ese steps, you may descend by a gentle, sometimes
imperceptible, slope to the foot of another. They thus present a series
of terraces, the steps of which are well-defined escarpments of rock.
The lateral extension of such a line of cliffs is usually very
irregular; sharp salients are projected on the plains below, and deep
recesses are cut into the terraces above. Intermittent streams coming
down the cliffs have cut many canyons or canyon valleys, by which the
traveler may pass from the plain below to the terrace above. By these
gigantic stairways he may ascend to high plateaus, covered with forests
of pine and fir.

The region is further diversified by short ranges of eruptive mountains.
A vast system of fissures--huge cracks in the rocks to the depths
below--extends across the country. From these crevices floods of lava
have poured, covering mesas and table-lands with sheets of black basalt.
The expiring energies of these volcanic agencies have piled up huge
cinder cones that stand along the fissures, red, brown, and black, naked
of vegetation, and conspicuous landmarks, set as they are in contrast to
the bright, variegated rocks of sedimentary origin.

These canyon gorges, obstructing cliffs, and desert wastes have
prevented the traveler from penetrating the country, so that until the
Colorado River Exploring Expedition was organized it was almost unknown.
In the early history of the country Spanish adventurers penetrated the
region and told marvelous stories of its wonders. It was also traversed
by priests who sought to convert the Indian tribes to Christianity. In
later days, since the region has been under the control of the United
States, various government expeditions have penetrated the land. Yet
enough had been seen in the earlier days to foment rumor, and many
wonderful stories were told in the hunter's cabin and the prospector's
camp--stories of parties entering the gorge in boats and being carried
down with fearful velocity into whirlpools where all were overwhelmed in
the abyss of waters, and stories of underground passages for the great
river into which boats had passed never to be seen again. It was
currently believed that the river was lost under the rocks for several
hundred miles. There were other accounts of great falls whose roaring
music could be heard on the distant mountain summits; and there were
stories current of parties wandering on the brink of the canyon and
vainly endeavoring to reach the