Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 5, Pt. 2

SHARK'S TEETH-POSUNCULA RIVER.
August 28.-We were visited by several Indians from Posuncula river. They brought a fish,
weighing about three pounds, and dressed deer skins for sale.
August 29 and 31.-Examined the lithological character of several of the hills about camp, and
obtained sections. On the tops of two of the hills opposite camp a great number of shark's
teeth of different sizes were found lying loose on the surface, having been washed out by the
rains. Fragments of bone and of fossil wood were also procured. The elevation of these hills
above camp is about 500 feet, according to the aneroid barometer.
OCOYA CREEK TO TiTHE TEJON.
Ocoya Creek to Posuncula River, September 1-10.8 miles.-The road or trail connecting Ocoya
creek with Posuncula river winds about among the rounded Tertiary hills already described, and a
fine view of the almost innumerable ravines and gulches that furrow their sides is presented.
The remarkable steepness of the slopes is also very distinctly seen along this trail, the
inclination often becoming 35~, so steep that it was impossible to ascend without first cutting a
foothold. Several land slides were also observed, where great hills appeared to be cut down
through the centre, exposing all the lines of stratification on the face of a vertical bluff. These
slides probably take place in the rainy season, when the soft clay and porous strata become
soaked with water, so that their weight is very much increased. The material which thus
breaks away from the hills is in a condition to be rapidly acted on by running water, and is
quickly removed to the lower grounds. The trail for the greater part of the distance between
the two streams follows the bottom of one of the ravines or water courses; it is, of course, very
tortuous, and- in some places is so narrow that the wagons were forced to travel partly upon the
slopes of the hills. A sketch by Mr. Koppel presents a good view of the hills along a part of
this ravine, and serves to give a good idea of the general character of the hills near, our camp on
Ocoya creek. (See View X, Chapter XIII.) Posuncula, or Kern river, like Ocoya creek, has
a nearly westerly course for a short distance after leaving the granite ridges of the Sierra. It
also traverses the belt of Tertiary foot-hills, and makes good natural sections of the strata along
VALLEY OF POSUNCULA RIVER.
its banks. The section it forms on its southern or left bank presents an interesting appearance
when viewed from the tops of the hills, at the divide between its waters and those of Ocoya
creek. The bank is seen to extend many miles, with a nearly uniform elevation above the
stream, presenting an even outline like the edge of a table land or terrace. It is, in fact, the
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