87, 95; reciprocating, 44. Escapement of timepieces, 416; cylinder, _420_; lever, 421, _422_. Ether, 270. Eustachian tube, 276. Eye, human, 246, _247_; self-accommodation of, 248. Expansive working of steam, 55. Cycle, gearing of, 439. Cylinder, hydraulic press, _363_; steam, _49_. Danes, 382. Dead point, 47. De Brouwer stoker, 401. Detector in Chubb lock, 435. Diving-bell, _332_; simple, _333_, _334_. Diving-dress, 335. Direction of current on, 129. Mainspring, invention of, 59. Compound locomotives, 62. Compound microscope, 261. Condenser, marine, 71, _72_; of Ruhmkorff coil, 123. Conduit, 176. Convex lens.