American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 589
mitted by a citizens key.This is accomplished by a device within theon the inside of the inside door, Fig-and, at the same time,a shoit time,just prior to the sending in of the box number bythe break-wheel bw. At the same time, also, thespecial wheel svv is cut out of the circuit, so thatit is… … which he pulls the crank, which, by transmittingthe signal, announces to headquarters his presence at a certain box. An answer THE CHICAGO POLICE PATROL TELEGRAPH SYSTEM. 479 back signal on the bell, within the box, informs him that his report has been receivedand he may proceed on his beat. If the…
Telegraph
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