LIST OF ILLUSTRATIONS. 



FIGS. 



PAGE 



44a. View of the Bertha zinc mines, Wythe Co., Va. From a photo- 

 graph by A. E. W. Miller 173 



45. Section at Franklin Furnace, N. J., showing the geological rela- 



tions of the f ranklinite ore body. After F. L. Nason 176 



46. Section of the White Cap chute, Leadville, showing the geological 



relations of the ore, and its passage into unchanged sulphides 



in depth. After A. A. Blow 184 



47. Geological section of the Eagle River mines, Colo. After E. E. 



Olcott 187 



48. Geological section at Aspen, Colo. After A. Lakes 188 



49. View of the Bunker Hill and Sullivan mines, Wardner, Idaho. 



From a photograph loaned by E. E. Olcott , 193 



50. Section at Eureka, Nev. After a plate by J. S. Curtis 197 



51. Geological cross sections of strata and veins at Newman Hill, near 



Rico, Colo. After J. B. Farish 208 



52. Geological cross sections of strata and veins at Newman Hill. 



After J. B. Farish 209 



53. View of Lower Creede, Colo. From the Engineering and Mining 



Journal 210 



54. Geological section of the Black Hills. After Henry Newton 217 



55. Cross section of vein at the Alice mine, Butte, Mont. After W. P. 



Blake 220 



56. Two sections of the argentiferous sandstone at Silver Reef, Utah. 



After C. M. Rolker 226 



57. Section of Comstock Lode. After G. F. Becker 233 



58. Geological section of the Calico district, California. After W. 



Lindgren 242 



59. View of the Union diggings, Columbia Hill, Nevada Co., Cali- 



fornia. From a photograph 243 



60. View of the Timbuctoo diggings, Yuba Co., California. From a 



photograph 244 



61. Generalized section of a deep gravel bed, with technical terms. 



After R. E. Browne 246 



62. Section of Forest Hill Divide, Placer Co., California, to illustrate 



the relations of old and modern lines of drainage. After R. E. 

 Browne 247 



63. Sections of the Crimora manganese mine, Virginia. After C. E. 



Hall 263 



64. Geological sections illustrating the formation of the manganese 



ores in Arkansas. After R. A. F. Penrose.. 264 



65. The Turner mine, Batesville region, Arkansas. After R. A. F. 

 Penrose 265 



66. Section of the Great Western cinnabar mine. After G. F. Becker. 268 



67. Horizontal section of the Etta granite knob, Black Hills. After 



W.P.Blake.. . 273 



, 



