

THE GRAVEL: NEAR GRASS VALLEY. 



183 



of gravel, clay, and volcanic material, in endless confusion. At a point near the upper end of the 

 ravine, sixty-two feet above the bed-rock just referred to as having been determined by the barom- 

 eter, there is an irregular stratum of gravel varying from seven to fifteen feet in thickness, and 

 into which four tunnels or drifts had been driven. These were all on the same level, and not 

 very far apart. At the time of the examination they were abandoned ; although, as appeared from 

 the condition of the plant, not permanently. 



A little farther west, north of the road to Rough and Ready, is the Rock Tunnel, whose mouth 

 has an elevation of 2,482 feet. This tunnel runs in a direction a little west of south lor a 

 distance of 1,200 feet, and then turning to the left continues on a course a little east of south. 

 The total fall in the tunnel Avas said to be twenty-three feet. An eighth of a mile east of tins are 

 the Lola Montez Diggings, worked by the proprietor, Mr. Weed, in the intervals of ranching, and 

 said to be quite rich in spots. From the Rock Tunnel there is no ravine leading down to Slate 

 Creek, the mouth of the excavation being on the bare hillside. Along this slope, something over 

 a quarter of a mile farther west, are the Jenny Lind Diggings, which are open excavations on the 

 side of the hill, which must have been worked for a considerable time. These diggings were also 

 deserted, although tools were lying about, as if work had been done within a short time. Tun- 

 nels had been run in, and small shafts sunk. The bed-rock exposed was slate. Around the 

 mouth of the tunnel were masses of bluish clay and small boulders of volcanic material. 



At the head of a ravine, about a quarter of a mile in a westerly direction from the Jenny Lind 

 diggings, is the North Star Tunnel, said to have been run in for a distance of about 2,000 feet. 

 Ihe rock at the mouth of this tunnel was slate, having a dip of about 45° to the southeast. There 

 were lava boulders in abundance lying about, which appeared to have rolled down from above. 

 An eighth of a mile still farther west is the Virginia Tunnel, also abandoned, and in 1870 used as 

 a milk cellar, but said to be nearly a mile in length. The measurements at the North Star and 

 V irginia tunnels show that they are both lower than the Rock Tunnel ; but, of the two first men- 

 tioned, the latter is about thirty-five feet higher than the former. 



There are gravel mines near Rough and Ready, three or four miles west 

 of Grass Valley, on the continuation of the channel which passes to the north 

 °f that place. These localities have, however, not been examined in detail 

 b y us, a plan to make Rough and Ready headquarters for some days having 

 been frustrated by want of time. 



At Goshen Hill, at the head of Hawk Ravine, about a mile west of Rough 

 and Ready, a few scattering rounded masses of lava were found, and there is 

 a deposit of gravel, consisting mostly of massive boulders, in which a shaft 

 had been sunk to the depth of forty-three feet to the bed-rock. There 

 appeared to be no indications of a regular channel. The altitude of the 

 *nouth of the shaft is 1,838 feet. 



East of Grass Valley, and probably on the same channel-system which 

 passes that place, but higher up toward the summit of the Sierra, there 

 ar e other localities where hydraulic mining is, or has been, carried on. One 



these is Bannerville, where a tunnel has been run in, under the lava, 

 °n the slate bed-rock. The altitude of the mouth of this tunnel is 2,986 feet, 

 ^d that of the summit of the hill above it 3,231 feet. 



