rn 



PILE WASHINGTON RIDGE. 



409 



to Relief Hill, according to my computations, is 330 feet, allowing a grade of only sixty feet to the 

 mile for live and a half miles, somewhat smaller than I had expected to find it. 



The condition of affairs at the time of my visit was one of extreme quiet. No work was going 

 on, the water season being over for the summer. The gravel deposit at Alpha is nearly exhausted, 

 and very little work has been done there for several years. I have not been able to find any allu- 

 sion to the place in either of Browne's or Raymond's reports, which covet the years from 1866 to 

 1875. In early days, as I have been told, Alpha was one of the most "lively camps" in the 

 mountains, with two six-horse stages daily from Nevada City. When I was there I found but two 

 men, who were occupying one of the half-dozen houses still standing. Some work has been done 

 at Alpha the past year, under the superintendence of Mr. J. F. Perry, of Washington. There are 

 several small bodies of gravel left which will undoubtedly pay for washing when water can be 

 obtained at a cheap rate. The original gravel at. Alpha covered an area of, as nearly as I could 

 estimate, seventy-five acres, about four fifths of which has been removed. That which is left is 

 either upon the borders of the deposit, or on its southern side, towards the main ridge. The bed- 

 rock is slate. There are two principal varieties, differing very much in color. One is nearly black, 

 and is cleavable into extremely thin lamina which stand, nearly vertical. The other variety is 

 very light-colored, and is also easily cleavable. The bed-rock lias a gradual fall from east to west, 

 but is nearly level in a north and south direction ; that is to say, there is nothing like a trough or 

 gutter to mark the site of an old channel. On the south side the bed-rock is covered with boul- 

 ders, chiefly quartz, not much worn, .and measuring as much as five or six feet in diameter. To the 

 north the boulders are fewer in number. The gravel at Alpha, where seen in the banks now stand- 

 ing, is light and sandy, growing coarser as the bed-rock is approached, There is no blue gravel 

 to be seen, the lowest layers having a decidedly reddish color. The bank is about ninety feet 

 in height, including twenty feet or so of pipe-clay at the top. The Alpha gravel is said to have 

 yielded better to the cubic yard than that at Omega. The top gold was very fine; but nuggets of 

 considerable size have been found on the bed-rock. 



Between Alpha and the crest of the ridge high bod-rock is to be seen ; the positions of lava, 

 bed-rock, and gravel being represented in the accompanying section (Plate N, Fig. 6), which is not 



drawn to any accurate scale. 



The gravel at Omega lies on a comparatively flat bench of ground, with a rather uneven surface, 

 near the heads of Scotchman's Creek, Missouri Ravine, Baltimore Ravine, and Iowa Ravine, and 

 covered originally, as nearly as I could estimate, about three hundred acres. The bed-rock has 

 been uncovered over about one third of that area. There is a second " high bench " or " back 

 channel," known as Gold Flat, which I have not included in the above estimate. The ridges 

 between the ravines mentioned above rise to an elevation decidedly higher than the top of the 

 present gravel bank, and effectually shut out the possibility of any channel coming in from or hav- 

 ing an outlet in. these several directions. There is also a small patch of gravel between Iowa, 

 Ravine and Missouri Canon, which I did not find time to visit. It lies on the Missouri Canon 

 side of the ridge, and may bo a remnant of an old northeasterly extension of the Omega channel, 



or it may be one of the small and local deposits, some of which are not over fifty feet square and 

 six or eight feet deep, which, I am told, are frequently seen on the spurs leading down to the 

 ri ver. 



The probable position of the old channel above Omega is a matter of doubt. I could see no 

 reason for believing that any of the gravel higher up on the ridge, as, for example, at Diamond 

 Creek, ever had any connection with that at Omega. It is the opinion of some persons that the 

 extension of the old channel is to be looked for under the volcanic tufa to the southeast, the stream 



having come in by way of Gold Flat. Tins upper gravel has not been systematically explored 

 either by tunnels or by shafts, although it has been cut into in places. I made as careful an ex- 

 amination as I could of the surface of the ground in that direction, and failed, to find any strong 



support for such an hypothesis. The existence of bed-rock to the southeast of the town of Omega 



reduces very much the limits within which such a channel must have come, if at all. I am more 



