Klamath Mountains, California. — Hcrshey. 15 1 
hydraulic mine, owned by the Salmon River Consolidated 
Gold Mining Company, of which Mr. William Cooper is 
superintendent, and hence the property is popularly known as 
"Cooper's mine." There is a distinct old channel separated 
from the present river channel by a "rim" of high bed-rock 
and occupied by well water worn river gravel, abounding in 
huge boulders of Courtney granite. This old channel and its 
contents differ not in any important particular from the pres- 
ent river bed. The river deposit passes upward into a some- 
what different material in which local debris from the neigh- 
boring Crosby gulch plays an important part, and finally the 
latter excludes the granite boulders that are a distinguishing 
feature of the ordinary river deposits. 
This upper formation is composed of hornblende schist and 
debris form the various dikes occurring in the basin of Crosby 
creek. The material is coarse and largely angular. Blocks 
three feet in diameter occur. There was a little wearing b}^ 
stream action and no complete sorting of the material, yet the 
various pits of Cooper's mine show that it is everywhere dis- 
tinctl}^ and nearly horizontally stratified, probably by the ac- 
tion of the river. The thickness of the deposit is apparently 
from 150 to 250 feet. 
It is an alluvial fan formed at the mouth of the Crosby 
gulch where the stream issued into the broader valley of the 
main river. It is traceable for one-half mile or more up the 
gulch and it is here evident that when completed its central 
line was somewhat higher than the sides, forcing the creek to 
one side and compelling it to cut a rock gorge on the border 
of the deposit. This, together with the angularity of the ma- 
terial and the large blocks included, demonstrate that it was 
not formed under ordinary stream conditions, but by torrential 
action, the rock debris loosely scattered about in the basin 
having suddenly been swept down and out of the, gulch. This 
could not have come about through the sudden breaking of a 
lake barrier as Crosby gulch is extremely precipitous, rising 
on the southern face of a mountain reaching about 8000 feet 
above sea level, and within two miles descending to less than 
4000 feet of altitude. Because of directly facing the sun, this 
side of the mountain has nowhere been glaciated. The only 
source of such a large body of water as is required to explain 
