be adapted to the size of the
particles of gold, and the nature of the material in which they are
found. In placer mining, the earthy matter containing the gold, called
the "pay-dirt," is washed in water, which dissolves the clay and
carries it off in solution, and the current sweeps away the sand,
gravel and stones, while the gold, by reason of the higher specific
gravity, remains in the channel or is caught with quicksilver. In
quartz mining the auriferous rock is ground to a very fine powder, the
gold in which is caught in quicksilver, or on the rough surface of a
blanket, over which the fine material is borne by a stream of water.
About two-thirds of our gold is obtained from the placers, and
one-third from the quartz.

A mine is defined and generally understood to mean "a subterraneous
work or excavation for obtaining metals, metallic ores or mineral
substances;" but this definition does not apply to our placer mines,
which are places where gold is taken from diluvial or alluvial
deposits. Most of the work is not subterraneous; it is done in the full
light of day. In some of the claims the pay-dirt lies within two feet
of the surface; in others it lies much deeper, but all the
superincumbent matter is swept away.

Water is the great agent of the placer miner; it is the element of his
power; its amount is the measure of his work, and its cost is the
measure of his profit. With an abundance of water he can wash every
thing; without water he can do little or nothing. Placer mining is
almost entirely mechanical, and of such a kind that no accuracy of
workmanship or scientific or literary education is necessary to mastery
in it. Amalgamation is a chemical process it is true, but it is so
simple that after a few days' experience, the rudest laborer will
manage it as well as the most thorough chemist.

It is impossible to ascertain the amount of gold which has been taken
from the mines of California. Records have been kept of the sums
manifested at the San Francisco Custom House, for exportation, and
deposited for coinage in the mints of the United States; and there is
also some knowledge of the amounts sent in bars and dust to England;
but we have no account of the sums carried by passengers to foreign
countries and coined elsewhere than at London, or used as jewelry, or
of the amount now in circulation in this state. According to the books
of the Custom House of San Francisco, the sums manifested for export
were as