GEOLOGICAL STRUCTURE. 625 
the land belongs, therefore, to the inner section. It is consequently 
bounded on both sides by snowy summits through a great part of the 
year, the Rocky Mountains on the east and the Cascade Range on the 
west; and at the same time it is nowhere less than a thousand feet 
above the sea. ‘There is good reason, therefore, for its cold, inhospi- 
table character. South of Oregon, the inner section is barren, and is 
well known as the Great Californian Desert. It is properly a semi- 
desert, rather than a desert, as it bears some vegetation over its sur- 
face, though scanty in quantity and useless in kind. It is reported 
to contain some salt and fresh lakes, and to abound in salt efflores- 
cences; but no stream flows from it, as the latest explorations 
show, except the Colorado, which empties into the head of the Gulf 
of California. 
Although Oregon may rank as the best portion of Western America, 
still it appears that the land available for the support of man is small. 
Out of the whole area, about three hundred and fifty thousand square 
miles, only the coast section within one hundred miles of the sea, in- 
cluding in all hardly a sixth of the whole, is at all fitted for agricul- 
ture. And in this coast section there is a large part which 1s moun- 
tainous, or buried beneath heavy forests. ‘The forests may be felled 
more easily than the mountains, and notwithstanding their size, they 
will not long bid defiance to the hardy axeman of America. The 
middle section is in some parts a good grazing tract; the interior is 
good for little or nothing. 
The Oregon territory has great advantages in being the region of 
the Columbia, including both of its widespread tributaries and its 
outlet. ‘The course of this river forms the only pass for merchandise 
from the coast to the interior; the Cascade Range elsewhere is un- 
broken, except by the impassable torrent called Fraser’s River, just 
north of 49°. The trade, therefore, of the whole interior section, from 
the Russian settlements to California, must make use of this channel 
in its way to the sea. 
GEOLOGICAL STRUCTURE OF OREGON AND 
NORTHERN CALIFORNIA. 
The most striking peculiarity in the geological structure of Oregon 
is the abundance of basaltic or volcanic rocks over its surface, both in 
157 
