Hawkins electrical guide ... : questions, answers & illustrations : a progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications ; a practical treatise (1914)
Hawkins, N. (Nehemiah), 1833-1928 · New York : T. Audel & Co. · leaf 545
s used in connection with homeblock signals to signify the approach of a train. Ques. What kind of signals are used during the dayand at night? Ans. Flags or metal signals during the day and lights ofvarious color at night. 2,636 HAWKINS ELECTRICITY Disc signals are displayed by movable shutters or… … <<
Electrical engineering
Internet Archive · Brigham Young University · Public Domain Mark 1.0. Free to use for anything.
