through Suez, Aden, Madras, Singapore, China and Japan, to Vladivostok, thence to Saint Petersburg and back to Western Europe.[91] Australia was linked to Singapore via Java in 1871[92] and the web circled the globe in 1902 with the connection of Australia and New Zealand to Canada via the All Red Line. The double determination of longitudes from east to west and from west to east agreed within one second of arc (1⁄15 second of time – less than 30 metres).[93] Download 0.84 Mb. Do'stlaringiz bilan baham: |
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