Mixtures, compared with compounds, viii, 15; explosions of, 62; heat and cold production by, iv, 174-5; separation by vapor pressure, viii, 305 Mizar, double star, ii, 123, 334 Mocking Bird, xii, 269 Modesty, clothing and, xv, 253; custom and, 254-5 Mohammed Ibn Musa, xvi, 103 Mohammedan Astronomy, ii, 37-9 Mohammedanism, development of, xv, 199; polygamy allowed by, 289 Mohawk Valley, importance of pass, xiv, 194; origin, iii, 232; rock faulting, 91 Moissan, electrical work, xvi, 176; Arc Furnace, vii, 303 Moisture (atmospheric) climate determined by, xiv, 351-6; temperature effects, 352-4; vegetation determined by, 364, 366, 372, 377-8, 380, 381; atmospheric (see Humidity) Molar Solutions, viii, 118-19, 379 Molasses, production and use, viii, 242, 243, xiii, 215; vitamines in, x, 262 Mold, cause of formation, i, 61; disease-producing, x, 196; reproduction, xiii, 164 (see also Fungi) Molecular Theory, viii, 23-5; history of development, xvi, 91, 133-4 Molecular Weight, viii, 92; boiling point and, 299-300; diffusibility and, 108; differences, to what due, iv, 110; found by vapor pressure, viii, 305; in relation to actual weight, 109; of proteins, 351 Molecules, iv, 21, vi, 109, viii, 379; arrangement in relation to crystals, 203, xvi, 164; attraction of, viii, 306; possible variations in, iv, 143; condition at absolute zero, iv, 142-3; discrimination from atoms by Dumas, xvi, 162; dissipation of energy, 134; electrical balance and unbalance, i, 142, 143; electrical charges of, viii, 121; escape from liquids, iv, 167; ether in, iv, 181; formulæ of, viii, 91; fundamental vibrations of, iv, 363; in solids, liquids and gases, iii, 309, iv, 22, 131-3, 152-3, 363, viii, 23-4, 106; in solutions, 311-12; invariability law, 110; laws of, 106-10; magnetization of, iv, 245, 253; momentum, viii, 109-10; monatomic, 309; motions of, iv, 132-3, 363, viii, 23-5, 305-6; motion increased by heat, iv, 138-9, 144, 152-3, viii, 25, 37-8, 107, 108, 309, 310; number, vi, 112; number of, in gases, iv, 133, viii, 25, 108-9; polymerization, 219; size, vi, 112, viii, 24, 306; structure, 25-7, 306; structure, chain and ring, 233; structure, ether, 217, 224; structure in hydrocarbons, 51; structure in proteins, 351; structure and color, 258, 259, 312; structure and physical state, 207, 298; structure in relation to boiling and freezing points, 298-9; structure revealed by polariscope, 309; velocity of, iv, 133, viii, 24 Moles, xii, 366, 367-8 Molluscoids, iii, 259, 263, 270; origin of name, xii, 47 Mollusks, iii, 260, 272-6, xii, 57-80; deep sea, 23; in sea plankton, 19; sponges and, 32