her side. These naked, drifting sands gleam
brilliantly in the midday sun of July. The reflected heat from the
glaring surface produces a curious motion of the atmosphere; little
currents are generated and the whole seems to be trembling and moving
about in many directions, or, failing to see that the movement is in the
atmosphere, it gives the impression of an unstable land. Plains and
hills and cliffs and distant mountains seem to be floating vaguely about
in a trembling, wave-rocked sea, and patches of landscape seem to float
away and be lost, and then to reappear.

Just opposite, there are buttes, outliers of cliffs to the left. Below,
they are composed of shales and marls of light blue and slate colors;
above, the rocks are buff and gray, and then brown. The buttes are
buttressed below, where the azure rocks are seen, and terraced above
through the gray and brown beds. A long line of cliffs or rock
escarpments separates the table-lands through which Gray Canyon is cut,
from the lower plain. The eye can trace these azure beds and cliffs on
either side of the river, in a long line extending across its course,
until they fade away in the perspective. These cliffs are many miles in
length and hundreds of feet high; and all these buttes--great
mountain-masses of rock--are dancing and fading away and reappearing,
softly moving about,--or so they seem to the eye as seen through the
shifting atmosphere.

This afternoon our way is through a valley with cottonwood groves on
either side. The river is deep, broad, and quiet. About two hours after
noon camp we discover an Indian crossing, where a number of rafts,
rudely constructed of logs and bound together by withes, are
floating against the bank. On landing, we see evidences that a party of
Indians have crossed within a very few days. This is the place where the
lamented Gunnison crossed, in the year 1853, when making an exploration
for a railroad route to the Pacific coast.

An hour later we run a long rapid and stop at its foot to examine some
interesting rocks, deposited by mineral springs that at one time must
have existed here, but which are no longer flowing.

_July 14.--_ This morning we pass some curious black bluffs on the
right, then two or three short canyons, and then we discover the mouth
of the San Rafael, a stream which comes down from the distant mountains
in the west. Here we stop for an hour or two and take a short walk up
the valley, and find it is a f