A dictionary of electrical words, terms and phrases (1898)
Houston, Edwin J. (Edwin James), 1847-1914 · New York, The W. J. Johnston company · leaf 445
ack is clear,and that the train may safely enter the block itgoverns. Position No. 3, which is used in the permissiveblock system, only signifies caution, and permitsthe train to cautiously enter the block and lookout for further signals. The semaphore arm consists of a light woodenarm, 11 inches… … Fig. 4b4- piSemaphore Signal—Permissive System. operated as follows, viz.: in the absolute system,the semaphore arm A B, pivoted at A, bears atits shorter end a disc or lens of red glass R, and,in the permissive system, below this another discor lens of green glass G. An oil lantern, pro-vided with…
Electricity · Electrical engineering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
