6 THE AURIFEROUS GRAVELS OF THE SIERRA NEVADA. 
of the Coast Ranges as well as the lines of drainage have a corresponding 
direction. The Santa Iiiez Mountains rise here boldly from the coast to the 
height of 4,000 feet, while to the north of this range and parallel with it 
runs the river of the same name. North of this, again, we have the broad 
chain of the San Rafael Mountains, which connects at its eastern end with 
the Sierra Nevada. The Santa Maria, or Cuyama, River, whose course is in 
general near the 35th parallel, forms the boundary between the east and 
west and the northwest and southeast trending features of the Coast Ranges. 
The east and west trend of the Santa Ifez Range is continued through 
Ventura into Los Angeles County in the Sierra de San Fernando, and parallel 
with this latter, in close proximity to the coast, and on the 34th parallel is 
the Sierra de Santa Monica. Their eastern terminations are lost in the great 
mass of mountains which, with a southeast trend, extend on through the 
southern portion of California, and which are known by various names in 
their various subdivisions, as the San Gabriel, the San Bernardino, and the 
San Jacinto ranges. 
North of the Bay of San Francisco, we find as far as Clear Lake, in the 
parallel of 39°, a general parallelism of the topographical features with the 
trend of the coast, the drainage being chiefly in a southeastern direction 
into the Bay of San Pablo. The ranges are much broken, however, in this 
portion, Napa Valley being the only depression of considerable length ex- 
tending parallel with the coast. North of Clear Lake there is one pretty 
well marked dominating ridge, which holds a general parallelism with the 
coast, trending with it more to the northward; and, after passing the parallel 
of 40°, actually bending round a little to the east of north, as does the coast 
between Cape Mendocino and Crescent City. The drainage, however, from 
the main divide is in the direction of parallel lines having exactly the same 
trend as that portion of the coast between Punta Arena and Cape Mendocino. 
Kel River, a little over a hundred miles in length, is the principal one of the 
streams. A notice of the character of the drainage of the Coast Ranges as 
related to the Great Valley will be better introduced after a sketch of the 
topography of the other great system of mountains on the eastern side of 
that valley, 
The unity of the Sierra Nevada is at once apparent in the single name which 
it bears, in marked contrast with the Coast Ranges. No one has ever thought 
of dividing the Sierra into groups with different names; while on the other 
