Ternant, A. L. (Alcide Ludovic), 1832-1884 · London ; New York : G. Routledge and Sons · leaf 253
TELEGRAPHIC APPARATUS. 235 same time contact is made at E with the battery P, and the current flows through the line to the distant station. It is often necessary, in very long overhead lines, and with submarine cables, to have recourse to compensation currents, which are made to destroy the… … Fig. 168. Office, and is very useful on certain overhead and submarine lines. The line wire is connected with 3, the earth, and one end of the relay coil with 7, and the other end with 4. The positive pole of the battery is at c, and the negative at z ; l, l ' are two levers insulated from each…
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