American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 383
C 11 … has a resistance, under a pressure of 8 lbs., of about 2 ohms. The two circuits employed in this system are practically separate from eachother. When the apparatus is at rest the projections e e on the rod r of the transmitter(Fig 243) press equally against their respective discs. Consequently an…
Telegraph
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