depth of 100 to 125 feet and have a capacity of from 450,000 to 500,000 yards per month. All California dredges are electrically operated.

The most important points to be considered in the selection of a dredge suitable for a particular piece of gold dredging property are the funds available, transportation facilities, area of the dredging ground, its depth and nature. A successful gold dredging enterprise must consist of three essentials: (1) a suitable piece of dredging property proven to contain sufficient gold to warrant dredging; (2) sufficient money to properly equip the property; and (3) a good substantial gold dredge built to suit the particular ground. The point of transportation facilities

for the heavy dredge parts is not of great importance here in California. It is impracticable to build a dredge larger than three cubic feet to dredge ground only nine feet deep, and obviously, in hard cemented ground, or in ground containing big boulders, the dredge should be as large as possible. A chart giving dredge capacities and costs may be found on page 62.

Between the years 1901 and 1905, gold dredging in California was considered at its height. The large dredging

companies had prospecting engineers in search of gold dredging lands, and there is no doubt that the most desirable properties were secured. However, tracts of land that were then considered too low in value to work are now being successfully dredged. The gold production in this state in 1905 was some three millions of dollars and in 1921 just a little under eight million.

Gold dredging has proved a very promising phase of the mining industry to engage in, due principally to two factors, the price of the product-gold-never fluctuating and with no danger of overproduction, and few men being employed, eliminating the question of labor trouble. The big stumbling block is the lack of ground suitable for dredging. This factor has become increasingly important until at present the future of this phase of mining in California is definitely limited.

The stabilizing effect of gold dredging production upon the entire gold industry of California during the entire four years of the war is noteworthy. Throughout the whole period the dredges continued to operate at capacity, and production remained fairly constant around $7,000,000, although a number of enterprises, particularly among the quartz mines,

had to suspend or curtail operations due to adverse condi

tions created by shortage of labor and the high cost of materials.