 内容提要：莫斯科电码中的救难信号SOS（三短三长三短）是如何广为流传，为人所知的。 In 1896, a 24-year-old man in Italy invented the wireless无线的 telegraph. His name was Marconi. Until then, telegraph电报 messages could be sent only between places that were connected by electric wires. Code代码 signals were made by opening and closing the electrical circuit电路. Letters would be "tapped" out using a series of dots and dashes. Marconi's invention made it possible to send messages across the ocean. Until then, ships at sea that needed help had no way to send out distress危难 signals. Starting in 1904, wireless telegraph systems were installed on ships. It was decided that the Morse code letters SOS should be used. They were not picked because SOS stood for "Save Our Ship" as many people believe. They were chosen because it would be easy and quick to tap out three dots, three dashes, and three dots all together in one string (···- - -···). There would be no break between the letters. On August 11, 1909, the Arapahoe was the first American ship to send out an SOS distress call. It was in the Atlantic大西洋的 Ocean and the ship's propeller螺旋桨 had broken. The call was heard on shore and help was quickly sent. A few months later, the Arapaho received an SOS call from another ship and was able to give it assistance援助. Morse code is hardly ever used as a distress call on ships now. Instead, they have mobile移动的 phones, fax machines, and e-mail to send and receive messages. Many ships also have the satellite-based Global Positioning System. It can pick up a ship's exact location and problem instantly立即.
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来自： 昵称70926123 > 《待分类》
