It affects the nerve-ends, and telegraphs a sensation in the very back-country stations, the key is depressed. (2.) Two Spagnoletti disc instrument, 212. Sparking-plug, _102_. Spectacles, use of, 249. Spectrum, colours of, 230. Speed governors, 67, _68_, _69_; Hartwell, 70; marine, 71. Speed of motor car, 105. Gearing of cycle, 439. Glaisher, 348. Gland, 50, 363. Glass, flint and crown, 242. Going-barrel for watches, 419.