on goes, we have reason to believe that no gold
country ever possessed so large an extent of paying placer mines, with
the pay-dirt so near the surface, and with so many facilities for
working them as California. In Australia the diggings are very deep and
spotted, that is, the gold is unevenly distributed, and the supply of
water for mining is scanty. In Siberia the winter is terribly cold
during six months of the year. In Brazil the diggings were not so
extensive nor so rich as in this state. Here we have numerous large
streams coming down through the mining districts, very large bodies of
pay-dirt, and a mild climate.

After dividing placers into deep and shallow, the next classification
will be according to their topographical position, as into hill, flat,
bench, bar, river-bed, ancient river-bed, and gulch mines. Hill
diggings are those where the pay-dirt is in or under a hill. Flat
diggings are in a flat. Bench diggings are in a "bench" or narrow table
on the side of a hill above a river. Benches of this kind are not
uncommon in California, and they often indicate the place where the
stream ran in some very remote age. Bars are low collections of sand
and gravel at the side of a river and above its surface at low water.
River-bed claims are those beneath the surface of the river at low
water, and access is obtained to them only by removing the water from
the bed by flumes or ditches. Ancient river-bed claims are those of
which the gold was deposited by streams in places where no streams now
exist. Gulch claims are those in gullies which have no water, save
during a small part of the year. A "claim" is the mining land owned or
held by one man or a company.

The placer mines are again classified according to the manner in which,
or the instruments with which they are wrought. There are sluice
claims, hydraulic claims, tunnel claims, dry washing, dry digging, and
knife claims. In 1849 and 1850, the main classification of the placers
was into wet diggings and dry diggings, the former meaning mines in the
bars and beds of rivers, and dry diggings were those in gullies and
flats where water could be obtained only part of the year or not at
all. That classification was made while nearly all the mining was done
near the surface, before the great deposits of pay-dirt in the hills
had been discovered, and before ditches, sluices, and the hydraulic
process had been introduced. The class of mines then known as the "dry
digg