334 



INDEX. 



Double rings in Sequoia washingtoniana, 146 

 Douglass, A. E., 3, 6, 101 ff., 123, 124, 128, 135, 140, 157, 

 163, 238 

 Formula for tree growth, 160, 166 

 Douglass fir, curve of growth, 133 

 Drinking-water : 



Ancient supply of, 54, 57 !., 62 f., 72 f., 79 f. 

 At Gran Quivira, 86 

 Drought in Animas Valley, 71 f. 



Central New Mexico, 86 

 northwestern New Mexico, 81 

 Otero Basin, 73 

 years of, 54, 61 

 Dry farming, 50, 60 

 In ancient times, 69 



northern New Mexico, 81 

 Dunes of gypsum in Otero Basin, 40 ff. 



Movement of, 40 

 Dunwoody, H. H., cited, 192, 193 

 Durango, terraces in, 99 

 Dust in atmosphere, effect on temperature, 250 ff. 



solar atmosphere, as climatic factor, 274, 275 

 Dysentery in Tropics, 221 



Earth, cooling of, 289 



nature of interior of, 265 



periodical changes, of shape and size, 289 



shrinkage of, 289 

 Eberswalde, tree growth at, 120 f. 

 Egypt compared with Mayas, 184 



relation to Mayas, 185 

 Ekhohn, N. G., cited, 242 

 Elenmx ruins, 186 

 El Paso, famine at, 138 

 Emigration from Europe and rainfall, 89 

 Empire ranch, 25 



Rainfail of, 60 

 England, rainfail compared with California, 241 



relation of crops to rainfall, 241 

 Eocene, climate of, 283 



volcanism in, 287 



volcanoes in, in E«cky Mountains, 283 

 Eolian deposits of Otero Basin, 40 ff. 



erosion at Disemboque, 67 

 in Otero Basin, 73 

 relation to desert pavements, 24 

 Epochs of early American civilization, 88 

 Equatorial rains in Yucatan, 177 

 Erosion iu dry regions vs. wet, 16 f. 

 Escuintla, 218 

 Esmeralda, 186 

 Espita, rainfall of, 178 

 Europe, emigration from and rainfall, 89 

 "Exploration in Turkestan,'' 23, 26, 90 



"Fats," 243 



Fault-block mountains, 18 



Faunas: 



Jurassic, 281 



Lower Cretacic, 282 

 Festival of summer rains, 59 

 Fevers, effect on civilization, 220 f. 

 Fewkes, J. W., cited, 49, 91 

 Fire-places in ruins, 66, 73 

 Flagstaff, Ariz., tree measurements at, 102 ff. 



rainfall of, 13 

 Flare of trunk, effect upon tree measurements, 154 f. 

 Flood, tradition of, at Magdalena, 68 

 Floods in Mexico, 96 ff. 



periodic, in North America, 288 

 times of occurrence in Santa Cruz Valley, 54 

 Floras: 



Jurassic, 281 



Triassic, 280 



Upper Carbonic, 278 

 Fluvial deposits of Mexico City, 98 ff. 



Forbes, R. H., cited, 24, 44, 50, 51, £.3, 60, 106, 110 

 Forest, compared with jimgle, 178 



fires, effect upon tree growth, 134 

 Service of United States, 123, 131, 139 

 Forests and civilization, 186 



Humboldt's view of, in Mexico, 96 

 of Guatemala and Honduras, 211 



Yucatan, 176, 179 

 relation to — 



agriculture in Guatemala, 221 f. 



in tropics, 181 

 changes in climate, 190 

 density of population, 180 



of population in Guatemala, 217 

 ruins, 190 

 ruins in, 186 

 Formula for reducing tree growth to rainfall, 115, 166 



rainfall to tree growth, 113 f. 

 Fort Lowell, ruins near, 52 

 Forta. ancient, 61, 52, 56, 80 

 at Noiik, 63 



Satan's Canyon, 77 

 location in respect to rivers, 74 

 Whipple, Arizona, 105 

 (See also Walls for defense.) 

 Fowle, F. E. cited, 236, 246, 253 ff. 

 Free, E. E., cited, 37, 41 f., 138 

 Fresno, rainfall of, 157 f. 

 Frosts in Arizona, 9 

 Fruit and frosts in Arizona, 9-10 



Gaisa formation, 269, 270, 271, 292, 293 



Gallup, N. Mex., 76 



Gamio, M., cited, 97 



Gangamopteris flora. 279 



Gardner's Canyon, dry fanning in, 60 



terraces of, 25 

 Geikie, on Torridonian glaciation, 272 

 General Grant National Park, 142 

 Germany, tree growth in, 120 f. 

 Relation to sun-spota, 238 

 Gibbon's Ranch, ruins at, 59 

 Gila National Forest, 128 

 River, terraces of, 26, 28 

 Valley, climate of, 9 

 Gilbert, G. K., cited, 23, 37, 235 

 Glacial deposits, pre-Devonic, in Africa, 290 

 period, cause of, 5 



complexity of, 256 



probable reduction of temperature in, 242 

 relation to recent climatic changes, 206 

 email climatic cycles, 233 f . 

 terraces, 35 f. 

 periods in early geologic times, 256 

 Glaciation : 



Cambric, 269 



Devonic, 269 



Earliest Proterozoic, 272, 285, 286, 295, 296 



Latest Proterozoic, 270, 271, 285, 291, 292, 293 



Localization of, 234, 255 f. 



Permic, 267, 268, 279, 284, 285, 286, 2S7 



Pleistocene, 266, 284 



Pre-Devonic, 287 



Proterozoic — 



In Canada, 272, 273, 295, 296 

 China, 271, 272. 293, 294, 295 

 Norway, 270, 271, 292, 293 

 Relation to aridity, 258 



crustal movements and mountain-making, 

 256 ff. 

 Theories of, 206 f., 234 

 Torridonian, 272, 285 



Undated Proterozoic, 271, 272, 285, 293, 294, 295 

 Glossopteris flora, 268 

 Gran Qui vera: 



Abandonment of, 138 



