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ed and arid condition, which in the summer months now prevents the growth 

 even of their indigenous herbage and grass, and entirely unfits them for agricul 

 ture. We have sought in vain for any valid objection to this proposed use of 

 the water of the stream alluded to for agricultural purposes op the plains be 

 yond the City, as it would be impossible for the waters to escape to any great 

 extent either by evaporation or sinking; which, as it is at present, is the means 

 of robbing the lower bottoms themselves of a sufficiency of water for needful 

 purposes, and leaving the higher terraces entirely parched. The sub-soil of these 

 higher lands, as already observed, is composed of a very tenacious blue clay 

 from 30 to 40 feet in thickness, and as impervious to the percolation of water 

 as a solid mass of granite. The water on reaching the clay will immediately 

 pass into the bottoms through the same avenues which now convey it, and it will 

 have performed its double office of irrigating both the higher and lower portions 

 of the impending surface. A proper and judicious distribution of this stream 

 will, I am convinced, supply abundantly more than three times the area 

 now under cultivation in the immediate vicinity of this City, while the attendant 

 expense would be comparatively inconsiderable. 



ARTESIAN BORING. 



We come now to another means of obtaining water in addition to those men 

 tioned, and as the subject is one of vital importance to the growth and settle 

 ment of large portions of our State, so far as regards its heavier agricultural 

 productions, I shall endeavor to elucidate as far as possible, the principles in 

 volved in the question, and also the probabilities of success in undertaking the en 

 terprise. This of necessity brings us to a detailed examination of the structure of 

 the plain from one extremity to the other, and which will be followed in as concise 

 a manner as possible. 



The City of Los Angeles is situated twenty miles from San Pedro to the 

 north, and has an altitude of 253 feet above tide level, giving an ascending 

 grade of a little more than twelve feet per mile. The level surface of this 

 plain alone will afford no correct idea of its substrata, either in their positions 

 or direction and degree of inclinations, but may serve in some measure as a 

 guide to direct us in making an appropriate estimate of the probable depths to 

 which they descend, and consequently, the probable depth that will be required 

 to sink these wells in order to tap a perennial stream or fountain ; the ultimate 

 depth of boring the artesian wells will depend in part on the thickness and dip 

 of the sedimentary rocks beneath, should it become necessary to pass through 

 them. The stratified rocks composed of sandstones, slates of different kinds, 

 and clays, will first of all demand our consideration, as the position they main 

 tain below the surface, will necessarily affect any process which may be adopted 

 for obtaining water, and this remark will hold good whether the source of sup 

 ply shall rest either above them, among them, or below them all upon the prim 

 itive rocks upon which they stand. 



. In the preceding pages, when speaking of San Pedro, it was observed, that 

 the rocks which form that point, and also Point Fermen were stratified sedi 

 mentary rocks, composed of sandstones, slates, and infusorial deposits between 

 two beds of sandstone, and the whole of these, are on the top of bituminous 

 shales, the bed of which rests conformably upon a bed of very dark arenaceous 

 clay, above which or rather between which and the bituminous shale just men 

 tioned, fresh water is constantly flowing and issuing out. At a much higher 



