overflowed, and judging from the customary and notorious changes in the
river, a few years will be sufficient to force the main current of the
river across, and leave the great bend dry. The whole lowland between
the parallel range of hills seems formed of mud or ooze of the river, at
some former period, mixed with sand and clay. The sand of the
neighbouring banks accumulates with the aid of that brought down the
stream, and forms sandbars, projecting into the river; these drive the
channel to the opposite banks, the loose texture of which it undermines,
and at length deserts its ancient bed for a new and shorter passage; it
is thus that the banks of the Missouri are constantly falling, and the
river changing its bed.

August 6. In the morning, after a violent storm of wind and rain from
N.W. we passed a large island to the north. In the channel separating it
from the shore, a creek called Soldier's river enters; the island kept
it from our view, but one of our men who had seen it, represents it as
about forty yards wide at its mouth. At five miles, we came to a bend
of the river towards the north, a sandbar, running in from the south,
had turned its course so as to leave the old channel quite dry. We again
saw the same appearance at our encampment, twenty and a half miles
distant on the north side. Here the channel of the river had encroached
south, and the old bed was without water, except a few ponds. The
sandbars are still very numerous.

August 7. We had another storm from the N.W. in the course of the last
evening; in the morning we proceeded, having the wind from the north,
and encamped on the northern shore, having rowed seventeen miles. The
river is here encumbered with sandbars, but no islands, except two small
ones, called Detachment islands, and formed on the south side by a small
stream.