65 



The fossil drift beneath the conglomerate east of the plain is not perceptible to 

 that extent which would guide us to any conclusion as to the depths to which it de 

 scends at the edge of the valley. Therefore no estimate is entered for this deposit 

 in this table. 



The survey of the U. S. Kail Road Expedition, for 1854, has demonstrated that 

 the fossil deposits of this range of country, are continuous to the extreme southern 

 portion of the Tulare plains. The fossils of Pose Creek appear identical with 

 those of the counties of Placer and Sacramento, but I am unable to give their 

 differences in altitude if any exist, as the observations which would determine that 

 point, are not accessible at the present time. 



Between the Tulare plains and the American River, there are some fou or five 

 other localities in which the tertiary deposits have been observed, and which con 

 tain imbedded fossils closely allied to those found in the localities specified ; and the 

 evidences thus furnished in relation to this subject are very conclusive in their char 

 acter, as pointing to that period when the Tertiary seas had their boundaries far to 

 the east of their present limits. A recession of the waters of the Pacific Ocean 

 has therefore taken place, to the distance of 140 miles, since the period at which 

 those fossils lived. A suite of these specimens for the State collection has been 

 secured, from this very interesting portion of the State, a list of which will be found 

 appended to this report. 



We have now a more practical and economical view to take of this subject, so 

 far as relates to the positions of these beds, and as this will involve a pecuniary in 

 terest in which the mining community are directly concerned, I solicit their partic 

 ular attention, as well as that of the State authority, to the subject. 



In order that a better understanding of the position of these rocks may be ob 

 tained, the following table showing their natural and relative positions is inserted. 

 It commences at a point due north of Beale's Bar and continues west to the ends 

 of the plains : 



Beale's Bar, 

 Texas Flat, 

 Slates, 



Conglomerate, 

 Fossil Beds, 



Mfeet Shaft. 



JLlder Springs, 



Conglomerates, 



Fossil Beds, 

 Granite. Granite. Granite. 



Plains 



From the above table it will be seen that the 94 feet shaft which was sunk on 

 whut is familiarly known as volcano ridge in the county of Placer did not reach 

 that point at which the drift deposit containing gold may be expected to occur. 

 This is proved by the fact that at Alder Springs, a short distance to the west, t'le 

 basis rock is granitic, and the auriferous deposit is found lying upon it, and belo 7 

 the conglomerates and fossil beds to the east. The same fact is noticeable at tw > 

 other mining localities to the south and west of Alder Springs, also in the flats som > 

 three miles to the north of Beale's Bar. There are then at least five diflerent posi 

 tions at which the fossil beds are known to lie above the auriferous drift, and ths 

 positions assigned to the beds under consideration in the table furnish the data on 

 which to found the conclusion. They occupy the terraced positions as occurring afc 

 the points designated, denudation having caused the outliers to the west of Aldar 

 Springs. Similar peculiarities are also noticeable in some of the lower minin 5 

 localities further to the south, where the workable placers are found to occupy alikj 

 position among the hills a few miles east of the plains. 



The position of those beds as they are found to occur in the lower hills, and where 

 also the best opportunities are offered for their study, leads us to the conclusion thai 



