Pluvial climate, causes of, 143; during glacial periods, 141. Po, frozen, 98. Polaris, 272. Polar wandering, hypothesis of, 48 f. Pole and earthquakes, 305. Post-glacial crustal movements and climatic changes, 215-222. Poynting, J. H., cited, 8. Precessional hypothesis, 34 f. Precipitation, and glaciation, 114, 133; during glacial period, 118; snow line and, 139; temperature and, 94. Procyon, companion of, 280; luminosity, 278; speed of, 281. Progressive change, 241. Progressive desiccation, hypothesis of, 65 ff. Proterozoic, 4 f.; fossils, 6 f.; glaciation, 18, 144, 226, 266; lava, 211; mountains in, 209; oceanic salinity, 42 f.; oxygen in air, 234; red beds, 151; temperature, 146 f. Pulsations, hypothesis of, 65, 72 ff. Pulsatory climatic changes, 72 ff. Pulsatory hypothesis, 272. Pumpelly, R., cited, 271. Radiation, variation of, 275. Radioactivity, heat of sun and, 14 f. Rainfall, changes in, 93 f.; glaciation and, 50; sunspots and, 53, *58, 59; tree growth and, 79. Red beds, 151, 170. Rhine, flood, 99; frozen, 98. Rho Ophiuchi, variables, 248. "Rice grains," 61. Richardson, O. W., cited, 256. Rigidity, of earth, 307. Roads, climate and, 66. Rogers, Thorwald, cited, 101. Romans, aqueduct of, 71. Rome, history of, 87. Rotation, of earth, 18 f. Ruden, storm-flood, 99. Rugen, storm-flood, 99. Ruins, as climatic evidence, 66; rainfall and, 60. Sacramento, correlation coefficients, 82 f., 85; rainfall, 86; rainfall record, 79. Sagas, cited, 105 f. St. John, C. E., cited, 236. Salinity, deep-sea circulation and, 176; effect on climate, 224; in North Atlantic, 228; ocean temperature and, 226; of ocean, 19, 120. Salisbury, R. D., cited, 111, 125, 129, 139, 156, 206, 269, 271. Salt, in ocean, 223. San Bernardino, correlation of rainfall, 85. Saturn, and sunspots, 243; sunspot cycle and, 62. Sayles, R. W., cited, 183. Scandinavia, climatic stress, 100 f.; fossils, 271; post-glacial climate, 271; rainfall, 107; storminess, 57, 107; temperature, 216. Scandinavian center of glaciation, 113. Schlesinger, F., cited, 275, 278, 298, 301, 305. Schuchert, C., cited, 3, 5, 23, *25, *123, 138, *145, 168, 169, 172, 188, 193, 196, 198, 200, *201, 206, 211, 230, 265. Schuster, A., cited, 61, 244, 294, 296. Sculpture, Maya, 96. Sea level and glaciation, 119. Seasonal alternations, 28 f. Seasonal banding, 183 f. Seasonal changes, geological, 183. Seasons, and earthquakes, 294, 295, 297, 299; evidences of, 169. Secular progression, 17 ff., 188. Seistan, swamps, 171. Sequoias, measurements of, 74 ff.; rainfall record, 79. Setchell, W. A., cited, 1. Shackleton, E., cited, 125. Shapley, H., cited, 246, 247, 254, 256, 275. Shimek, E., cited, 157, 161.