Ocean, Oceans, annual discharge of rivers into, xiv, 135; atmospheric conditions over, i, 13, 14, 143-4, vii, 212; basins and shoal water line, xiv, 24-6, 287-8; basins, topographical features, iii, 52, xiv, 27, 286-90; birds of, xii, 251-4, 258, 264; chemical elements in, xiii, 196-7; circulation of water in, xiv, 298-9, 303-5; color of, viii, 40; coloring, to what due, xii, 17, xvi, 147; density of water in, v, 195-6, xii, 21-2; deposits on floor, iii, 52-5, 168, xiv, 284-6; depths, iii, 51, xii, 21, xiii, 72, xiv, 23-4, 26-7, 288-9, 290 (see also Deep Sea); depths still a mystery, v, 202; divisions, xiv, 22; earthquakes in, 336-7; erosive work (see Ocean Waves); evaporation, vii, 212; exploration of, xiv, 283-4; extent of distribution, 20-3, iii, 51; faulting in bed of, xiv, 39; floors, general flatness, iii, 52, xiv, 24, 284; floor level changes, iii, 83, 168, 206, xiv, 34, 253; floors never land, iii, 55, xiv, 290; floor, ooze of, xii, 17-18; former extensions, iii, 12, 54, 55, 130, 132, 165-224 (maps), 235, xiii, 298-9, xiv, 19; heating and cooling of, 346; historical importance, 305-11; metals found in, viii, 148; meteorology of, i, 271-83; organic life of, xii, 16-24, xvi, 146-8; organic life in relation to salts, ix, 174, 175; phosphorescence of, xii, 18-20, 84; potassium compounds in, viii, 143, 279; power from, v, 174 (see Tides, Ocean Waves); pressure of water in, v, 95, 201; salinity, iii, 51-2, viii, 138-9, 195, 196, 279, xiv, 295-6; salt of early, ix, 175-6; soundings, xiv, 284; surface form and tides, 291-5; temperature layers, xii, 21-2, xiv, 297-9; theories of origin, iii, 160, 163; thunder audibility, i, 193; volcanoes in, xiv, 285-6; wind and pressure belts, i, 128-9; wind charts, 271-6 Ocean Commerce, development of, xiv, 305-11 Ocean Currents, xiv, 303-5; altering courses, i, 345; charts, 271-6; deflection by earth's rotation, xiv, 32; plant and animal distribution by, 277, 278; seed-dispersal by, xiii, 346-8 Oceanic Islands, xiv, 276-9; plants of, xiii, 348 Ocean Steamers, development, v, 192-4; strains on, 194; turbines in, 153-4 Ocean Waves, base level of erosion, xiv, 254; cause, 299; coast destruction by, iii, 55-7, xiv, 44, 45, 46, 299-303; length, vi, 269; motion, v, 124; power uses, 174; quelled by compressed air, 124-5 Ocelots, xii, 364 Octopus, xii, 77 Odorous Oils, in mint plants, xiii, 205 Odors, ix, 97; adaptation to, 97, xi, 80-1; agreeable, enjoyment of, ix, 98; classification, xi, 79; digestion and, x, 320; inhibition effects, xi, 81; perception of, ix, 96, 97; spread of, iv, 131 Odyssey, historic value of, xv, 323-4