Klamath Mountains, California. — Hcrshcy. 143 
bluish color derived from the large constituent of ground ser- 
pentine, but oxidation has penetrated to a depth of fifteen to 
twenty feet, the color near the surface being a light reddish 
brown and below this a yellowish brown without the red tint. 
Such a deep oxidation and reddened surface I have not ob- 
served in the similar deposits of the Swift creek or other glaci- 
ated valleys of these mountains. It is one of the chief factors in 
giving this deposit the appearance of considerably greater age 
than any glacial deposit which I have heretofore described 
from this county. 
About 1000 feet below the Xash mine buildings, the old 
valley of Cofifee creek, several hundred feet wide, is obstructed 
by a slight moraine of serpentine debris, with some gabbro 
and a few granite boulders of fine grain occurring in place 
at the head of the main I'nion creek valley. The moraine is 
probably 100 feet high and 300 feet wide. Its topography 
is not distinctly morainic and I had long considered it a land- 
slide, but a more thorough examination of its interior afford- 
ed by a deep cutting, revealed its glacial character. 
Above the obstruction the valley has the form of a basin 
about 1200 feet long and 300 to 600 feet wide, entered on the 
south by the narrow valley of Union creek. This basin was 
the floor of the glacier. On issuing from the narrow Union 
creek valley, the glacier spread out like a fan, turning up the 
main Coffee creek valley a short distance and forming the 
short moraine at the mine ; and flowing down the valley a lit- 
tle farther to form the short moraine at the obstruction men- 
tioned above. The Coffee creek valley both above and below 
those points presents no evidence of glacial actjon except near 
the head. 
Immediately I'lpon the retreat of the glacier from its max- 
imum extension, the deeper portion of the basin was occupied 
by a glacial lakelet, such as are commonl\' foiuid in all recently 
glaciated regions. This lakelet ])robablv occu])i-ed between five 
and ten acre^. A considerable remnant of its deposits has been 
uncovered and beautifully exposed by the mining operitions. 
It is a bed of dark brown, finely laminated, non-pebblv hori- 
zontal silt, ten feet in thickness. It aboimds in vegetable debris 
such as fir leaves and small i)ieces of driftwood, l^rccisely 
.similar deposits are now farming in the glacial lakelets of the 
higher vallevs. 
