American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 74
ircuit may be represented, as in Fig. 32, by a line, or wire w, battery b THE MORSE TELEGRAPH SYSTEM. 51 and a galvanometer, g, which is an instrument devised to indicate the presence of auelectric current in a circuit, {see Galvanometers). The source of electromotive force, in this case battery b,… … The course of the circuit is assumed to be from the positive pole of the cell, orbattery b, and thence through the wire w, the galvanometer g, and back, through thebattery, to the positive pole. When key k is down, or closed, as in the figure, thecircuit is completed, and a continuous current…
Telegraph
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