14 
DEPOT CAMP-WALKER^S PASS. 
we came, August 6, to O-co-ya, or Pose creek, seven miles north of Kern river. We learned 
from Godey and others that on Kern river there was no grass, while here we had fine grass in 
abundance. We were now near the head of the valley, and the passes to he examined, and I 
therefore determined to select this point for a depot camp, from which future operations would 
he conducted. 
DEPOT CAMP—FUTURE PLANS. 
O-co-ya creek, at this season, is not here a running stream, hut water in holes is found in 
abundance, and is very good. I am told it never fails entirely. 
My plan was to go with a small party first to Walker’s Pass, and having examined it from 
base to base, to return to the summit, and from thence follow, as closely as the configuration of 
the country would permit, the water-shed, or “ backbone” of the mountains, till I had reached 
the point where the Sierra and Coast range unite. I would by this means be certain of seeing 
very depress on in the mountains. I would then endeavor to ascertain the accessibility of these 
depressions from either base. By this plan I supposed I would gain a good knowledge of the 
general character of the Sierra in this vicinity, and would be able to select judiciously the best 
passes for minute survey. 
The question as to the comparative value of a barometric profile, as compared with one made 
from measurements with the level, was one that had never been answered definitely. We knew 
that the results would not coincide exactly, but the limit of probable error had not been deter¬ 
mined. If, therefore,' I should survey one or more of the passes with both instruments, and, 
comparing the results, find that they agreed closely, it would be presumptive evidence that those 
profiles, made from barometric measurements alone, would agree equally as close; whereas, if 
a great disagreement was found, it would shew that the barometric profiles were not reliable. 
For these reasons I resolved to run a line of levels, from base to base of the Sierra, through one or 
more passes, as the results of the preliminary reconnaissance might determine. I was aware that 
this would occupy several weeks; but as the bearing of the result would not be upon the one pass 
only, but upon every one examined during the survey and perhaps upon the barometric profiles 
of the other parties whose extended lines did not permit them to use the level, I believed the 
time could not be devoted to a better object. 
While the preliminary examination was going on, the wagon-train was to return empty to 
Fort Miller, to obtain a further supply of provisions and barley, and Lieutenant Stoneman, 
with that portion of the escort not otherwise engaged, was to remain in Depot camp to guard 
the stores and other property left there. 
On the morning of August 10, the wagon-train started from Fort Miller ; and I, accompanied 
by Lieutenant Parke, Mr. Smith, civil engineer, Mr. Preuss. draughtsman, Mr. Godey, as 
guide, and five men of my party, started for the passes in the mountains. We had an escort 
of a corporal and nine men. We carried with us two barometers, besides the aneroid, a sextant, 
and the other usual instruments for a surveying party. In giving the result of the reconnais¬ 
sance, I will, for more convenient reference, separate it under different heads, according to the 
pass to which the particular part may refer. 
WALKER’S PASS. 
Upon leaving camp we followed up Pose creek till it took a bend coming from the northeast, 
when we left it and took up a dry branoh, with here and there a spring, our general course 
