Earth, agonic lines of, iv, 246; ancient ideas, xvi, 58; antiquity, iii, 21, 43, 201, 218, xiii, 306, 314, 322, xiv, 29, (see also Geological Ages); axis mutation, discovery, xvi, 124; center of universe, ii, 9 (see Geocentric Theory); centrifugal force of, iv, 75; changeableness of features, iii, 9-12, xiv, 3-4, 15-16, 28-30; changes in historic times, xv, 72; chemistry of, viii, 190-203; climate in past ages (see Climate); comets in relation to, ii, 279-80; crust (see Crust of Earth); density and specific gravity, iv, 98, 164, xiv, 11; diameter, ii, 64, 192, iii, 51; diameters, equatorial and polar, iv, 101, xiv, 9; electrification, i, 144, 145-6, iv, 269, 270, vii, 207, 209-10, 212-13; energy sources and losses, ix, 25-6; geological history, iii, 164-248, xv, 70-1, 72-6; gravity of, iv, 98-9, 101; heat from sun, amount of, 194; heat radiation and protection, 183-4; Hindu conception, ii, 36; interior, heat and condition, iii, 107-8, 120-1, 160, 162, iv, 164, xiv, 11-17, 312; internal heat utilized, v, 178-81, ix, 25, xiv, 15; internal waters, 151; land and water distribution, 20-7; life on, antiquity of, xv, 71; life on, beginnings, xiii, 298-304; life on, conditions necessary, ii, 242-5; life on, origin of, xii, 9-13; magnetic axis, iv, 250; magnetic field and lines of, 252-253; magnetic poles, 246, vi, 29-30; magnetism, ii, 178, 186, iv, 248-50, vi, 12, 29, 39-40; magnetism and internal iron, xiv, 11; magnetism in relation to aurora, i, 159-61; man's machining of, v, 251-67; mass of, iv, 98; motions (see Revolution, Rotation); origin, ancient ideas, ii, 366-7, xvi, 77, 78; origin, modern theories, ii, 373, iii, 158-63; rigidity, 107-8, xiv, 17; sciences of, xvi, 36; shadow in space, ii, 206; shape, 59, 69, 71, iv, 101, xiv, 9; shape, ancient ideas, ii, 10, 28, 30, 34-5; shrinking of, iii, 83-4, 108, 160, 162; size, ii, 162, 163; surface features, xiv, 9-11; temperature layers, 13-15; temperature ranges and control, ii, 243-4; temperature regulation by atmosphere, iv, 183-4; water circulation and supply, xiv, 134-5, 151; waters, past and future, ii, 244; waters within, iii, 109-10, 113-29; weight, ii, 68-9, 76, iv, 98, 164; wind and pressure belts, i, 128-9 Earth-Air-currents, i, 145, 371 Earth Movements, xiv, 32, 33-9; importance to human life, 341 Earthquakes, iii, 92-8, xiv, 330-43; faulting in, 39, 115, 128; lakes formed by, 203; submarine effects, 284; water table affected by, 136 Earthquake Waves, transmission of, xiv, 17, 332-3 Earthworms, xii, 51-3; power of distinguishing light, ix, 105 Earwigs, xii, 107