Telegraph engineering : a manual for practicing telegraph engineers and engineering students (1922)
Hausmann, Erich, 1886- · New York : D. Van Nostrand Company · leaf 288
Fig. 6. 5. Underground Cable In-stallation. — In densely-popu-lated locaHties it is customary to place telegraph and … Fig. 1. other electric cables underground. These cables are notburied in the ground, but are drawn into finished ducts 274 TELEGRAPH ENGINEERING or conduit from one manhole to another. When laid,conduit having a sufficient number of ducts to allowfor future growth is placed in a trench and is…
Telegraph
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