Corona Discharge (electricity), vii, 10-11, 23 Corona of Sun, ii, 219-26, 184; appearance in eclipses, 213-14; comets and, 281; photographic studies, 128, 129; rotation, 121; study of, proposed method, 225-6; study in various eclipses, 211-12, 214, 218 Coronas, atmospheric, i, 183-4, 370 Coronium, discovery, ii, 211, 223 Corposants, i, 157-8 Corrasion, defined, iii, 29; by ice, 63-4; by sand, 72; in Grand Canyon, 40; potholes formed by, 39-40 Correlation, mathematical, i, 253 Correlation of Energy, iv, 40 Corries, of Scotland, xiv, 58 Corrigan, John, x, 112 Corrosion, chemical, viii, 10, 13, 100; Electrolytic (see Electrolytic Corrosion) Corrosive Sublimate, viii, 170 Cort, Henry, v, 316 Corti, Organ of, xi, 102 Corundum, iii, 327-8 Corvisart, x, 110 Corymb, flower-form, xiii, 50 Coryza, x, 295, 341 Cos, School of, x, 21-2; influence in middle ages, 37 Cosmogony, defined, ii, 362; theories, ancient and modern, 366-84, xvi, 58, 76-9, 80, 81-2, 84 Cossacks, bows and arrows of, xv, 214 Cotopaxi, Mount, xiv, 225 Cotton, as clothing material, ix, 311, x, 307, 308, 309; cultivation, xiii, 238; dyes for, viii, 259; fiber, 229, 254, ix, 30, xiii, 237; fiber to fabric, v, 269-83; humidity effects, i, 78; importance, xiii, 208, 235, 236; kinds, v, 269, xiii, 236; Mediterranean origin, xxiv, 382; mercerized, viii, 255; preparation for manufacture, xiii, 237-8; removal of, from wool, viii, 255; vegetable silk from, 255-6 Cotton Cloth, making of, v, 269-83 Cotton Crop, forecasts, i, 251 Cotton Gin, Macarthy's, xiii, 238; Whitney's v, 269-71, 376 Cotton Plant, xiii, 236-7 Cotton Seed, uses, xiii, 238 Cottonseed Oil, viii, 246; solidified, 232, 247 Cottrell, Dr., vii, 216 Cotyledons, xiii, 60; classification by, 176 Cougars, xii, 363 Coughing, reflex action, ix, 135, 258, xi, 20 Coulomb, electric quantity unit, iv, 280, 284, vi, 17, 69, 82, vii, 365, 374 Coulomb, C. A., electrical work, vi, 17-18, xvi, 122; quantity unit named for, iv, 280 Countertrade Winds, i, 130, 366 Counter Voltage, vii, 365; in motors, vi, 226-8, 232, 233, 236 Counting (see Numbers) Country Rock, definition and character, xiv, 105 Courage, motor origin, xi, 61 Courtship, among animals and birds, xv, 274-5 Cows, domesticating qualities, xv, 197; fat production by, ix, 298; milking by electricity, vii, 222, 226-7 Cow's Milk, for infants, ix, 33-4, 346 Cowries, xii, 73 Coyote, xii, 340 Crabs, iii, 260, 276, 279, xii, 85-7; deep sea, 23; hard and soft-shelled, 83; "no-body," 89; sponges and, 32 Cramps, from cold baths, ix, 313; significance, xi, 120 Cranberry, bogs, xiii, 382; origin, 225; ovary, 202 Cranes, (birds), xii, 262 Cranes, hydraulic, v, 101-2, 106