lt ~~ eT” oe ri 

INDEX 
ABYSSAL eruptive rocks, 184 
Accessory minerals of igneous rocks, 
37, 39 
Accumulation mountains, 394 
“ Acid igneous rocks, 40; mutual rela- 
tions of, 45 
Acid secretions in granite, 43 
Actinolite, 16; -rock, 78 ; -schist, 78, 
89 
Adularia, II 
fZolian basins, 421; rocks, 56; soils, 
391 
African lakes, 419 
After-action. See Pneumatolytic action 
Agate, 5 
Agglomerate, volcanic, 53, 197 
Alabaster, 30, 66 
Alaska, indented coast of, 423 
Albite, 12, 13 
Alderley Edge, ores at, 261 
Alkali-felspar rocks, 41 
Allotriomorphic (anhedral) minerals, 
36 
Alluvial basins, 420; clay, 61; soils, 
349 
Almandine, 24 
Alpine type of folds, 398 
Alps, 143, 397, 401 
Alteration of rocks, 37, 212 
Alteration-pseudomorphs, 38 
Alum shale, 63 ; slate, 76 
- Amazon, plains of the, 411 
Amber, I0o1 
Amethystine quartz, 6 
Amianthus, 17 
Amphibole group, 16 
431 
Amphibolites, 78 ; soils from, 382 
Amygdules, 125 
Analcite, 26 
Andalusite, 25, 216; -slate, 77 ; -horn- 
fels, 79 
Andes, 143 
Andesine, 12, 13 
Andesite, 48, 86, 87, 89; -tuff, 54. 
Anhedral (allotriomorphic) minerals, 36 
Anhydrite, 29 
Animal-tracks, 118 
Animals, geological action of, 371 
Anorthite, 12, 13 
Anorthoclase, II 
Anthracite, 71 ; -slate, 76 
Anticlinal double-fold, 139 
Anticlines, 136, 392 
Anticlinorium, 140 
Antrim, plateau-basalts of, 211 
Apatite, 30; veins of, 218, 265 
Aphanite, 86 
Aplite, 42 
Appalachian Mountains, 399 
Aqueous rocks, 55 
Aragonite, 29 
Aralo-Caspian depression, 412, 419 
Archean rocks, 227, 305 
Arctic plant- and animal-remains in 
Pleistocene, 98, 318 
Arenaceous rocks, soils from, 383 
Arenaceous shale, 82 
Argillaceous rocks, 76, 82, 93; con- 
cretionary, 124; soils from, 384 
Arkose, 61, 373 
Artesian Wells, 360 
Asbestos, 17 
