INDEX 



[References to illustrations are indicated by asterisks accompanying page 



numbers. When an asterisk precedes the citation of a group of pages it 



means that several illustrations are included] 



Agar, 89, 90* 



Air, *1-112; boiling point of, 119; 

 circulation of, *16-18 ; and com- 

 bustion, *63~72 ; composition of. 

 73-74 ; compressibility of, 57-58 ; 

 expansion of, 58-60 ; expansion of, 

 when heated, 15; gases of, 73; 

 how warmed, 32, 33 ; a mixture, 63, 

 73^ movements of, 144-145* ; prop- 

 erties of, *1-20 ; structure of, 57- 

 62 ; and water, 21-31 ; weight of, 

 *7-12 



Air pressure, *7-13, 42, 129, 131 ; 

 and altitude, 11, 12*, 13*; meas- 

 urement of, 5*, 8 ; shown on 

 weather maps, *39-41, 48*, 49* ; 

 and winds, 39 



Alcohol, 119, 140, 351-355; and 

 efficiency, 352-353 ; and evapora- 

 tion, 121 ; and the food supply, 

 354 ; and the nation, 353-354 



Alimentary canal, 338, 339 



Altitude and air pressure, 11, 12*, 

 13* 



Aluminium, 69, 140 



Ammeters, practical uses of, 206- 

 208 



Ammonia, 119, 161, 314 



Ammonium sulphate, 293 



Aneroid barometer, 8, 9*, 10 



Animals as soil-formers, 285-286, 

 290 



Anopheles, 110* 



Antares, 278 



Anticyclone, 44, 47 



Antimony, 69 



Anti-typhoid vaccination, 104 



Aphides, 313 



Arcturus, 276 



Argon, 73, 74 



Armature, 236 



Arsenic, 69 



Artificial selection, 389 ; progressive 

 results of, 390*-393 



Assimilation, 334, 344 ; and respira- 

 tion, 334-335 



Atmosphere and water on the moon 

 246, 249 



Atmospheric pressure, *5-14, *39- 

 51, 129, 131 



Atomic theory, 67, 68 



Atoms, 67 



Auricle, 341* 



Auriga, 275 



Automobile, 188* 



Automobile storage battery, 221*, 

 222-223 



Bacteria, *90-108, 160, 162 ; of the 

 air, 85-90 ; upon bread, 99 ; car- 

 ried by flies, 105*, 106*, 107*; 

 colonies of, 90* ; in cultivation, 

 96 ; and decay. 94 ; and disease, 

 95 ; distribution of, 97 ; in milk, 

 101* ; photomicrographs of, 93* ; 

 size and growth of, 92, 93 ; of the 

 soil, 313-314 ; sources in lakes 

 and rivers, 162; useful, 95; in 

 water, 160, 162 



Bacteriology, 93 



Balance of life, 380-382 



Balloons, 138-139 



Barium, 69 



Barograph, 11, 12* 



Barometer, *7-ll, 135; aneroid, 8, 

 9*, 10; graduation of, 10, 11*; 

 mercurial, 9, 10* 



Beehive, the, 273 



Benzene, 119 



Benzoate of soda, 359 



Bicycle, 3, 12 



Big Dipper, 269, 270, 271*, 272, 273 



397 



