Babylonians, astronomy of, ii, 19-21, xvi, 56, 57-8, 61-2; cuneiform writing, xv, 174, 175 (fig.), xvi, 60; debt of Greeks and Egyptians to, 63, 66, 69, 70, 71; Hammurabic code, 63; history and civilization, 51-3, 55, 62-3; idea of cosmos, 77; magic of, 59; mathematics, 61, 62, 103; medicine of, x, 14, 15; science, remarks on, xiv, 96 Babyroussa, xii, 310 Bacilli, x, 195; of various diseases, 149, 165-6, 292, 295, 296, 298-9 Backstays of Sun, i, 169, 367 Bacon, calories in, ix, 299 Bacon, Francis, evolution known to, x, 136; Harvey's small esteem for, 66; influence on his times, 67; on brontides, i, 196; on knowledge, xi, 10; scientific work, xvi, 113, 115, 125, 131 Bacon, Roger, xvi, 100-1 Bacteria, anærobic, xiii, 312-13; atmospheric electricity and, i, 330; breeding of, true, x, 195; classification of, 195; destruction by disinfectants, viii, 332-3; destruction in blood, x, 209-11; disease-making (see Disease Germs); fermentation by, ix, 248; flowerless plants, xiii, 13; food of, ix, 27, 248; in air, i, 61; Chicago standards, viii, 332; in body, x, 201-2, 204; in intestines, ix, 247-9; in sea, xii, 16; Leeuwenhoek's studies, xvi, 107-8; low temperature effects, i, 32; luminous, 346, 349, xii, 20; nitrogen fixation by, i, 35, viii, 340, 345, 346, x, 193-4, xiii, 98, xiv, 66; number of species, xiii, 323; origin of, xii, 12; Pasteur's studies, xvi, 143; preserving foods against, viii, 372; sewage treatment by, 325, 327-9; single-celled, xiii, 166; size, i, 61, xiii, 63; soil, xii, 15; ultramicroscopic, x, 200; useful forms of, 193-4 Bacteriemia, x, 220 Bacteriology, x, 194; foundations of, 143, 196 Badgers, xii, 347-8 Bad Lands, iii, 139-40, 230, xiv, 62, 81-2 Bagehot, quoted, xvi, 198 Baglivi, x, 76, 77-8, 155 Bag-pipes, xv, 317 Baguio, Philippines, rainstorm at, 1, 110 Baguios, i, 136, 367 Bahamas, hurricane grass of, xiii, 344; sisal production, 240; wild fig tree, 18 Baikal, Lake, depth of, xiv, 204; in rift valley, 123 Bailey's Beads, ii, 87 Baking Powders, viii, 136-7, 223 Baking Soda, viii, 135-6, 146, 278 Balance, sense of (see Equilibrium Sense) Balanced Forces, v, 183-6 Balance Levers, v, 63-4 (fig.) 65 Balance Spring, invention, v, 65 Balance Wheels, v, 68-9, 71-2 Baldness, ancient treatment of, x, 12; hats and, 309 Balearic Basin, xiv, 291 Balfour, Francis, x, 131 Ball-bearings, iv, 93, v, 206 Ballistic Wind, i, 313-67 Ball Lightning, i, 149-52, vii, 205-6, 213-15; as ignis fatuus, i, 347 Ballon-sonde, i, 21, 367