8 
GENERAL DESCRIPTION OF COUNTRY. 
commanding general of the division. In fine, all the preparations were completed, and the 
party ready to leave Benicia, on the 10th of July. 
GENERAL REMARKS. 
Before proceeding to give a detailed narrative of our work in the field, I think it would tend 
to a more clear understanding of the subject if I were to give a concise description of the great 
topographical features of the country about to he examined, and the main objects, as I under¬ 
stood them, to be attained by this survey. 
Benicia, the depot where the party was fitted out, is the northernmost point mentioned in my 
instructions. This town is situated on the Straits of Carquines, through which the waters of 
the Sacramento and San Joaquin rivers flow into San Francisco hay and the Pacific. From 
these straits to the southward, following the general course of the coast, is a range of moun¬ 
tains, extending beyond the southern boundary of this State into the peninsula of Lower 
California. This range often presents the appearance of several ridges, sometimes parallel, 
sometimes nearly at right angles ; but there is one line, or water-shed, nearly parallel to the 
coast, and distant from it from 50 to 70 miles, which is unbroken by any water-course from San 
Francisco bay to Lower California. From this water-shed numerous short streams flow, mean¬ 
dering between the spurs or secondary ridges of the one great and continuous range, and 
forming rich and fertile valleys. This range varies in height from 800 to 5,000 or 6,000 feet. 
It is generally known as the Coast range, and this will be understood as its meaning where this 
term is used in this report. 
If from Benicia we travebdue east for about 120 miles, we will be at the summit of a much 
higher range than the one last mentioned, and following its water-shed southwardly, we find it 
gradually approaches the coast, until, in latitude 35° 20' N., it actually joins itself to the Coast 
range, and the two are blended into one. 
This is the Sierra Nevada, and varies in height from 4,000 to 8,000 and 10,000 feet. These 
mountains have a numerous population of miners, and though they have not been examined 
instrumentally but at two or three points, they have been so thoroughly “prospected” by the 
miners, that it is well known in the latitude of Benicia they are high and rugged, whereas near 
their junction with the Coast range they are much lower. 
Mr. Blake considers the mountains south of this point of junction as the prolongation of the 
Sierra Nevada rather than the Coast range, and in his report he has proposed the name Bernar¬ 
dino Sierra for that portion of the chain extending from the end of the Sierra Nevada to the 
peak of San Bernardino. 
Between the western base of the Sierra and the eastern base of the Coast range is the vast 
plain of the San Joaquin and Tulare valleys, being 300 miles long, and averaging 65 miles in 
breadth. These valleys are well watered by numerous streams flowing from the Sierra, though 
not one of consequence reaches them from the Coast range. The result of this is, that the 
traveller going along the western side of these valleys will find no stream, while on the eastern 
side he will find one every few miles. In the southern part of the plain are several lakes, called 
the Tulare lakes, and hence this part receives the name of the Tulare valley; while farther 
north, the San Joaquin river, eoming from the Sierra, flows through the middle of its valley—a 
continuation of the other—in a northwest direction, receiving numerous tributaries from the east. 
To the east of both the Sierra and Coast range, the country is very little known, and very 
