21 



portion of the ancient banks still remain on the south side of the mountain for 

 about one mile in length, and this is found to rest on the same micaceous schist 

 that is found at various points, as before mentioned. The drift is composed of 

 the debris of primitive rocks alone. 



Within the outcropping mica schist on the flanks of the mountain and beneath 

 the basaltic mass, is found a very modern aqueous deposit, consisting of clay, 

 sands, fine and coarse gravels, similar in all respects to present river beds. 

 Among these are found the shells of alosmodon and a few small univalves, the 

 casts of which closely resemble some forms of physa present inhabitants of the 

 adjoining streams. Of the former shell I am unable to distinguish it from alas- 

 modon yubaensis, a shell found in all our streams throughout the State at the 

 present time. 



The fine clays contain an abundance of leaves of present existing genera and 

 species, most of them may be found in the adjacent country distributed along 

 the banks of the streams and in the deep ravines adjoining. 



The " bed rock " is primitive, like the present baiik of the Stanislaus to the 

 north, being composed of mica schist and the older trappean group. Time is yet 

 required to determine with certainty the period to which this basaltic overflow 

 belongs, but from present appearances it seems improbable that it should extend 

 beyond the pliocene. 



The examination of the fossils, made by Messrs. Evans, Shumard and Newb.erg, 

 about the Dalles, and other parts of Oregon and Washington Territories, may 

 throw some light upon this subject, as these gentlemen have observed the overflow 

 of basalt in those regions over the modern aqueous deposits to an extent that 

 would make " Table Mountain " a mere secondary affair. 



The gravel arid clay beds of this locality have been found to prove extremely 

 rich in placer gold, but like all. new discoveries of this kind, much that has been 

 said is only conjectural. 



There is good reason to believe that the range will furnish a large amount of 

 gold, from one extremity to the other, as it flows over a deposit which has been 

 derived from the primitive rocks exclusively, from which the greater portion of 

 the placer gold of this State has been set free. 



Another reason that confirms this opinion is found in the fact, that the drift 

 deposits which lie beyond the western terminus of the Table Mountain, and 

 inferior to the same, are well charged with gold. They are likewise co-extensive 

 in an easterly direction with the mountain, so far as that limit is at present known. 



This being the case it will require no dangerous tension of the mind to believe 

 that for many years hence, this district will yield ample rewards for labor, though 

 in a minor degree to what either anticipation or report would make it. 



This mountain has been often blended with the table lands that skirt the base 

 of the Sierra Nevada in many places. There is but one locality with which I am 

 acquainted, that bears any resemblance to it, and that is in the vicinity of Pose 

 Creek on the Upper Tulare. The relationship here existing is found in the 

 character and age of the material, but not in the forms that it assumes; for in the 

 latter case the overflowed matter is mostly scoriaceous and massive, and not 

 prismatic. 



The table lands (called Table Mountains since the opening of the locality at 

 Sonora) of other parts of the State are the remains of the ancient shores of the 

 ocean, and are of marine origin exclusively, having their origin from aqueous 

 causes alone, not from igneous. The peculiarities of form seen from a distance, 

 has been the cause of confounding them together. 



Beneath the basaltic rocks of the Table Mountain, and below the fresh water 

 deposits that immediately succeed the latter, are found a series of marine tertiary 

 rock, composed of sand-stone, conglomerate and slates regularly stratified, and 



