



U A I IU4IUJ MiU HPIH PP 





72 



THE AURIFEROUS GRAVELS OF THE SIERRA NEVADA 



tude, on the main ridge as well as on spurs of them, and even on isolated 



peaks."* 



The current opinion of the Californian miners in regard to the origin of 



the high gravels, at the time of the beginning of the State Geological Survey 

 under the direction of the writer, is probably very well stated by Mr. Hittell 

 himself, and reads as follows : " The alluvial placers may be divided into 

 ancient and modern. The ancient are those formed by streams which no 

 lono-er exist, or have found new channels. Two very remarkable examples 

 of the ancient stream placers are found in California ; one called the Blue 

 Lead of Sierra County, the other Table Mountain in Tuolumne County. It 

 is supposed that the Blue Lead was once the bed of a large river, about fifty 

 miles eastward of the present position of Sacramento River and parallel with 

 its course. Table Mountain is a pile of basalt, standing on what was, in the 

 remote past, the bed of a river nearly parallel with the Stanislaus. These 

 ancient and deserted channels are not rare, and are found from a very small 

 to a very large size. They are usually buried at a considerable depth be- 

 neath dirt and gravel. Sometimes they are found high above the level of 

 the present streams running near them."t This statement of Mr. Hittell 

 is much nearer the truth, as now made out from a long series of careful 

 examinations by the Geological Survey, than anything which had been pre- 

 viously published, and contrasts in a marked degree with the crudities con- 

 tained in the official report of a French mining engineer. 



The essential fact that the high gravels of the western slope of the Sierra 

 Nevada have to do with an ancient river system having been so clearly recog- 

 nized by many of the miners, it is not difficult, from the stand-point of our 

 present knowledge of the conditions in which they occur, to understand why 

 this view did not meet with universal acceptance. It was always hampered 

 with the idea that there was one great river running parallel with the crest 

 of the Sierra, as we see in the quotation just given from Mr. Hittell's book. 

 As long as this determination to change the whole present condition of the 

 drainage system of the Sierra was persisted in, without accounting in any 

 way for such a change ; as long as a river forty miles in breadth had to be 

 imagined, in order to embrace all the deposits in question, and regardless of 

 the fact that one of its banks would have to be some thousands of feet higher 

 than the other, so long of course the ancient river theory would continue to 



* Quoted in Hittell's Mining in the Pacific States, pp. 74, 75. 

 f 1. c. p. 63. 



