INDEX 



Numbers refer to pages. 



The principal references are indicated by black-face 

 type, e.g. 172. 



Absolute humidity, 45, 54 



pressure (steam), 154, 311 ff. 



temperature, 88, 311 



zero, 90, 311, 392 

 Acetic acid, 128 ff., 568, 582 

 Acetylene, oxy-acetylene flame, 82 



gas light, 171 

 Acid, acetic, 128 ff. 



citric, 129 



hydrochloric, 120 



lactic, 553, 568, 584 



sulfuric, 119 



Adaptation, a condition of natural 

 selection, 478, 480, 489 ff., 

 492, 512 



Aeration, agencies of soil, 470 

 Aerobic bacteria, 216, 574 

 Aeroplane, see Airplane 

 Ague, 527 

 Air, composition of, 76, 131, 546 



compressibility of, 231 



expansion of, 43, 64 ff., 97, 229, 231 



humidity of, see Atmosphere 



in soil, 469 



saturation of, 43 ff. 



weight of, 11 ff., 42, 64 

 Airplane, 389, 394 ff., 398 ff., 401 

 Alcohol, boiling point, 313 



distillation of, 562 



freezing point of, 90 



production of, 129, 562, 566, 568 ff. 



wood, 128 

 Algae, 220, 224 

 Alluvial soil, 456, 474 

 Alternating current, 320, 327, 328, 334 

 Altitude and air pressure, 10 ff., 391, 



392, 393 

 Aluminum, 167 ff. 



Ammonia, occurrence of, 155, 163, 

 546, 572 ff. 



use in refrigeration, 151 ff., 156 ff., 



164 



Ammonia water, 164 

 Ammonium sulfate, 163 ff. 

 Anaerobic bacteria, 216, 574 

 Anemometer, 23 

 Aneroid barometer, 89 

 Aniline, 164 



Animals and soil agration, 471 

 Anopheles mosquito, 525 ff., 542 

 Anther of flower, 484 ff., 494 

 Anthracene, 164 

 Anthracite, 144, 414 

 Anthrax, microorganism causing, 589 



cure and prevention of, 594, 598, 



605 



Anticyclone, 21, 31 ff. 

 Antiseptic, see Germicide 

 Antitoxins, artificial, 600, 602, 606, 608 



natural, 593 ff., 599, 600 ff. 



public control of, 605 

 Arc, electric, 174 ff., 248 

 Arch bridge, 287, 289 

 Archimedes, principle of buoyancy, 

 340 ff., 368 



and the lever, 258 

 Argon, 546 

 Arid soil, 457, 465 

 Armature, 322, 324 ff. 

 Arrowrock dam, 202 ff. 

 Artesian wells, 194 ff. 

 Artificial gas, 119, 145, 161 ff. 

 Artificial selection, 479 ff., 496 

 Aseptics, 122, 582, 586, 599 

 Ash, 125, 138, 144, 515 

 Ashokan reservoir, 191 



611 



