196 B, Siliman— Geological and Mineralogical Notes 
Nevada, full of evidence of hot springs, solfatara and volcanic 
action, and yielding such mines as those of the Comstock lode and 
of Aurora, Bodie, and the White Mountains; or again, those like 
the Toyabe range, yielding silver with base metals, as antimony, 
lead, arsenic, copper, zinc, &c., as is also true in a more marked 
degree of the Humboldt range. So, in the present case, we find 
in the Wahsatch and Oquirrh ranges ores of silver, either argen- 
tiferous galenite, or largely epigene species secondary to galenite, 
with some ores of copper, antimony, zinc, &c., from which silver 
is rarely entirely absent. Prof. W. P. Blake, in his catalogue of 
Californian minerals sent to the Paris Exposition (1867), dis- 
tinctly points out this parallelism in the metallic contents of the 
ranges of the American Cordilleras, and the same feature 1s 
fully recognized by Mr. King in his chapter on Mining 
tricts introductory to “Mining Industry,” vol. iii of the Geo 
logical Exploration of the Fortieth Parallel, p. 5. : 
The structure of the Wahsatch and Oquirrh ranges is fortu- 
nately exposed to view by the cafions, which cut profoundly 
into them from the valleys. It is in these cafions that mos of 
the mining districts are located, and through them the summits of 
the ranges are conveniently reached. 
The Big Cottonwood ‘and Little Cottonwood cafions, for 
example, expose profound sections of the Wahsatch range, cut 
eastwardly across the structure of these mountains, forming 
a V-shaped chasm with very precipitous sides and obliquely 
transverse to the axis of the main range. Thus the poy. A 
direction of the Little Cottonwood cafion is about N. 62° B, 
cutting the main range at an angle of about thirty degrees. 
rock extends up the cafion for several miles, the lines of original 
metamorphic of conglomerates, an opinion first suggested to m¢ 
- Blak i 
ing the Mormon Temple at Salt Lake City. These qualTy- 
ing operations have been confined to splitting the great fallen 
