History, theory, and practice of the electric telegraph (1866)
Prescott, George B.(George Bartlett),1830-1894 · Boston, Ticknor and Fields · leaf 195
Fig. 72. sixteenth of an inch in diameter; more than one may be placedin the same cable, and from one to six have been included, ac-cording to the multiplicity of correspondences to be transmitted.The wire, or each of the wires if there are more than one, is SUBTERRANEAN AND SUBMARINE LINES. 177…
Telegraph
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