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SUPPLEMENTARY INVESTIGATIONS IN THE GRAVEL REGION. 



The country to the north of Fall River, including the gravel of Franklin Hill and Cammel's 

 Peak, I made no attempt to explore. From the descriptions I received of those places, I thought 

 my time could be employed more profitably elsewhere. The only important deposits of gravel in 

 this vicinity that I passed by -without examination were those of Saw Pit Flat, Richmond Hill, 

 and Washington Hill near Onion Valley. I got a glimpse of the diggings, and a general view of 

 the course of Onion Valley Creek, from the stage-road on my way from La Porte to Quincy. Had 

 I not been travelling by stage, I could have made a stop of a few hours, and thus have seen some- 

 thing of the details of the situation. It did not seem worth while to make a stop of three days at 

 Onion Valley for the sake of so little. The chief interest of these deposits lies in the possibility 

 of their representing an upper portion of the same old channel, whose lower course can be traced 

 from Hepsidam or La Porte down the valley of Slate Creek. My own opinion, based, however, 

 upon imperfect observations, is opposed to any hypothesis of that kind. It seems to me that the 

 Onion Valley gravels stand by themselves, quite distinct from any of the more southern channels. 

 Indeed, I may go farther, and say, as the final generalization from all the observations I was able 

 to make on both sides of the divide, that I can see no reason for regarding the gravels in the region 

 drained by the Feather River as in any way related to those in the basin of the Yuba. The pres- 

 ent dividing ridge between the rivers is a boundary which was equally well-marked at the time 

 the gravels on either side were deposited. 



B. Quincy and Vicinity. 



The region to be described in this sub-section lies to the north of the Middle Fork, and south of 

 the east branch of the North Fork of the Feather River. I approached it by stage from La Porte 

 by way of Onion Valley. In the preceding sub-section I gave the altitude of the summit of the 

 road near Onion Valley as 6,430 feet. From that point there is a very rapid descent down the 

 canon of Nelson Creek to the Middle Feather at Nelson Point. The rock exposed along this por- 

 tion of the road is almost entirely a very thinly laminated slate. The altitude of the bridge across 

 Nelson Creek I made to be 4,120 feet ; that of the bridge at Nelson Point, 3,950. Along the road 

 between the river and Quincy I saw, at frequent intervals, considerable detached volcanic rock ; 

 though the prevailing rock, so far as it could be recognized, was slate. I could not fix the relations 

 of the two to each other, but I was satisfied that the so-called " Little Volcano," near Nelson Point, 

 has nothing to do with igneous phenomena. 



Near Nelson Point there is good evidence that the Feather River once flowed in a deeper 

 channel than it does now. On the northern bank of the stream there is a small gravel deposit, in 

 which, as I was told, a shaft has been sunk to a depth of fifty feet below the present river-bed. 

 A quarter of a mile northerly from the river the stage-road crosses a belt of lava cement, in which 

 a shaft has been sunk to a reported depth of 350 feet without reaching bed-rock, though a high 

 rim of such rock is seen cropping out only a short distance farther along on the road. The general 

 belief is that this deep channel is traceable from Bell's Bar to Nelson Point. I did not learn any- 

 thing about the character of the gravel ; its position shows that it can have had no connection 

 with the so-called "high gravels." 



The gravel deposits which lie within a few miles of the town of Quincy, to the north, west, and 

 south, present a great many puzzling geological questions, the solutions to which cannot be reached 

 in a hasty reconnaissance of a week. It is very evident, for instance, that the topographical 

 features of the country have been much changed since the date of the deposition of the earlier 

 gravels. There is not that harmony between the former and the present systems of drainage 

 which is so prominent a feature in parts of Sierra and Nevada counties. In some cases, indeed, 

 the direction of drainage is precisely reversed. It is also evident that the gravel deposits do not 

 in all cases, if in any, antedate the flows of volcanic rock ; and that some of them, at any rate, are 

 of comparatively recent origin. Some of the older gravels may, very likely, have been subjected to 

 a re-arrangement, or a re-deposition, in connection with the changes of surface topography. From 

 these statements it will be seen at once that the problem here presented to the geologist is quite 





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