American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 594
ny of the signalboxes. In Fig. 361 is shown in general outline the apparatus and connections of a centraloffice of this system. The connections for two patrol circuits are shown in the figure. PEARCE AND JONES POLICE TELEGRAPH. 483. It will be understood that as many more circuits as may be… … PEARCE AND JONES POLICE PATROL SYSTEM.—CONNECTIONS. self-Stopping. Ordinarily the telephone t is not in any circuit. Its terminals are con-nected with a wedge p, by means of which it may readily be introduced into eithercircuit, at the spring-jacks, in the well known way. This telephone is inserted…
Telegraph
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