416 



GENERAL INDEX. 



Page. 

 Electrical action, local effect of, graphically represented. 367 



Electrical activity of ore bodies 309 



of ore bodies, causesof 310,311, 312, 313, 314 

 of ore bodies, method employed in de- 

 termining 402, 403 



of ore bodies, results 403 



of the Oonsolidated Virginia and Oali- 



fomia 319, 322 



of the Mexican 322 



of the Ophir 322 



of veins, earlier work on 313 



Electrical diflFerence between zinc strips of terminals 357 



Electricity of metallifereous veins, Foxonthe 309, 310, 311, 312 

 Hen wood on the . .309, 311 

 Reich on the ..309, 312, 313 

 von Strombeck on 



the 309,310 



Electrometer for measuring earth -potential 353, 367 



Electromotive force, how measured 295 



zinc, earth, copper 323 



Smpire- Imperial, analysis of water from the 152 



Energy, logarithmic distribution of, in faultina; 162 



transmission of, by fiiction 159 



Epidote. (5'ee illustrations.) 



circumstances favoring the formation of 211 



derived from chlorite 75, 213, 370, 384 



insolubility of 78 



mode of occuiTence of 212 



not formed at the expense of feldspar 76,216 



E(iuiputentials, contour and position of the, relative to the 



ore bodies 365 



surrounding the ore body 315 



Erosion in Washoe 285 



Errors in the electrical results for the 400 aud 500-foot 



levels, Richmond mine 343 



Eurt^ka District, electrical activity of 324 



Evaporation as a cause of precipitation 227 



E.vperiments on electrical activity of veins, hypothesis 



underlying 314 



Fault, as shown on the Sutro Tunnel level 282 



diminution of, near ends of Lode 185 



on the Lode, probably caused by rise of the west 



country 185 



on the Xltak section 281 



period of the 272 



to the north, in the Sierra N'evada 281 



Fault-curve, angle which tangentmakes with the horizon 172 



erjuations of 161, 163, 164, 165, 180 



pointofminimum radius of, curvature of ... 171 

 reduction and interpretation of the equation 



for. 



where two or more rocks are involved 172 



with double curvature 173 



Faulted surface, character of 177 



Faulting 285 



accompanied by parallel fissnring 174 



Church on : 156 



evidences of 157 



experiments on 165 



influence on the width of the Lode on the Belcher 



King on 156 



on the Vnion shrft section 279 



structural results of 156, 377 



theory ol', application to landslips .. 390 



Page. 



Faulting, theory of, application to the Corastock, and 



other instances 179 



theory of, application to veins 379 



von Richthofen on 156 



Feldspars, decomposition of 78, 215, 271, 385 



determined by Szab6's method 405 



external energj' involved in the decomposi- 

 tion of 234 



inferences concerning composition of 407 



of later homblende-andesite, analyses of . . . 155 



representative composition of 233 



Ferro-magnesian silicates, decomposition of 384 



Fissure, the Comstock, due to trachyte eruption, von 



Richthofen on 18 



Fissures in hanging wall produced by faulting 178 



in the Yellow Jacket dipinng west 277 



Floods supposed to have induced kaolinization 232 



Florida, raetamorphics near the 190 



FloweryPeak(F. 2), later homblende-andesite from near 133 



Flowery Range (F. 2), erosion on the 204 



Fluorine, instrumentality of, on the Comstock, von Richt- 

 hofen on 20, 380 



Foot walls, rise of, in faulting 378 



Forman shaft (D. 5), assay of augite-andesite from near 



the 155 



augite-andesite at the 30, 200, 202 



cross-section through the 278 



earlier homblende-andesite at the. . . 200 

 equation between temperature and 



depth in the 262 



eruptive diorite near the 192 



qnartz-poi-phyry of the 47, 196 



temperature observations in the 231, 



244, 252, 260 

 Fox, experiments on the electricity of metalliferous 



veins 309,310,311,312 



Freiberg, electrical activity at , 312, 313 



Friction, coefficient of, of Comstock rocks 186 



part it plays in faulting 158 



Reuleaux on 158 



Fuel, consumption of, by the mills 6 



transportation of 6 



Xiabbro-like diabase 115 



Gads,, steel and copper, electromotive force and polariza- 

 tion of 318,319 



Galleries, mine, length of 5 



Galvanomet€r 298, 320, 327 



Gate of Mnnroe, propylite from 144 



Geiger grade tollhouse (D. 1), 1,200 feet northwestof the. 



earlier homblende-andesite from 120, 121,406 



Golconda station, propylite from 141 



Gold and silver, proportions of, in Comstock bullion . .6, 9, IS 



Gold detected in "Washoe rocks 223 



Gold Hill and Virginia, population of 4 



Gold Hill mines, 2,500-foot level of the 284 



Gold Hill Peak (c. 4), propylite from 86.87,137 



Gould (£ Curry and Savage, bonanzas of 17 



Goupilli^re, Haton de la, on exploitation of mines 309 



Granite, assay of 154 



description of slides of 91 



feldspars of 406 



lithological description of 34, ;t73 



occurrence and age of .■ 190, 3«0 



Great Basin, character of 2 



Greenstone, meaning of the term 376 



