Comparisons, measuring by, vii, 341 (see also Contrasts) Compass, (Gyroscopic), iv, 254-5, v, 201, 340, 384 Compass (Magnetic), vii, 365; compensation on iron ships, iv, 254, v, 340, vi, 42; development, xvi, 102; deviation, defined, iv, 247, vi, 42; disturbances accompanying aurora, i, 161; electric current effects, vi, 20, 88; invention, 29; magnet effects, 27, 32, 42-3; modern improvements, 41-2; needle, pointing and declination of, iv, 246-7, (see also Magnetic Needle); sun disturbances, vi, 40; variation, defined, iv, 247; variations on voyage of Columbus, 52-3, vi, 27 (see also Mariner's Compass) Compensators, electrical, vi, 253-5 "Complete Recall," xi, 378 Complexes, mental, x, 355-6; in hysteria, 361, 362 Composing Machines (see Linotype, Monotype) Composition of Forces, iv, 75-7 Compostella, Spain, shrine at, xii, 65 Compounds, Chemical, viii, 16, 100, 375; analysis of, 285-95; colors of, 312; combustion of, 61; constancy, 110, xvi, 160; contrasted with mixtures, viii, 15; decomposition, 101-2; electrical balance, 121; formation types, 20, 100; formulæ, 91; metallic, 130, 146; molecular weights, 92; multiple proportions law, 110; nomenclature, 97-8; organic (see Organic Compounds); substitution in, 102; unstable, 66; with water, 20, 38-9 Compound-Wound Dynamos, vi, 187, 188-9, 191-2 Compound-Wound Motors, vi, 233-5 Comprehensive Terms, xi, 191 Compressed Air, applications and uses, i, 25-6, 27-9, iv, 30-2, 106, 129-31, v, 111-38; discovery, 109-11; expansion effects, cooling by, iv, 191, v, 128-9, 351-3, xiv, 14; heat of, v, 126-8, 161, 351; methods of compression, 89-93, 126-7, 174; physiological effects, i, 329, iv, 31-2, v, 119-21; pressures used, i, 27 Compressed Air Locomotives, i, 26, 27, iv, 129, v, 133 Compression, heat of, i, 90, v, 126-8, 161, 351 Compressors, Air, v, 89-93, 127, 351 Compte, on sciences, x, 368 Comstock Mines, Nevada, iii, 366, 368; temperature in, 121 Concentration, chemical, viii, 310-11; mental, xi, 235-6, 378-9 Conchs, xii, 72-3, 73-4 Concordant Coasts, xiv, 248, 249 Concrete Buildings, value in earthquakes, xiv, 343 Concrete Dams, expansion joints, v, 71 Concrete Sciences, xvi, 42 Concrete Ships, v, 194-5 Concubinage, xv, 289, 290 Condensed Milk, scurvy from, x, 266 Condensers, electrical, iv, 265-7, vi, 170-4, 301-5, vii, 365; applications, vi, 285-6; capacity of, iv, 267-8; dielectric, vii, 366 (see Dielectric); discharge methods, iv, 267, vii, 366; in automobiles, vii, 138-9; oscillating currents, 373-4; plate, vi, 170, 293-4, 295; purpose, vii, 363; synchronous, vi, 262; use in wireless communication, iv, 314, vii, 263, 264, 266, 267 Condensers, Steam, v, 145, vi, 354-6