Modern practice of the electric telegraph. A handbook for electricians and operators (1872)
Pope, Frank L. (Franklin Leonard), 1840-1895 · New York : D. Van Nostrand · leaf 16
t 154 Measures of Resistance 154 Strain of Suspended Wires 154 Index 157 MODERN PEACTICE or THS ELECTRIC TELEGRAPH. CHAPTER I. ORIGIN OP THE ELECTRIC CURRENT. GALVANIC BATTERIES. 1. SIMPLE GALVANIC CIRCUIT.—If two plates of dif-ferent metals, such as copper and zinc for example, areimmersed in a… … current of electricity will pass from the copper to thezinc through the connecting wire, and from the zinc tothe copper through the liquid, as indicated by thearrows in the figure. If the metallic communication beinterrupted, or the circuit, as it is termed, broken, thecurrent at once ceases, but…
Telegraph
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