* * QUINCY AND VICINITY. 477 
The gold occurs principally on the bed-rock, the top gravel being poor. That which comes directly 
from the gravel is coarse; the gold of the underlying ledge is finer. The average fineness of the 
Mumford Hill gold is .945. Since the deposition of this gravel there has been a fault or a slip 
in the bed-rock amounting to at least six feet. The fault is traced up through the gravel by 
means of a clayey slickensides, the face of which is smooth and striated with parallel lines. It 
was not easy to secure specimens which would show these markings, and at the same time be firm 
enough to bear transportation. That this really marks the place of a crevice in the gravel is 
further shown by the presence of rootlets of trees to a depth of twenty-five feet below the surface 
of the ground, —a depth several times greater than that to which these rootlets make their way in 
the undisturbed gravel. The strike of the fault or slip corresponds very closely with that of the 
bed-rock. 
From Mr. Edman I obtained a small quantity of concentrated sands from Rock Island, a gravel 
deposit the precise position of which I cannot give. These sands have been examined micro- 
scopically by Mr. Wadsworth, who says of them: “ The white crystals here are zircons, the majority 
having the form figured in Dana’s System of Mineralogy, page 273, except that the crystals are 
longer and the prismatic planes correspondingly developed. Magnetic iron is abundant. Some 
pale greenish fragments occur, which may possibly be broken augites. A grain or two of rutile 
was seen.” 
Between Mumford’s Hill and the toll-gate on the stage-road from Quincy to Oroville the trail 
crosses Eagle Gulch and Deadwood Gulch. Between these two gulches lies Sead Point, “ scad” 
being in miner’s parlance the equivalent of nugget. The Scad Point gravel is about a third of a 
mile north of Mumford’s Hill, but is nearly 200 feet lower, the altitude of its bed-rock being only 
4,510 feet. It is evidently more recent in origin than the gravel of Mumford’s Hill, for it contains, 
together with a little quartz and some clay, a large proportion of volcanic material and representa- 
tives of the country rock which is found in places in the near vicinity. The bed-rock has been 
designated as a “ greenstone porphyry,” and forms part of a belt of similar rock, which can be 
traced for several miles in a northwesterly direction. The grade of the channel is from east to 
west, or directly towards the high escarpment of Spanish Peak. The thickness of the gravel is, 
on the average, nearly fifty feet. The gold is said to be distributed through the whole mass. In 
the beds of Eagle Guleh and Deadwood Gulch gold used to be found as far up as their intersec- 
tion with the two gravel deposits last described ; higher up, the gulches were poor or barren. On 
the toll-gate ridge, as I was informed by Mr. Edman, there is a small gravel deposit, supposed to 
be on the continuation of the Scad Point channel, in which further evidence of faultings of the 
country rock, since the formation of the gravel, may be found. I did not visit the locality. 
The country, for five or six miles along the eastern base of Spanish Peak, between the stage-road 
and Chaparral Hill, is said to contain several gravel deposits, of greater or less extent and of doubt- 
ful date and uncertain origin. It is a district of which, on account of the abundance of vegetation 
and the infrequency of good exposures of rock, but little can be learned in a hasty trip of a few 
hours. I went as far as Tucker’s Ranch, at the head of Scales’s Gulch, where the altitude is 4,100 
feet. Near this point, according to Mr. Tucker's statement, there are two old channels, running in 
different directions. A third channel, at an altitude several hundred feet higher, is supposed to 
exist near the base of Spanish Peak. Further evidence of faulted bed-rock is reported from a 
tunnel in Scales’s Gulch. These interesting points had to be left without further examination on 
account of lack of time. ' 
The lower portions of this district, about Meadow Valley and Spanish Ranch, are covered, over 
hundreds of acres, with gravel to an unknown depth. The low grade of Spanish Creek prevents 
the application of the hydraulic process in the mining of these gravels, and the accumulation of 
water in the workings would probably make shaft-sinking and drift-mining unprofitable. 
From the previous descriptions it can he easily seen that the gravel problem in the vicinity of 
Quincy is not the same as it is in the country south of the Feather River. Irregularity takes the 
place of a comparative uniformity ; a much-broken, faulted, and disturbed bed-rock, the place of 
