THE WASHINGTON RIDGE. 



415 



ridge or mass of bed-rock to obstruct the view. It seems most probable that this portion of the 

 gravel field represents a broad estuary or lakelike expansion of water at the junction of two streams 

 or where two streams, by the filling up of their channels and the covering of the low intervening 

 ridges, became practically one. If this latter view is correct, it is not impossible that there may 

 once have been a current from Grizzly Hill towards Columbia Hill, even if the slope of the deep 

 bed-rock is in just the opposite direction. 



Above Sailor Flat there are other deposits of gravel whose relations I did not take the time to 

 study in detail, though I was very glad to take advantage of Mr. Chad wick's kind offer to spend 

 a part of a day with me in a visit to some claims in New York Canon, about two miles east of 

 Sailor Flat. Beyond this, and distant about half a mile, is Meeker's Canon, which is followed, a 

 mile farther east, by Lane's Canon. 



A complete profile section of the ridge from the river to the crest of the lava would show, first, a 

 quite steep ascent, for two thirds or three quarters of the way, to a bench or flat, a half-mile or 

 more in width, across which the ascent is much more gradual, and then a second steep pitch to the 

 top. Along this bench or flat there are some surface indications of the existence of gravel below. Some 

 of the indications are seen in the ditches, which are for the most part in the volcanic tufa, but with 

 occasional exposures of clay and line gravel, lying underneath the tufa. The marshy and swampy 

 character of portions of this bench, especially in the winter, point to a substratum of clay, such as 

 is usually found accompanying the gravel. The present surface dirt is to a great extent a volcanic 

 wash which prevents any immediate examination of the supposed clay and gravel excepting at 

 some expense. The wash is not a part of the main lava-flow, for there is a considerable belt of 

 bed-rock here and there visible to the south of the bench or Hat before the steep lava-cap is 



reached. 



In the year 1875, or near that time, Mr. Chad wick, in company with others, began the sinking 

 of a shaft in New York Canon at a point below all the ditches and fully half a mile from the crest 

 of the ridge. The mouth of the shaft is near to and on the left bank of the water-course in the 

 canon. I made the altitude of this point to be 3,149 feet. The first twenty feet of the shaft were 

 in volcanic cement; below this there was as much as a hundred feet or more of clay and sand, 

 with no gravel to amount to anything ; and after this a stratum of clean, washed quartz gravel 

 was penetrated for thirty feet without reaching bed-rock. The inflow of water was so great that 



further sinking was given up for the time. The position of this gravel is peculiar in this respect : 

 to the west of the shaft there is high bed-rock, at least seventy-five feet higher than the mouth of 

 the shaft, which shows that the gravel cannot be regarded as a portion of any deep-lying east and west 

 channel. Possibly it has come into its present position through the action of the New York 

 Canon waters alone, though its depth from the surface affords a strong argument against that 

 supposition. 



Easterly from this shaft, at a distance of nearly a quarter of a mile, on the spur between New 

 York Canon and Meeker's Canon, I saw rolled quartz gravel on the surface, some sixty feet higher 

 than the mouth of the shaft, and Mr. Chad wick assured me that similar gravel could be seen at a 

 point a quarter of a mile farther to the southeast, and at an altitude of from fifty to seventy-five 

 feet above the point last mentioned, but I did not have the time to extend my observations any 

 further in that direction. A mining company, of which the secretary is Mr. E. W. Bigelow of 

 Nevada City, holds a claim of 500 acres in this vicinity, which will probably not be developed as 

 long as the banks lower down need the amount of water they do at present. 



I will close this section of my report with a few notes upon Round Mountain, which were given 

 me by Mr. Hughes, who is personally interested in the gravel mines at that locality. Round 

 Mountain is a lava-capped knob about three miles to the southwest of Blue Tent. The "channel " 

 is on the northerly side of the ridge, and is 340 feet higher than the bed-rock at Gopher Hill. It 

 has been explored by a shaft and by a tunnel. The shaft reached bed-rock at the distance of 

 eighty-five feet from the surface. The first thirty feet were sunk through "soil"; the remainder 

 through layers of coarser or finer pipe-clay and sandy gravel. The tunnel is at the lower end of 



