Crowd-poisoning, i, 321 Crowds, psychology of, xi, 323-33; leaders of, 332-3; legal responsibility, 329-31 Crucibles, graphite, viii, 43; platinum, 173 Crucible Steel Process, vii, 312 Cruickshank, William, electrical work, xvi, 122 Cruickshank, Wm. Cumberland, medical work, xvi, 179 Crusaders, coffee not known to, xiii, 232; heroic crowds, xi, 326; paper introduced by, v, 290 Crusades, effect on medicine, x, 37; horse improvement by, xii, 307 Crust of Earth, xiv, 16; chemical constituents, iii, 308, viii, 19, 90, 118, 129, 138-9, 148, 190-1, 192; chemistry of, 190-203; layers in, 191-2; movements, iii, 76-98, xiv, 31-2, 33-9, 341 (see also Earth Movements); rocks in iii, 12-14, 110-12, xiv, 17-19; settling, cause of brontides, 196; specific gravity, xiv, 11; theory of formation, iii, 160; thickness, 17, viii, 191-2; waters in, iii, 113-29 Cryptograms, xiii, 63; cycads and, 309; earliest plants, 303; forests of, of Silurian, xv, 71; in coal age, xiii, 310; numbers, 168; reproductive process, 154-65; spore-dispersal by wind, 344; water necessary to fertilization, 300 (see Flowerless Plants) Crystalline Form, iii, 309-11, viii, 203, 312-13; solidification in relation to, iv, 163 Crystalline Rocks, iii, 378; of oldest eras, 169, 170-1, 189 Crystals, Crystallization, iii, 309-20, 377-8; cleavage, 310, 318, viii, 202; electrification by cleavage of, iv, 260; growth, iii, 311, 316; growth of alum, viii, 313; light polarization by, iii, 319-20, iv, 354; Mitscherlich's studies, xvi, 161; Pasteur's studies, 163-4; snow and ice, i, 115-16; water of, viii, 38; X-ray studies, iii, 311, viii, 313 Ctesibius, discovery of compressed air, v, 109-11; ignorant of atmospheric pressure, 112; inventions and theories, xvi, 91-2; water clocks, v, 59-62 Cuba, almiquis of, xii, 367; American occupation, x, 160; earthquakes in, xiv, 331; jute production, xiii, 241; sugar production, 215; tobacco production, 258; yellow fever eradication, x, 160-2, xiv, 356; zoölogy of, 274-5 Cuckoos, xii, 255-6 Cucumbers, as food, viii, 365; origin, xiii, 223 Cud Animals, xii, 311-12 Cugnot, Joseph, v, 207 Culinary Paradox, iv, 168-9 Cullen, Dr., refrigerating machine, v, 350, 354-6 Cullen, William, x, 88 Cultivated Plants, birthrate in, xiii, 51; original sources, 221-7, xiv, 381-2 (see also Garden Plants) Cultivation (soil), reason for, xiii, 92 Cultural Advance, requisites of, x, 107 Cumberland Plateau, xiv, 221; height, 27 Cumberland Valley, xiv, 167 Cumene, viii, 235, 253 Cumulo-Nimbus Clouds, i, 102, 103-4 Cumulus Clouds, 1, 98, 101-2, 103-4; air currents and, 293; formation of, 93 Cuneiform Writing, xv, 174, 175 (figs.), xvi, 60 Curassows, xii, 261