Mountains, Mountain Ranges, xiv, 224-6; atmospheric pressure on, i, 28, iv, 114-15, 170, ii, 245; block, iii, 138-9, xiv, 117, 226; boiling point of water on, viii, 303; Brocken specters, i, 184-5; cirques of corries on, xiv, 58; civilization of, xv, 129-31; cloud caps and banners, i, 104-5; coast lines and, xiv, 248, 249; distinguished from plateaus, 28; economic importance, 237-9, 245; ephemeral character, iii, 11, 12, 130, xiv, 235; faulted, iii, 138-9, xiv, 226; folded, iii, 131-8, xiv, 36, 93-4, 96, 226-34; forests on, xiv, 238-9; formed by erosion of plateaus, iii, 139-40, xiv, 225, 226; formation complex, iii, 140-1; granite cores of, 112, xiv, 110-11; heights determined by barometers, 124; hot springs of, 143; igneous intrusions, 228, 230, 232-3, 234; influence of, on human history, 10, 236-45, xv, 136, 137-8; lightning dangers, i, 156; making of in various eras, iii, 187-91, 205-6, 213-14, 218-19, 224-6; metamorphism in, xiv, 234; old and young, 235-6; ores and mines, 234, 237-8; peoples of, 245, xv, 129-31; plants and animals of, xiii, 321, 381, xiv, 365-6, 370, 376-7; rainfall and, i, 111, xiv, 354-5; rime on, i, 121-2; rock weathering on, iii, 23, 24, xiv, 40, 233-4; ruggedness due to erosion, 234; St. Elmo's Fire, i, 157; shadows in sky, 169-70; snow-line on, iv, 183-4; solar radiation on, i, 210; sound intensity on, 186; structural topography of, xiv, 94; stunted trees, xiii, 367; temperature on high, i, 19; volcanic, iii, 139, xiv, 225-6, 327 (see also Volcanic Cones); weighing of, ii, 68-9; wind types, i, 132-3 Mountain Sickness, i, 328, ii, 144, 150 Mountain Streams, harnessing of, v, 79-81; material transported by, xiv, 52, 233-4 Mountain Systems, xiv, 227 Mount Wilson Observatory, ii, 147-8; program and equipment, 152-61 Mouse-hunter (weasel), xii, 349 Mousterian Implements, xv, 100, 105, 107-8 Mouth, cavity as resonance chamber, iv, 232; dryness of, in fear, ix, 166; germs in, x, 201, 202, 219, 289; grasping organ, ix, 82; opening of, in concussions, xi, 101; "watering" of, cause, ix, 165 Movement, perceptions of, xi, 165, 166, 170-1, 184, 185 (see also Motion) Moving Bodies, deflection by earth's rotation, i, 124-5, xiv, 32, 348; old theory of, ii, 63 Moving Pictures, iv, 347-9; business men and, xi, 340; color reproduction in, iv, 369; facial expressions in, xv, 63; of eclipses, ii, 212 Moving Picture Machines, v, 329-31; mercury arc rectifiers in, vi, 333 Moving Star Clusters, ii, 341-4, 379 Mozambique Channel, xiv, 273 Mudfish, xii, 152 Mud Hens, xii, 262 Mud Puppy, xii, 171 Mufflers, automobile, v, 165 Mulberry Tree, fruit, xiii, 55, 226; paper from, v, 290 Mule Killers, xii, 167 Mullein, hairy covering, xiii, 105