Electrical engineer's pocket-book: a hand-book of useful data for electricians and electrical engineers (1901)
Foster, Horatio A. (Horatio Alvah), 1858-1913 · New York, D. Van Nostrand co.; London, E.& F.N. Spon, ltd. · leaf 447
re and incandescent lamps be-hind a red glass disk. This makes the signal visible both night and day.This semaphore stays set until he reaches the switch ahead ; then the con-ductor opens the circuit which sets the track behind him to safety. If onreaching the switch he finds the semaphore is set… … the conductors of cars passing it at the switches, and the signal systems forcars operating in opposite direction are entirely independent. In each
Electrical engineering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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