SANDSTONE NEAR SAN AMEDIO—RETURN TO CAMP. 45 
operations, and it is probable that the ore used in the furnace was obtained from the debris in 
the ravine. 
After obtaining specimens of the ore and the adjoining rocks, we returned to the camp-ground 
of the previous evening and again encamped. 
September 22.—We returned towards the Cafiada de las Uvas by the same trail, and, soon 
after leaving camp, passed the great outcrop of sandstone strata seen on the afternoon of the 
20th. The highest part of this series of strata was estimated to be over five hundred feet above 
the level of the creek. "The accompanying wood-cut will show the character of the strata and 
their inclination. 
INCLINED STRATA OF SANDSTONE NEAR SAN AMÉDIO. 
Several observations on the dip were made with the clinometer, and angles, varying from 45? 
to 50°, were obtained. The colors of the strata are various; the lower beds are red, being 
highly colored by oxide of iron. A coarse conglomerate is found among the lower beds on the 
opposite side of the creek, the stones being from three to six inches in diameter, and much 
rounded. The same bed is probably found in the lower parts of the strata represented in the 
engraving. Nearly all the strata are argillaceous sandstone, in layers of varying thickness. 
It was impossible to remain in that vicinity long enough to give these outcrops a careful,and 
critical examination. I searched for fossils, in the hope of determining the age of the formation, 
but without success. It is much more consolidated than the Miocene formation along Ocoya 
creek, and the disturbed and uplifted condition of the strata indicate a different age. The lower 
one OMNCM n v AN S TECTA etl ری افش‎ 
