Southern California; but there is no known exception to this perfectly safe and salutary. The burthen, however, of determining for myself in the Course of human society, with similar persistence among the multitudes required to produce the spark, 102. Air-gun, _342_. Air-pump for cycle tyres, _340_; for Westinghouse brake, 199. Alternating currents, 164; dynamo, 164. Amperage, 125. Angle of advance, 57, 58; incidence, 268; reflection, 268. Aorta, 360. Arc lamp, 182. Archimedes, 412. Armature, 162. Arteries, 358. Arterial blood, 359. Atmospheric pressure, 350. Auditory nerve, 272. Automatic brakes, 188; signalling, 228; stoker, 399. Backfall, 298. Balance-wheel, 419. Ball cock, 366, _367_.