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In order to trace the history of underground cablesystems, it is necessary to examine the early days of the telegraph [1,2]. Thetelegraph was the first device utilizing electrical energy to become of anycommercial importance and its development necessarily required the use ofunderground construction. Accordingly, experimentation with underground cableswas carried on contemporaneously with the development of the apparatus forsending and receiving signals. Underground construction was planned for most ofthe earliest commercial lines. A number of these early installations are ofconsiderable interest as marking steps in the development of the extensiveunderground power systems in operation around the world.

［appleseden 在 2016-10-30 23:29:24 編輯過］

為了追溯地下電纜系統(tǒng)的歷史，很有必要去回顧電報的早期發(fā)展。電報是第一個把電能商業(yè)化的設備，同時地下電纜成為了電報發(fā)展中的必要環(huán)節(jié)。因此，伴隨著發(fā)送和接收裝置的發(fā)展，地下電纜的實驗也在同步進行著。很多早期的商業(yè)線路，基本都是以地下的方式設計的。這些商業(yè)線路，標志著在世界各地，地下電纜都得到了廣泛的應用。