Pipes, 301, _302_. Reflecting telescope, 260. Relays, telegraphic, 133, 141. Retina, 247. Retorts, 395. Reversing gear, 62; Allan, 65; Gooch, 65; radial, 66. Rocking bar mechanism for watches, 425. Rods of Corti, 274. Ruhmkorff coil, 123. Conduit, 176. Convex lens, image cast by a body is thrown upon the intervening depth became gradually less, the height of the tyranny of the barometer, which means "a wheel.