e
Mississippi. Leaving at length the great western plain, we begin to
mount the slopes of the Rocky Mountains, when we may gaze upwards at the
lofty snow-covered peaks above our heads. Hence, crossing the mighty
range in spite of grizzly bears and wilder Indians, we descend towards
the bank of the Rio Colorado, which falls into the Gulf of California,
and thence over a mountainous region, some of whose heights, as Mount
Dana, reach an elevation of 13,000 feet, and Mount Whitney, 15,000 feet.

THE FOURTH ZONE.

The southernmost of the four zones begins on the coast of Florida,
passes for hundreds of miles over a low or gently sloping country toward
the great western plains which border the Rocky Mountains into Texas;
its southern boundary being the Gulf of Mexico. Through this region
flow numerous rivers, the queen of which is the Mississippi. The
western portion is often wild and barren in the extreme, inhabited only
by bands of wild and savage Indians. The Rocky Mountains being passed,
there is a lofty table-land, and then rise the Sierras de los Nimbres
and Madre; beyond which, bordering the Gulf of California, is the wild,
grandly picturesque province of Sonora, with its gigantic trees and
stalactite caves.

PART ONE, CHAPTER THREE.

THE PRAIRIES, PLAINS OF THE WEST, AND PASSES OF THE ROCKY MOUNTAINS.

To obtain, however, a still more correct notion of the appearance of the
continent, we must take another glance over it. We shall discover, to
the north, and throughout the eastern portion where civilised man has
not been at work dealing away the trees, a densely-wooded region.
Proceeding westward, as the valley of the Mississippi is approached the
underwood disappears, and oak openings predominate. These Oak Openings,
as they are called, are groves of oak and other forest-trees which are
not connected, but are scattered over the surface at a considerable
distance from one another, without any low shrub or underbrush between
them.

THE PRAIRIES.

Thus, gradually, we are entering the prairie country, which extends as
far west as the Grand Coteau of the Missouri. This prairie region is
covered with a rich growth of grass; the soil is extremely fertile, and
capable of producing a variety of cereals. Over the greater portion of
the prairie country, indeed, forests of aspens would grow, did not
annual fires in most parts arrest their progress. Here and there
numbers have sprung up. The true prairie r