WATER-LINE ON THE ROCKS—-ANCIENT LAKE, 97 
in through the clay very slowly, but appeared to be abundant ; about twenty buckets full were 
obtained in the course of the night. 
November 17.—Deep Well to ide Villages, 13 miles.—Sand hills were observed on the left, 
or north of the trail, for three or four miles beyond the Deep Well, and formed a succession of 
low, rolling hills, or long drifts. For the greater part of the distance this sand did not extend 
to the rocks on the right; thus a clear space was left over which we travelled. The hard floor- 
like surface of the clay formed a good road for our wagons, which scarcely left the imprint of 
the wheels. The sand, in passing over this clay, when driven by the wind, had given the 
surface a fine polish by its attrition. The ridge on the right gradually became lower and 
appeared to be a spur from the mountains. The sky-outline was very peculiar, being extremely 
sharp and irregular, like the teeth of a saw. Such mountains surely merit the name Sierra. 
On reaching the end of this ridge, an unlimited view was presented towards the south and east. 
The broad plain of the Desert was before us, reaching to the horizon. On the right, it was 
bounded by the high mountains which extended down to the plain in successive ridges, one 
beyond another, until their blue outlines could hardly be discerned in the distance. l 
On turning around the point, I saw a discoloration of the rocks extending for a long distance 
ina horizontal line on the side of the mountains. On approaching this, it was found that 
the white color was produced by a calcareous incrustation, extending over the whole surface, 
and into every cavity and crevice. This crust had evidently been deposited under water, and, 
when seen at a distance of a few. yards, its upper margin appeared to form a distinct line, which 
indicated the former level of the water under which it was deposited. This water-line, at the 
point where it was first observed, was only about fifteen feet above the general level of the clay, 
but it could be traced along the mountain sides, following all the angles and sinuosities of the 
ridges for many miles—always preserving its horizontality—sometimes being high up above 
the plain, and again intersecting long and high slopes of gravel and sand; on such places a 
beach-line be could traced. These evidences of a former submergence were so vivid and con- 
clusive that it became evident to every one in the train that we were travelling in the dry bed 
of a former deep and extended sheet of water, probably an Ancient Lake or an extensive bay. 
The shore-line upon our right was distinct and well marked by the incrustation, but the 
opposite shore or boundary ofthe former lake could not be so readily determined ; it must have 
been as far removed as the mountains on the other side of the plain, nearly fifteen miles distant. 
Portions of the calcareous crust were broken off from the rock and found to be cellular and 
easily crumbled, showing that the deposition had not proceeded by successive layers or crusts 
conforming to the surface. In the interstices of the incrustation, and in its mass, many small 
Spiral shells were found ; they were also very abundant upon the surface of the clay, at the 
foot of the rocks, appearing to have been blown into heaps by the wind. They were so numerous 
in some places as to whiten the ground. Five or six species of the genera, Planorbis, Anodonta, 
Physa, and Amnicola, were soon collected, and showed that the former lake was of fresh water. 
These shells were not only on the surface but were imbedded in theclay. They were all white, 
being perfectly bleached, and were very perfect." 
The barometer at the well, having stood at about thirty inches, indicated that we were not 
much elevated above the level of the sea ; ; and the surface had gently descended from that camp 
to this point of rocks and appeared descending beyond as far as wecould see. The view in the 
For a “Article of these shells, and others found on the Desert, see the results of the examination by Dr. A. A. Gould, 
Appendix, Article III. 
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