of the mountain you see the osidian lying in huge masses and in boulders.
Joining this, and at one point interrupting it, is a tract of volcanic
ashes stratified, and the strata thrown up vertically in some places, as
though after the volcano had flung out the ashes there had come a terrific
upheaval of the earth.

The two borax lakes lie also near the shore of Clear Lake; the largest
one, which is not now worked, has an area of about three hundred acres.
Little Borax Lake covers only about thirty acres, and this is now worked.
The efflorescing matter is composed of carbonate of soda, chloride of
sodium, and biborate of soda. The object of the works is, of course, to
separate the borax, and this is accomplished by crystallizing the borax,
which, being the least soluble of the salts, is the first to crystallize.

The bottom of the lake was dry when I was there; it was covered all over
with a white crust, which workmen scrape up and carry to the works, where
it is treated very successfully. My nose was offended by the fetid stench
which came from the earth when it was first put in the vats with hot
water; and I was told by the foreman of the works that this arose from
the immense number of flies and other insects which fly upon the lake
and perish in it. Chinese are employed as laborers here, and give great
satisfaction; and about eight days are required to complete the operation
of extracting the borax in crystals.

Earth containing biborate of lime is brought to this place all the way
from Wadsworth, in the State of Nevada--a very great distance, with
several transhipments--to be reduced at these works; and it seems that
this can be more cheaply done here than there, where they have neither
wood for the fires nor soda for the operation.