and late in the evening encamped on its banks. The prevailing timber is a
blue-foliaged ash, (_fraxinus_, near _F. Americana_,) and ash-
leaved maple. With these were _fraxinus Americana_, cottonwood, and
long-leaved willow. We gave to this stream the name of Prairie Dog river.
Elevation 2,350 feet. Our road on the 25th lay over high smooth ridges,
3,100 feet above the sea; buffalo in great numbers, absolutely covering
the face of the country. At evening we encamped within a few miles of the
main Republican, on a little creek, where the air was fragrant with the
perfume of _artemisia filifolia_, which we here saw for the first
time, and which was now in bloom. Shortly after leaving our encampment on
the 26th, we found suddenly that the nature of the country had entirely
changed. Bare sand-hills everywhere surrounded us in the undulating ground
along which we were moving, and the plants peculiar to a sandy soil made
their appearance in abundance. A few miles further we entered the valley
of a large stream, afterwards known to be the Republican fork of the
Kansas, whose shallow waters, with a depth of only a few inches, were
spread out over a bed of yellowish white sand 600 yards wide. With the
exception of one or two distant and detached groves, no timber of any kind
was to be seen; and the features of the country assumed a desert
character, with which the broad river, struggling for existence among the
quicksands along the treeless banks, was strikingly in keeping. On the
opposite side, the broken ridges assumed almost a mountainous appearance;
and fording the stream, we continued on our course among these ridges, and
encamped late in the evening at a little pond of very bad water, from
which we drove away a herd of buffalo that were standing in and about it.
Our encampment this evening was 3,500 feet above the sea. We traveled now
for several days through a broken and dry sandy region, about 4,000 feet
above the sea, where there were no running streams; and some anxiety was
constantly felt on account of the uncertainty of water, which was only to
be found in small lakes that occurred occasionally among the hills. The