1258 



INDEX. 



f. 



Page. 



Faribault, E. R., on gold ores of Nova Scotia 1213 



Farrington, 0. C, cited on meteorites 945,946,947,964 



Fassaite, source and rnode of formation of 314,370,383 



Fault openings, size of . 138 



Fault planes, importance of, in ground- water circu- 

 lation 130 



Faults, importance of, in ground-water circula- 

 tion.. - 130-131 



pore space added to rocks by . 127 



Fayalite, alterations and alteration products of 308 



chemical and physical constants of -- 197,308 



occurrence of -- 308 



Federal Loan mine, sulphureted hydrogen at 1107 



Feldspar, alteration of, to quartz and mica, thin 



section showing _ -- 704 



fragment of, cut showing enlargement of 626 



in igneous rocks, percentage of 937 



Feldspar group of minerals, character, occurrence, 



formation, and alterations of 252-265, 



294, 353, 380, 381, 625-627 

 Feldspar-porphyry, weathered, original structure 



preserved in . 526 



Feldspathoid class of minerals, alterations and 



alteration products of . 352-353 



Ferrates, deposition of ... .-. - 541 



Ferric chloride, hydrolysis of, equation showing... 108 



Ferric oxide in earth's crust, percentage of. . . 934, 937, 938 



in sedimentary and igneous rocks, ratio of, to 



ferrous oxide __ 950-951 



red or yellow soils produced by 469 



sources and modes of formation of 172,467,540-541 



Ferric sulphate, formation of, chemical reaction in- 

 volved in - 826,828 



reversible reaction of, with ferric sulphate, in 



presence of silver 1100 



solution of silver by, equation showing 1099 



F err o dolomites, formation of 242-243, 625 



Ferromagnesian silicates, alterations of 353 



Ferromagnesian sands, deposits of, character and 



origin of .___ 877-879 



Ferrous carbonate, formation of, chemical reaction 



involved in _ 828 



origin of, from basic ferric sulphate, chemical 



reaction in volved in . 828 



Ferrous chloride, precipitation of gold by, equation 



showing 1092 



Ferrous compounds, oxidation of 172 



precipitation of copper by _ 1101 



work of, in metamorphisrn 165 



Ferrous oxide, decomposition of, in rock weathering 536 



in earth's crust, percentage of 934,937,938 



in sedimentary and igneous rocks, ratio of, to 



ferric oxide 950-951 



occurrence of 467 



oxidation of 467 



precipitation of - — 540 



Ferrous silicate, formation of, chemical reaction in- 

 volved in. _ 828 



Ferrous sulphate, precipitation of gold by, equation 



showing 1093 



precipitation of silver by, equation showing. 1082,1100 



reversible reaction of, with cupric sulphate 1102 



reversible reaction of, with ferric sulphate, in 



presence of silver 1100 



Ferruginous cherts, origin of 829,830-831 



Ferruginous shales, origin of- 829-830 



Page. 

 Fine-grained rocks, rate of weathering of, as com- 

 pared with that of coarse-grained 



rocks 533-534 



Fischer, Alfred, on bacterial action in decomposi- 

 tion of carbohydrates 463 



on bacterial action in plant growth 452, 453 



on carbon dioxide in rain water, amount of 474 



on iron bacteria _. 826 



on nitrogen compounds, decomposition of 465 



Fissility, display of, by weathering ._ _ 525 



See also Fracture. 

 Fissility openings, importance of, in ground-water 



circulation __ 131 



size of 138 



Fissures, width of, effect of dip on 1201 



Flexibility of rocks, conditions affecting 188-189 



Flexures, occurrence of rich ore shoots near ... 1225-1226 



Flow of ground water, rate of 582-588 



See also Ground water; Water. 

 Flow of rocks, effect of, on texturesand structures. 760-762 



Flowage, zone of , circulation of water in 1029 



zone of, deformation in ._ _ 1011-1012 



relation of zones of anamorphism and kata- 



morphism to 187,190 



upper limit of 187-191 



Fluid inclusions in rocks, figure showing . _ 746 



sizes of cavities containing _ 658 



Fluoridation, definition of 206 



Fluorides, character, occurrence, and alterations of. 216 



Fluorine, percentage of, in earth's crust 936, 1002 



Fluorite, alterations and alteration product of. 373, 383, 396 



chemical and physical constantsof 197,216 



occurrence and alterations of 216 



Foerste, A. F., Shaler, N. S., and "Woodworth, J. B., 



on occurrence of graphitic coals 212 



Forces of metamorphisrn, consideration of. 39-40, 44, 45-57 

 Forchhammer, Georg, on magnesium content of 

 corals and marine shells forming 



limestone deposits 798,804 



on potassium silicate, dissolution of, in water .. 112 

 Forsterite, chemical and physical constants of . . . 197, 308 



occurrence and alterations of 308,311 



Forsterite, calcite, and quartz, alterations and alter- 

 ation products of 383,407 



Friction, internal, of ground water, character and 



influence of 153-154 



Fracture, secondary, veins produced by 1228 



zone of , circulation of aqueous solutions in.. 1022-1028 

 features of, and chemical reactions in... 1005-1009 



openings in. _ 1006-1008 



relation of zones of anamorphism and kata- 



morphism to 187,190 



Fracture and flowage, zone of, aqueous circulation 



in 1028-1029 



zone of, phenomena in... 1009-1011 



Fractures of rocks, causes and character of 599-602 



direction of 601 



intersections of, ore shoots at or near 1226-1227 



pore space added to rocks by _ r 127 



spacing of 600 



Fragmental rocks, classification of 784-787,853-904 



deposits composing 853-904 



France, basalt from, losses in, by weathering 509,522 



Franklinite, formation of 1125 



production of, from Smithsonite, equation show- 

 ing 1126 



Freezing, likeness of, to precipitation _ 113 



