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exert a beneficial or injurious effect upon operations that will be presented in the 

 improvement of the soil in this part of the country. 



The dip of these rocks is peculiar in some respects, following as they do a di 

 rection different from that which might have been anticipated, from any features 

 which the relative positions of the mountains and plains present on their exter 

 iors. We should expect to find a linear dip from the mountains to the sea, 

 where the inclination of the surface is so regular from the former to the latter ; 

 but in place of this we find that the dip of the stratified rocks is the reverse of 

 this, inclining to the east, while those of the mountain ranges directly opposite 

 are found inclining to the west. Were these peculiarities limited to a small 

 area they might be accounted far from local causes acting in such immediate dis 

 tricts, but as we find them extending along the coast-line for a distance of nearly 

 250 miles, we cannot but regard them as the results of extensive local action, 

 elevating the coast-line. 



There is but one other method of accounting for the position of the rocks, 

 (extending as they do from the southern shores of San Simeon to the northern 

 lines of the counties of San Diego and San Bernardino,) which is, that the Is 

 lands forming the west coast of the Santa Barbara channel were originally uni 

 ted and formed part of the main land, holding those relations to the plains at 

 the east, that the coast mountains do to the valleys of the Sacramento, Salinas 

 and Santa Clara. There may be some reason for a supposition of this kind, as 

 many of these islands contain quiet elevated lands, and the island of Catalina 

 is in reality an almost unbroken mountain ridge, (with the exception of what is 

 called the Isthmus,) for 30 miles in length, as elevated as many parts of the 

 coast mountains. 



Should this position be assumed, we must suppose that an area of plain lands 

 equaling three-fourths of the length of the Sacramento and San Joaquin valleys 

 by about 200 miles in breadth, (for these islands extend through four degrees of 

 longitude and nearly six and one half degrees of latitude) must have been sub 

 merged during one or a succession of those turbulent periods that have formerly 

 been in existence on the western portion of this continent, or that a rupture hav 

 ing occurred, the inroads of the seas have gradually denuded these lands, and 

 thus effaced them. 



It would be unnecessary to travel thus far into the abyss of time, to reconcile 

 a feature that may present itself, like that under consideration, where we have 

 an agent at hand, in active operation, and adequate to produce all the features 

 whhh these rocks manifest ; more simple and satisfactory will it be to account 

 for their present dip by the agents above alluded to, than to seek for causes be 

 yond our comprehension and our powers of satisfactory demonstration. 



In an economical view these rocks will claim our attention. It has been obser 

 ved that the rocks on the coast-line for the most part have an easterly dip while 

 those of the mountains to the east dip in an opposite direction. The effect of 

 this is to produce a basin-shaped structure, under the surface of the plains and 

 as this section of the State is strictly agricultural and but little improved, it be 

 comes an inquiry of no little importance to ascertain the probabilities that exist 

 for obtaining water through artesian borings. 



The structure of the rocks which form the basis of the plains of Los Angeles 

 are such that we may reasonably suppose that subterranean waters are flowing 

 among the slates and compact sandstones beneath the surface. The character 

 of these rocks should first be understood and also their positions relative to each 

 other. 



