

AMOUNT AND YIELD OF GRAVEL WORKED. 



119 



whole width of the channel did not exceed seventy-five feet, but which yielded as much as 

 $200,000, which would be over thirteen dollars per square foot of surface of the bed-rock. In 

 this claim it is said that there was in 1851, or 1852, a face of gravel five or six feet in thickness, 

 stretching entirely across the channel, and, to use the miner's expression, "perfectly yellow" with 

 gold. Yet rich as this gravel was, it has not generally paid expenses to hydraulic the top off, 

 after the bottom had been drifted out. In all the spurs crossed by the channel, after leaving 

 Roanoke Gulch, the cement is decomposed and soft, and easily piped, and the banks would not 

 anywhere be more than about a hundred feet in height, if the whole bed of this portion of the 

 Channel were hydraulicked. Consequently several pits have been opened, and the attempt made 

 to wash the whole off; but, as a whole, the work has not even paid " water-money." 



At Wilcox's Claim, on the north fork of Long Canon, the gold is distributed entirely through 

 the gravel from top to bottom. It is both coarse and fine, and generally very smoothly washed, 

 although flaky. The bed-rock surface is not rich, and would hardly pay for drifting. About two 

 acres have been washed off here, and $ 100,000 obtained. 



The proprietor of Flora's Mine, west of Yolcanoville, states that his gravel averages at least two 

 dollars a car-load, and that his claim has yielded about $ 20,000. 



At the Excelsior Claim, near Placerville, about twenty acres of ground have been washed off, 

 with an average thickness of from fifty to sixty feet of pay gravel. The yield from this ground is 

 estimated at over $ 5,000,000, about half of which was taken out by drifting, and the other half 

 by hydraulicking. The whole ridge has been drifted out at two different levels ; first on the bed- 

 rock, and then along a second pay streak which was about twenty feet above this. The latter 

 streak paid about $ 12 per day to the hand, employed. Mr. Alderson, the principal proprietor, esti- 

 mates the yield of the Excelsior gravel at one dollar per cubic yard of dirt washed away ; this in- 

 cludes also the top, which is volcanic gravel. 



It is estimated that the yield of the ground in Coon Hollow, near Placerville, lias been at the 

 rate of live dollars per cubic yard, and that the total amount obtained there is $ 5,000,000. 



16. Amount of Gravel still remaining. 



The distance in a straight line from the outcropping bed-rock a little southwest of the Parker 

 House, at Iowa Hill, to the base of the first Sugar Loaf is some 2,300 or 2,400 feet, and within 

 this distance nothing but gravel is to be seen on the crest of the hill. The Odd Fellows Hall is 

 not far from midway between these two extremities, and the drifting never extended so far south- 

 west as this Hall. As good a rough estimate as can now be made of the total quantity of gravel 

 originally existing, and capable of being hydraulicked, in this ridge, between the first Sugar Loaf 

 and Independence Mill, would be half a mile square, or 160 acres, with an average depth of one 

 hundred feet over the whole of it. The little flat on which stands Independence Hill is about a 

 quarter of a mile long, and it is covered, though not very deeply, with volcanic matter, and the 

 remainder from smaller pits at other points. This would leave between twenty-three and twenty- 

 four million cubic yards yet capable of being hydraulicked. How much of this it will ever pay 

 to wash is a difficult question to answer ; but probably the greater portion of it will be worked 

 with pro li(,, whenever the supply of water shall be plentiful, reliable, and cheap. Such estimates 

 as the above must, however, be considered only as approximations. In this case, the area was 

 calculated from measurements made by pacing, the heights of the banks being determined by the 

 aid of the barometer. There was also as much information obtained as possible in regard to the 

 probable lay of the bed-rock under the gravel, both from personal observation and from the state- 

 ments of men who had worked in the various shafts and tunnels in the region in question, and may 

 possibly bo yet all hydraulicked. This estimate would give, in round numbers, about 26,000,000 

 cubic yards of auriferous gravel in the Iowa Hill Ridge, between the first Sugar Loaf and Inde- 

 pendence Hill. Of this quantity it may be estimated that about 20,000,000 cubic yards were 

 concentrated in the deep channel which crosses the crest at Iowa Hill itself, and the remainder 





