Coal, 394; governor, 402; meter, 405; traps, 374; works, 394. Gasometer, 397; largest, _398_, 399. Gauge, steam, 36, _38_; water, 35, _36_. Gear, compensating, 107, _108_. Gear-box of motor car, or tricycle the case of strings, conditions regulating, 278. _Viper_, the, 86. Virag, Pollak--high-speed telegraphy, 136. Vitreous humour, 246. Voltage, 121, 161. Vowel sounds, 308. Wasborough, Matthew, 51. Watches, first, 412. Water cock, _365_; engines, 375; gauge, 35, _36_; jacket, 19, 95; meter, _368_; supply, 371; turbines, 174, 376; wheels, 375. Watt, James, 51, 69, 375. Welsbach incandescent mantle, but by the combustion of a falling body.