38 PASSES OF THE SIERRA NEVADA. 
flats. It is true, there is a small sheet of water upon the surface of a small portion of the 
most eastern of them, and upon the most southwestern also; but their general character 
is precisely that of the Desert west of Great Salt lake—a plain of mud, more or less miry 
at intervals, destitute of vegetation, with a surface, especially when recently moistened by 
rain, presenting at a little distance a perfect resemblance to a sheet of water. It is here 
and there incrusted with salt, but not to the extent of the desert referred to. The first 
branch of these plains which we crossed was 6.90 miles in width. At this point we crossed 
Frémont’s trail of 1844, leading from the Boiling springs to Pyramid lake. We then travelled 
along the north end of one of the ranges or spurs of mountains terminating in these plains. 
I experienced great difficulty in ascending it a few hundred feet on horseback, its composition 
being in many parts precisely that of the plain, into which, of course, it is washed by every 
shower. Granite is, however, found in the same mountain, and vegetation in some parts, but 
there is none upon the friable surface. It was late in the day when we arrived on the eastern 
border of the second branch of the plain, and it was very doubtful whether we could cross it. 
There was no alternative but to try it, however, and sleep in the mud if we failed; for, although 
on a lake, we were without water, nor could any sign of it be discovered, nor of grass. Taking 
a few men with me, therefore, I at once set off, leaving the party to follow with Captain Morris, 
if I should not turn back in a short time. But although the road was heavy, we experienced 
no difficulty in crossing this branch of the lake for ten miles to the foot of the Sierra Nevada. 
The sun was bright, although the day was very smoky, and the reflection severe upon our faces 
and eyes. When in the centre of the plain, we were gratified by the sight of bushes and of 
green vegetation in the mountain we were approaching, indicating the position of springs and 
of small streams; but the streams did not reach the lake, and we experienced much difficulty 
in ascending to them, as they were upon a terrace, in front of which the ascent was very steep, 
and so covered with blocks of trachytic rocks, that it was only after great exertion that our 
were driven over them to water and grass. We were here upon the Noble road, which 
follows the north shore of the lake by the Boiling springs. In descending to Mud lake north, 
from the valley east of our morning camp, the grade is 76.60 feet per mile for 11.75 miles, 
and thence to our present camp, or indeed to any point upon the borders of these plains, the 
change of level is merely nominal. Day’s march, 25.27 miles; altitude above the sea, 4,118 
feet. 
June 15.—I remained in camp to-day to refresh our animals and give the party rest, its 
severe labors from sunrise until sunset every day, and frequently until midnight, with the 
men on guard every third or fourth night, requiring relaxation. 
June 16.—In order to discover a practicable railroad pass, if possible, in the Sierra Nevada— 
this portion of which had never been explored—I determined to examine every opening and 
depression which could be seen to the east, commencing with the northern, and proceeding 
towards the south—determining not only the merits of each, but establishing their comparative 
value. The first of these openings we reached by turning gradually westward three miles south 
of our last camp, and crossing a branch of Mud Lake valley, 8.85 miles to its foot. I there 
entered a level, narrow ravine, varying from 50 to 200 yards in width, and more or less winding 
for six miles. Its walls are precipitous, and at a few points vertical. Large rocks lay scattered. 
about its bed, preventing its use by wagons, and ours were sent further to the north over the 
hills, but descended to the creek to encamp, having marched but 15.20 miles; our ascent by 
the course of the stream being but about 200 feet above Mud lake. The mountains here are 
thoroughly trachytic, and many of the rocks partake of a volcanic character—black, red, and 
white in color, and porous in their formation. 
June 17.—Fallen rocks, thick willows, and a miry soil prevented us from following the 
ravine, the sides of which were also difficult to follow, being constantly broken by side ravines, 
as deep ; and nearly as large as the main branch—the rocky sides of which vary from 50 to 200 
feet in height, and are too steep to be ascended on horseback. But as its course was sufficiently 
