375. Window, oval, in ear, 272; round, in ear, 272; round, in ear, 272. Wireless telegraphy, 137; advance of, 145; receiver, 140, 141; syntonic, 143; transmitter, 138, _139_. Yale lock, 436. Combustion, 26, 393; perfect, 28. Compensating gear, 107, _108_. Gear-box of motor car, 95, _97_. Clarionet, 308. Clock, first weight-driven, 412; water, 410. Clutch of motor cars, 109. Siphon, _351_. Slide-valve, 49, 50, 51; setting of, 53. Edison, Thomas, 310. Edison-Bell phonograph, 310. Electricity, current, 115; forms of, 113; nature of.