44 2 A Description of the Process of [August, 
similar explorations in the same class of depositions we 
have the experiences of our own times, and which explain 
bv comparison all the previous operations alluded to. 
in the year 1849, after the cession of the northern portion o 
Mexico to the United States of North America, the rich 
mineral district of California was at once invaded by hardy 
and intelligent bands of mining adventurers from all paits 
of the world, who, with little other means at their disposal 
but pick, shovel, and pan, soon fell upon the productive bais 
of rivers and rich ravines where the gold was trapped, 
derived from its original birthplaces, where it had been 
sparsely disseminated, to be dispersed by the subsequen 
disintegrations and denudations of the mountains them- 
selves, and deposited in a disengaged form for the first 
comer ; and so perfect were sometimes these concentrations, 
in certain localities where water once streamed, that, di- 
vested of its earthy matrix, the cleansed pure metal was 
found deposited, detained by its superior specific gravity, on 
the bare rock, and only hidden from vision by a slight 
covering of vegetable mould. In this manner, as an examp e 
of such concentration, a “ pot ” or “ find ” (in mining par- 
lance) to the value of £10,000 was collefted in a space ot 
1=; square yards, or within the limits of a particular mining 
claim,” at the foot of Mokulumne Hill, in a southern county 
of California, soon after the territorial transfer from Mexico. 
And in search of such locations we must account for the 
numberless shafts which still exist both in India and Peiu, 
and sometimes sunk within a few feet of each other, passing 
through the alluvium to a depth of 40 feet to the bed 
rock* 
These mining adventurers soon extended their explora- 
tions over the other recently acquired territories, and built 
Virginia city, the capital of Montana, with the gold derive 
from the alluvium of a river channel which they excavated ; 
and its inhabitants were the founders of an institution called 
the Vigilance Committee, with “Lynch law,” and by it ruled 
supremely for many years. But their surface diggings, by 
the manual operations alone of multitudes, were soon ex- 
hausted in every direction, and then their energies and 
powers of invention were dedicated to discover and explore 
deeper and more permanent depositions, along the western 
slopes of the Sierra Nevada, the Andes of the Western dei- 
ritories, and which originally were without doubt several 
miles higher than they are at the present time,— probably 
20,000 feet above the sea-level, — and of which, 01 whatever 
superior elevation they formerly had, the greater poition ot 
