148 PHYSICAL GEOGRAPHY.

 

of the Gulf Stream, immediately beyond it. In Figure
125, the dotted lines show the successive steps of the
formation.

386. Forms of Relief—The United States is
traversed by two distinct mountain-systems: the
Pacific System—the predominant system—on the
west, and the Appalachian System—the secondary
system—on the east.

387. The Pacific System, consists of a broad
plateau, traversed by two distinct mountain-sys-
tems: the Rocky Mountains, and the Pacific
mountain-chains. It embraces about one-third
of the entire territory of the United States
proper.

388. The Rocky Mountain System, consists of
a number of parallel chains connected by numer-
ous cross ranges. They rise from the summits of
an elevated plateau, which in some places ‘is fully
7000 feet above the sea. The chains are broken
in several places by transverse valleys or passes,
traversed by important rivers. The most import-
ant of these passes is South Pass, in Wyoming,
traversed by the Sweet Water. River, a tributary
of the Platte. The Missouri, Rio Grande, and
other rivers also flow through similar depressions.

The chains are separated into northern and southern
sections by a gap occupied by an elevated plateau, over
which the Union Pacific Railroad passes.

Among the many lofty peaks of this mountain-
system are Long’s Peak, 14,050 feet ; Pike’s Peak,
14,216 feet ; and Fremont’s Peak, 13,570 feet high.

A remarkable feature of these mountains is the basin-
shaped valleys, called parks, formed by transverse ranges
connecting the parallel ranges.
these parks are North, South, and Middle Parks. They
are nearly rectangular in outline, and are hemmed in by
huge mountain-ranges. Each park gives rise to an im-
portant river. The rich verdure of these deeply-sunken
basins is rendered the more striking by contrast with the
desolate mountains surrounding them.

The Yellowstone National Park, in the north-western
part of Wyoming, is traversed by some of the head-waters
sof the Yellowstone River. It is a region of hot springs,
deep gorges, high mountain-peaks, and magnificent scenery.
It has been set apart by the government for the purposes of
a public park.

The Great Plains, an elevated plateau, lie
along the eastern side of the Rocky Mountains.
They are undulating plains, which slope by
almost imperceptible gradations, to the valley
of the Mississippi. They are treeless, and near
the base of the mountains have but a scanty
vegetation. Near the lower part of the slope
they merge into prairies, covered with a luxuri-
ant growth of grass. r

 

 

The most important of |_

389. The Pacific Mountain-Chains extend
through California, Oregon, and Washington,
and, in general, are parallel to the Rocky Moun-
tains. They comprise the Cascade Mountains in
Oregon and Washington, and the Sierra Nevada
and the Coast Mountains in California.

The famous gold regions of California lie mainly west
of the Sierra Nevada and the Coast Mountains.

The loftiest peaks of the Pacific Mountains—

chain exceed those of the Rocky Mountains in
height. The highest peaks are Mt. Rainier in
the Cascade Range, 14,444 feet high; and in the_

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4 e

Sierra Nevada Range, Mt. Shasta, 14,482 feet —}*

high, and Mt. Whitney, 14,800 feet high.

The eee point of the Pacific Mountain-
chains is MouaSt=kes, in Alaska, which is es-
timated to Be 19, 500 feet high.

The Cascade Mountains contain numerous ex-
tinct volcanoes.

The Great Basin lies between the Wahsatch on the east.
and the Sierra Nevada and Cascade ranges on the west,

 

 

 

Fig, 126, The Great Gatton 0 of Colorado,

It possesses a true inland drainage. East of the Wahsatch
Mountains and the western flanks of the elevated peaks

 

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