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156 



THE AUEIFEEOUS GEAVELS OF THE SIERRA NEVADA. 



At Missouri Hill the surface of the bed-rock exposed is not large, neither was the amount of 

 gravel considerable. All that is left is an abundance of boulders, of such form and dimensions as 

 to remind one strongly of the upper end of the Dutch Flat claims. There are many sharp corners 

 and edges visible, which may be owing to the fact that a good proportion of the boulders have 

 been broken since they were uncovered. 



At Little York proper — that is, east of the bridge of ground left standing, along which the road 

 to You Bet crosses — there is a large extent of gravel. At the deepest part is a channel, from one 

 to two hundred feet in width, of hard, blue gravel, — in some places almost " cement/' — and in 

 which are numerous boulders of considerable size. The depth of this blue gravel it is not easy to 

 give with precision. At the lower end of Scott's Ravine the stratum between the blue and the 

 overlying red gravel consists of a sort of clayey sandstone, which is six or eight feet in thickness, 

 and appears to pitch to the west, at an angle of 8° or 10°. Above the blue channel is a depth of 

 from 125 to 150 feet of a finer red gravel, and this is spread out over a broader area, the bed-rock 

 rising pretty rapidly on the south side, to a point about twenty-five feet above the level of the 

 town at the flag-staff, so as to form a well-defined trough of red gravel at least GOO or 700 

 feet wide at the top. From that point the bed-rock still rises, but more gently, toward the 

 south, for a quarter of a mile or more, in the direction of Manzanita Hill. The rock, especially 

 in its upper portion, is a clayey slate, which decomposes very rapidly when exposed to the action 

 of air and water. At some points it was difficult to tell whether one was standing on the bed- 

 rock, or on a mass of clay belonging to the gravel series. As a rule, the uppermost gravel of 

 Manzanita Hill is quite fine, of a reddish color, and easily washed away. There are also strata of 

 clay to be seen in it, which attain, on the eastern side of the hill, a thickness of six feet or more. 

 These strata are seen to dip toward the southwest, at an angle of from 12° to 15°, which is about 

 the position they might have been expected to assume if they were deposited on the sloping side 

 of a bay or indentation between two hills, to one side of the main channel of the river. A nearly 

 north and south section across the Little York gravel is represented on Plate F, Fig. 3. This 

 figure is drawn so as to include the gravel on Christmas Hill, which will be described a little far- 

 ther on. The position of the small narrow and deep channel, at d in the centre of the section, 

 will be observed, as well as the broader channel of red gravel, extending from c to e. The summit 

 of Manzanita Hill is at /, and that of Christmas Hill at a, the position of the bed-rock surface 

 under the last-named elevation being unknown, but probably, as represented in the section, sloping 

 to the south. The upper line representing the original surface of the gravel is, of course, only an 

 approximation. 



At Empire Hill there is, at the bottom and middle of the channel, a mass of blue gravel thirty or 

 forty feet in depth. Its general direction is east and west, but the drifting under the easterly bank 

 shows that the course of the channel was not exactly straight from Scott's Ravine to Empire Hill, 

 but that there was a slight bend around to the north. The southern bank of Empire Hill is nearly 

 washed away ; but on the northern one there is, above the blue gravel, a thickness of thirty or 

 forty feet of red, the succession being the same as at Scott's Ravine. Toward the west end of 

 Empire Hill boulders of from one to three feet are common. They are found mostly in the upper 

 thirty feet of the gravel, and many of them are quite angular, the corners being hardly rounded 



at all. 



The main mass of the Christmas Hill gravel covers a surface about three quarters of a mile long 



and an eighth of a mile wide ; or, in round numbers, about sixty acres, the longer axis having a 



nearly north and south (magnetic) direction. It is on the top of the ridge which separates Steep 



Hollow from Bear River, and is about midway between the two streams. The county road from 



Little York to Liberty Hill follows this ridge, and for half a mile is quite near the bank of gravel ; 



for some portions of the way, indeed, there are openings on both sides of the road, with just width 



enough between to allow teams to meet in safety. The top of the Christmas Hill is pretty flat, 



although sloping gradually from the highest point toward Rear River, Steep Hollow, and Little 

 York, as far as the gravel extends. Then, on both sides, the pitch into the two canons is quite 



