98 MmmG industry. 



The Vein. — The geological features of the vein and its inclosing rocks, 

 its general structure, and the character and method of distribution of its ore- 

 bodies, have been so fully discussed in the foregoing chapter that, in what 

 follows, these matters will receive only such attention as may be made neces- 

 sary by their intimate connection with the branch of the subject under 

 present consideration. 



The course of the Comstock lode is nearly north and south, maintaining 

 a general conformity in direction with the trend of the Washoe Mountains, 

 in which it is contained. Its croppings extend in a broad, irregular belt along 

 the eastern slope of the range, at an altitude of about 2,000 feet above the 

 level of the plain to which the hills descend, and about 1,300 or 1,400 feet 

 below the summit of Mount Davidson, the highest point in the range. 



The western, or foot-wall, dips to the eastward from near the surface to 

 the greatest depth attained, at an angle varying from 35° to 55°. The east- 

 ern, or hanging-wall, is ill-defined, especially in the upper portion of the lode, 

 but at the depth of several hundred feet the two walls, or what are usually 

 recognized as such, descend with considerable regularity, dipping easterly at 

 about 45°. 



The size of the vein is irregular, the walls being in close contact with 

 each other at some points, and at others diverging and expanding, so as to 

 include between them masses of vein-matter several hundred feet wide. With- 

 in these immense spaces, filled by material of varied character, are the bodies 



tlie preparation of tliese chapters, and are commended to tlie reader as valuable 

 sources of information : The Eeports on Mineral Eesources by the United States Com- 

 missioner, Mr. J. Eoss BROWjSfE, and liis successor, Mr. E. W. Eatmond ; the Eeports 

 of the State Mineralogist of Nevada, Mr. E. H. Stretch, and his successor, Mr. A. F. 

 White ; Eeports of the Surveyor General of Nevada, Mr. S. H. Marlette; and the 

 ofl&cial reports of miniag companies. 



The plates illustrating this volume have been prepared from notes and drawings 

 obtained in the field during the progress of the survey ; the final work of preparing 

 them for the engraver has been done, under the supervision of the writer, by Mr. 

 Ellsworth Daggett, of New Haven, and Mr. A. Pohlers, of Washington, to 

 whose skill as draughtsmen, combined with a practical knowledge of the subject, they 

 owe much of whatever merit they possess. 



All money values quoted in this and following chapters, referring to the State of 

 Nevada, are, unless otherwise stated, expressed in coin. 



