The San Francisco call., 1898-01-23
THE GOLDEN GRAVEL
OF CALIFORNIA.
BY JOHN HAYS HAMMOND.

Prior to the gold excitement in Cali fornia and Australia in the years 1S4S and 1851, respectively, the estimated quantity of gold in circulation in the world was from 5000 900, 900 to $2,500 O00,OOO. Since the commencement of this golden era it has been computed that the worlds gold circulating me dium has been increased by the intro ductiOn of about 4.500, GOO, coo
 The great part California has played in the addition to the worlds wealth will be recognized when it is said that fully one-Quarter of this increase has been derived from the gold mines of that State. Of the entire gold produc- tion of California, not less than nine tenths has been yielded by the 'aurif- erous gravels." :"
 The total yield of the auriferous gray els of California would be represented by the value of a cube of pure gold having an edge of fourteen feet Over $100,0 100000 has been invested in the gravel mines of California.
 The auriferous gravels may be divid- ed into two classes:
 First-The shallow or modern placerS.
 Second-Deep or ancient placerS.
 These terms are indicative of the very characteristic difference that eX- ists between the two classes of placers.
 The signification of these terms will be apparent from an explanation Of the origin and mode of occurrence Of the placerS. These placers are superficial accumulatiOns of auriferouS alluvions along the gulches, bars, flats, etc, and are designated gulch, bar or flat dig gings, according to their typographical position. The deposits along the mod ern rivers belong to the shallow piacers.
 The gold bearing detritus of which they consist has been derived from the ancient placers or the quartz veins; in some instances from both sources. Through the disintegrating and trans porting power of the mete ic agencies, especially of running water, the ma terial has been brought from the above sources, and redeposited in places or lower elevation, where it was discov- cred by the pioneer miners. Thus the asserting process has been carried, by natural agencies, one step farther than in the case of the deep or ancient pla- cers, and two steps farther than in the formation of the gold-bearing quartz veins. To this process of the higher concentration of the gold is due the ex- traordinary richness of the shallow pla- cers
 From the shallow placers, and from the beds of the modern rivers, came nearly all the gold produced by Cali fornia up to the year 1854, and indeed the larger percentage up to the year 1860. The exhaustion of the gold gray els, capable of being worked with profit by such primitive means as were avail able at that time, led to the abandon ment of the shallow diggings.
 The unworked deposits, also, often occur below the drainage level.
 The pan and cradle. especially the former, are still used for the purpose of prospecting or testing the gravel, and for cleaning up the sluices. batter ies, etc, at all mines.
 River mining by sluices, rockers. etc, is now almost entirely limited to the operations of the Chinese, several thou sands of whom. scattered over the State, follow the business in a desultory way. A few of the bars of the present rivers are still being worked by wing dams" by which aA periods of low so as to leave dry the gravel deposit
 In several localities. Butte and Pla- cer counties principally, plans are be-