INDEX 



References are to pages. 



Abdo'men 234 



Adiaba'tic heating .... 123 



Agriculture, dry farming . . 101 



fertilizing 106 



irrigation 102 



of coastal plains 39 



See also Agricultural Soils. 

 Air, see Atmosphere. 



Alcohol, effects of 237 



Alimentary canal 233 



Al'kali soils 103 



effect of, upon plants .... 184 

 See Soils. 



Allu'vial cones (fans) ... 349 



Anemom'eter 144 



Angle of incidence and of re- 

 flection 63 



Animals 217 



circulation 227 



classification 217 



mver'tebrates 218-224 



insects 221 



protozo'a 218 



worms 220 



ver'tebrates 225 



distribution 254 



effects of glacial age upon . . 384 



food 233 



of mountain regions .... 432 



respiration 225 



Anther 201 



Antitox'in . . . . '. . r ;, . 216 



Aqueous humor 231 



Arctu'rus 5 



Arteries 228 



picture 229 



Arte'sian wells 318 



of coastal plains 398 



picture 315 



Ash, volcanic .... 442, 444, 453 



As'teroids, see Planetoids. 



Atmosphere, barometers . . 119 



barometric gradient .... 142 



capacity for moisture .... 124 



Atmosphere Continued 

 effect of water bodies on . . 137 



expansion 115 



forms of moisture, clouds, fog, 



etc 127 



heating 55, 123, 130-136 



height 122 



humidity, absolute and relative 126 



hygrom'eter 127 



I'sobars 136, 140, 141 



I'sotherms 135, 136, 137 



monsoons 153 



natural phenomena, rainbow, 

 mirage (meerahzh'), aurora . 128 



origin Ill 



pressure 117, 137 



rainfall 154-160 



spectrum 127 



weather maps ...... 136 



weight 115 



wind belts 148 



Atolls' 289, 307 



picture 286 



Attraction, see Gravitation. 



Auditory nerve 232 



Auricle 229 



Aurora bo-re-al'is 129 



Avalanches 431 



Axis of the earth 3 



Azores', volcanoes of .... 446 



Bacte'ria 209-218 



picture 213 



"Bad Lands" 328 



picture 327 



Barograph 122 



Barometers, mercurial and 



aneroid 119-122 



Barometric gradient ... 142 



Bays 399 



Beaches ........ 68-70 



formation 296 



See also Coastal Plains and 

 Coasts* 



