Sandhurst, Phillip T, Mueller, A. M. J · Philadelphia ; and Chicago : P.W. Ziegler · leaf 434
6. 398 of signal most universally adopted, proving so superior to all other kinds as to rapidly replace them. When the arm was thrown out at right angles to the post, it signified danger; when hanging ver¬ tically, it denoted safety; and when inclined at an angle of forty-five degrees, it expressed… … RAILWAY SIGNALS. and those on the other T'tjf. 1. side to trains in the other direction. The arms were painted red on the side next to the approaching trains they were intended to govern, and white on the other side, so as to appear less prominent and avoid confusion. Lamps were attached to the…
Centennial Exhibition (1876 : Philadelphia, Pa.) · Decorative arts · Arts · Machinery · Arts, Modern
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.