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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(guò)］

為了追溯地下電纜系統(tǒng)的歷史，很有必要去回顧電報(bào)的早期發(fā)展。電報(bào)是第一個(gè)把電能商業(yè)化的設(shè)備，同時(shí)地下電纜成為了電報(bào)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(shí)驗(yàn)也在同步進(jìn)行著。很多早期的商業(yè)線路，基本都是以地下的方式設(shè)計(jì)的。這些商業(yè)線路，標(biāo)志著在世界各地，地下電纜都得到了廣泛的應(yīng)用。