INDEX 



359 



Thermal maps, 240 

 Thermometer, 226 

 Thunder-squall, 302 

 Thunder-storms, 301 



shape of, 303 

 Tibet, 11 



Tides, 333, 334, 338 

 Topographic features of shores, 152 

 Topographic map, 6 

 Topography of ocean bottom, 325 

 Tornadoes, 285, 304 

 Torrid zone, 310 

 Trade-winds, 274 

 Transportation of sediment, 59 

 Tributaries, growth of, 71 

 Tropic of Cancer, 216 

 Tropic of Capricorn, 216 

 Tropical cyclones, 295 

 Tropical zones, 311 



climate of, 315 

 Tuscarora Deep, 325 

 Typhoons, 296 



Undertow, 152, 153, 334 

 Uniform climate, 309 

 Unstratified rocks, 17 



Valley breezes, 250 

 Valley flats, 62 

 Valley glaciers, 105 

 Valley systems, 72 

 Valley trains, 126 

 Valleys, 52 



courses of, 68 



deepening of, 59 



drowning of, 80 



lengthening of, 65 



mature, 72 



old, 72 



submerged, 184 



widening of, 61 



young, 72 

 Veins, 41 



Vernal equinox, 213 

 Vesuvius, 162 

 Volcanic ashes, 170 



cinders, 170 



cones, 175, 176, 325 



Volcanic continued 



dust, 19 



eruption of Krakatoa, 19 



necks, 177 

 Volcanoes, 16, 160 



distribution of, 171 



Hawaiian, 167 



number of, 171 



topographic effects of, 173 

 Vulcanism, causes of, 180 



Warm currents of ocean, 330 



Water gaps, 78 



Water hemisphere, 4 



Water surface, 31 



Water table, 31 



Water vapor, 29, 221, 251 



amount of, 255 



circulation of, 252 



condensation of, 257 



in the air, 224 

 Waterfall, 76 

 Waterspouts, 306 

 Wave-cut terrace, 154 

 Waves, 152, 334 



deposition by, 155 



erosion by, 153 

 Weather Bureau, 284 

 Weather maps, 283 

 Weather predictions, 296, 299 

 Weathering, 25, 28, 44 

 Wedge work of ice, 26 

 Wells, artesian, 32, 36 

 Westerly winds, 274 

 Whirlwinds, 303 

 Wind, abrasion by, 24 



velocity of, 277 



work of, 18 

 Wind-gap, 83 

 Winds, 267, 285 



causes of, 272 

 Winter, 233, 234 



Yellowstone Lake, 145 

 Young valley, 72 

 Youth of valleys, 72 

 Youthful topography, 72 



