1282 



INDEX. 



Page. 

 Sulphides, character, occurrence, formation, and 



alterations of 212-216, 472, 622, 



627, 957, 9:8-959, 1075, 1104-1105, 1108-1118 



formation of, from sulphates ■ 472 



oxidation of, oxygen consumed in 951-952, 955 



precipitation of gold by - 1095-1036 



solution of - 1106-1108 



Sulphides of iron, oxidation of iron of 468 



volume changes incident to production of 468-469 



Sulphides of metals, process of extracting 1174 



Sulphur, in earth's crust.. 936,938,957 



in ocean and sea salt _ 943-944 



in rocks and meteorites. 957-959 



oxidation of. ---. 468,951-952,955 



Sulphur Bank, California, mineral vein formation 



at - 1059,1060,1064,1066 



sulphides in solution at 1106 



Stdphur-bearing minerals, deposition of 628 



Sulphur compounds, oxidation of 606 



Sulphur trioxide, percentage of, in earth's crust. . . 938 

 Sulphuret mines, diminution of richness in, with 



increase of depth 1188 



Sulphuric acid in salts of sea water _. 942 



formation of 468 



Sulphuric oxide. See Sulphur trioxide. 



Sulphurous acid in ground water ._ 93 



formation of 468 



Sunlight and sun heat, metamorphic effect of 51-53 



Surface induration of rocks, discussion of 546-549 



Surface tension of water, strength of ._ 150 



Suspension, materials transported in 556-557 



Suspension and solution, materials transported in. . 558 

 Symmetry of crystalline forms, change of, in min- 

 erals, and molecular change, altera- 

 tions produced by 399 



mineral stability determined by 360-362 



Syenite, losses in, by weathering, analysis showing. 508, 



515.522 

 T. 



Taconic controversy, causes of ._ 920 



Talc, chemical and physical constants of 200, 348 



occurrence of 350-351 



sources and modes of formation of. . . 228, 268, 270, 273, 

 274, 278, 282, 285, 286, 29U, 302, 303, 309, 312, 314, 

 318, 319, 327, 328, 337, 343, 351, 353, 354, 372, 375, 

 376,377,379,381,382,383,385,387,390,391,392, 

 393, 394, 397, 398, 399, 402, 403, 404, 405, 406, 625 

 See also Steatite. 

 Talmage, J. E., on a remarkable occurrence of sele- 



nite 788 



Teller, F., and von John, C, on zonal arrangement 

 of nietamorphic minerals peripheral 



to intrusive masses 719 



Telluride of gold, production of gold from, equation 



showing 1169-1170 



Telhirides, genesisof,speculationsconcerning.. 1120-1125 



occurrence and associations of 1119-1125 



precipitation of gold by 1096-1098 



Tellurium, association of, with gold 1170 



precipitation of gold by 1091 



Temperature, annual range of 437 



change in metamorphic effects of 53 



chemical changes and deformation as affected 



by 1013 



chemical work in belt of weathering as affected 



by 458-460 



decrease of, precipitation of metals by 1081-1082 



Temperature, gases, activity of, as affected by _ 61-62 



solubility of, as affected by increase of 72 



granulation and recystallization as affected by. 740 



ground-water action as affected by 157 



ground-water level as affected by 428 



increase of, with increase of depth from earth's 



surface 578-579 



ore deposition, as affected by 1015-1016, 1073-1074 



precipitation by 115-116, 1081-1082 



rock disintegration as affected by 434-439 



range of, at which work of water solutions is 



done 603 



relations of, to solubility 79-81 



zone of constant, in earth, depth of 590 



Temperature and solution, relations of 79-81 



Temperature of earth at surface and below, aver- 

 age _ 51-52 



Tenorite, alteration of, to malachite, equation show- 

 ing 1159 



formation of, equation showing 1158 



Tension. See Strain. 



Termites, effect of work of, on soils 448,449,456 



Textures of rocks, category of, produced by meta- 



morphism 37-38 



coarse, favorable to permanency 40 



rock flow as affected by 760-762 



weathering as affecting 524-527 



preservation of, after metasomatic alteration. 644-645 



Thawing and freezing, effect of, on rocks 440-444: 



Thermal factors involved in chemical changes, dis- 

 cussion of 182,208,362 



Thomson, Sir "William. See Kelvin. 



Thomson, "W., and Tait, P. G., on effects of u stress 



difference" 672 



Thomsonite, chemical and physical constants of _ 201,329 

 formation of, from anorthite, volume change 



incident to 633 



occurrence of _ 331-333 



sources and modes of formation of.. 261, 



292, 293, 295, 296, 372, 376, 388, 392, 402, 403 

 Thwing, C. B., and Austin, L. W., on volume of 



water at different temperatures 147 



Tidal forces, effect of, on movements of earth's 



crust 930 



Tilden, W. A., on carbon gases inclosed in rocks . 968, 969 

 Time as a factor in metamorphism, importance of. 41-42 



Tin deposits, character of.. 1038-1039 



Tin ores, formation of, modes of 1054-1055,1058 



Titanates, character, occurrence, formation, and 



alteration of 354-355 



Titanation, definition of 205 



Titanation and decarbonation, alterations pro- 

 duced by 400 



Titaniferous iron ores, deposits of 1044-1045 



Titanite, alterations and alteration products of 355, 



374,393,396,401 



chemical and physical constants of 201 , 354 



occurrence of 354 



sources and modes of formation of 227, 



228, 231, 354, 372, 385, 391, 407, 408 

 Titanium, in earth's crust and in original and sedi- 

 mentary rocks 933, 936, 974-975 



Titanium dioxide, percentage of, in earth's crust. 937, 938 

 Tolman, C. F., on balance between carbon dioxide 



in air and that in the ocean 968 



on pressure, effect of, on crystallization 103 



on Spring's experiments in compaction of clay. 100 



