Henderson, C. Hanford (Charles Hanford), 1861-1941, Woodhull, John F. (John Francis), 1857-1941 · New York, D. Appleton and company · leaf 299
elephone.—Fig. 188 will serve to illustratethe essential features of the telephone. The transmitter,I7, is a box filled with granules of carbon, into which thebattery wires enter. P is the primary circuit of an induc-tion coil. Tapping upon the box, T, or speaking into itscauses the battery current… … Fig. 188.—The telephone.
Physics
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
