Sound-phenomena, nature of sound, 38, 229, 252, 332; inaudibility to some observers, 231, 274; its cause, 233; isacoustic lines, 234-236; variations in nature of sound throughout sound-area, 237; time-relation of sound and shock, 238, 253; origin of earthquake-sounds, 334; sound-phenomena of Neapolitan earthquake, 37; of Andalusian earthquake, 91; of Charleston earthquake, 133; of Riviera earthquake, 156; of Japanese after-shocks, 207; of Hereford earthquake, 229; of Inverness earthquake, 252; of Indian earthquake, 274 Structural changes, distribution of, in Indian earthquake, 315 Subsultory shock, 5 Sympathetic earthquakes of Japanese earthquake, 209; of Inverness earthquake, 259 Tanakadate, A., 177, 214 Taramelli, T., 76, 84, 85, 88, 90, 101, 138, 150, 165, 175, 325 Tectonic earthquakes, 5 Thrust-plane, Indian earthquake due to movement along, 318 Time-curve of Indian earthquake, 278; of principal epochs of earthquake-waves of distant origin, 338 Time-records, general inaccuracy of, 324 Time-relations of sound and shock in Hereford earthquake, 238; in Inverness earthquake, 253 Trigonometrical survey, revised, of Khasi hills after Indian earthquake, 312; interpretation of results, 314 Twin earthquakes, origin of, 32, 89, 120, 153, 174, 223; Neapolitan earthquake, 31; Andalusian earthquake, 87; Charleston earthquake, 108; Riviera earthquake, 149, 150; Hereford earthquake, 221 Undulatory shock, 5 Unfelt earth-waves, Andalusian earthquake, 82; Riviera earthquake, 157; Indian earthquake, 280 Uzielli, G., 143, 176 Velocity, maximum, of wave-motion, in Neapolitan earthquake, 35; in Indian earthquake, 272 Velocity of earth-waves, methods of determining, 39, 93, 127, 229; variation with depth, 336; form of wave-paths, 336; velocity of different phases, 339; of Neapolitan earthquake, 39; of Andalusian earthquake, 92; of Charleston earthquake, 126; of Japanese earthquakes, 188; of Hereford earthquake, 229; of Indian earthquake, 275, 279, 284 Visible earth-waves in Charleston earthquake, 110; in Japanese earthquake, 186; in Indian earthquake, 268 Volcanic earthquakes, 5, 70 Vorticose shock, 5 Water, effect of Andalusian earthquake on underground, 97 Waterfalls caused by fault-scarps of Indian earthquake, 305 Wave-path, 13 West, C.D., 272 Woolhope anticlinal and Hereford earthquake, connection between, 241 * * * * *