American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 66
achine may be con-sidered as the equivalent of a gravity battery of very low resistance, out of whicha large number of wires are fed.* In the New York plant there are 16 machinesfurnishing eight grades of negative and positive potential, namely, 50, 70, 90, no,200, 250, 275 and 300 volts,… … myes 7b JyCres 48 DYNAMO MACHINES.
Telegraph
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