ee 
GENERAL DISTRIBUTION OF THE VOLCANIC FORMATIONS. 311 
remunerative ; but, even in such cases, it would be not safe to assume that 
the gold came from eruptive rock. At least, it would be difficult to prove 
that it did. Not afew of the miners, however, in the early days of gold- 
washing in California, were strongly inclined to believe that all the gold was 
thrown out from volcanic vents, and it was hoped that some lucky man would 
discover the central point from which the precious metal had been distributed. 
Mining has been carried on to a considerable extent, but without much 
pecuniary success, in the volcanic formations near Silver Mountain; but here, 
as in the Washoe Mines, there has been little or no native gold obtained. 
Ores of silver occur, which are auriferous, it is true, and a portion of the 
metalliferous contents of the Comstock lode consists of the native metals, 
silver and gold; but the former is present in much larger proportion than it 
is in the ordinary native gold of the Californian miner. 
But if the volcanic rocks themselves on the west slope of the Sierra are 
not metalliferous, except in a few localities, may not the same agencies which 
gave rise to eruptive phenomena on so grand a scale along the axis of the 
range have had something to do with the formation of the quartz veins in 
the bed-rock and their impregnation with gold? This question may be taken 
up again for some discussion in the section devoted to the distribution of the 
gold in the gravel; but it may be admitted that a positive answer is not 
easily given. 
In examining the geological features of the Sierra, we find quite different 
conditions prevailing in different portions of the range, with reference to the 
development of both volcanic formations and gravel. The southern portion, 
from Mariposa southward to the extremity of the chain, exhibits hardly any 
rocks which can properly be called slaty; there are, it is true, several areas 
of partly gneissoid and partly schistose rocks in the High Sierra, one of 
which passes through Red Slate Peak, while another traverses the summit 
of Mount Dana. It is not known that these bands, which are of somewhat 
doubtful character and origin, have ever yielded any perceptible quantity of 
gold. At all events, the Southern Sierra has never, when visited by any of 
our parties, exhibited any evidence of being sufficiently auriferous to make 
either surface or vein mining profitable. A large amount of work has been 
done and much money expended in the neighborhood of Kern River, whith- 
er, indeed, there was at one time a “rush” of excited miners; but it does 
not appear that anything in that region has been permanently profitable. 
Large deposits of gravel seem to be wanting; at least, none such have been 
