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 437
D-4D-2D-3 D-5 … 30° 20° 10° 0° 10° 20° 30* 20° 10° 0° 10° 20 Figs. 3,475 to 3,478.—Frosted incandescent lamps with holophane reflectors and curves showingcandle power distribution. of one foot candle. This unit is known as the lumen; when alamp is capable of illuminating 400 sq. ft. with an average in-tensity of…
Electrical engineering
Internet Archive · Brigham Young University · Public Domain Mark 1.0. Free to use for anything.
