Robison's Manual of radio telegraphy and telephony for the use of naval electricians (1918)
Robison, S. S. (Samuel Shelburne), b. 1867, United States Naval Institute, Todd, David Wooster, Hooper, Stanford Caldwell · Annapolis, Md. : The United States Naval Institute · leaf 50
ir, con-sist of to-and-fro movements parallel to the direction of the waves, thelatter consisting of alternating conditions of compression and rarefactionof the air. The movement of the particles in ether waves is at right angles tothe direction of propagation of the wave, and the electric and… … Fig. 18. When one particle of a substance is displaced or made to vibrate, itinduces its neighbors to follow it, and starts them to vibrating in thesame periods but in different phases, each particle starting to vibrate(passing the word, so to speak) at a definite interval of time after theone next…
