Baldpated prairie, from a ridge of naked hills which bound it, running
parallel with the river as far as we could see, and from three to six
miles distance. To the south the hills touch the river. We encamped a
quarter of a mile beyond this, in a point of woods on the north side.
The river continues to fall.

Tuesday, July 17. We remained here this day, in order to make
observations and correct the chronometer, which ran down on Sunday. The
latitude we found to be 40° 27' 5"4/10. The observation of the time
proved our chronometer too slow, by 6' 51"6/10. The highlands bear from
our camp, north 25° west, up the river. Captain Lewis rode up the
country, and saw the Nishnahbatona, about ten or twelve miles from its
mouth, at a place not more than three hundred yards from the Missouri,
and a little above our camp. It then passes near the foot of the
Baldhills, and is at least six feet below the level of the Missouri. On
its banks are the oak, walnut, and mulberry. The common current of the
Missouri, taken with the log, is 50 fathoms in 40", at some places, and
even 20".

Wednesday, July 18. The morning was fair, and a gentle wind from
southeast by south, carried us along between the prairie on the north,
and Bald island to the south: opposite the middle of which, the
Nishnahbatona approaches the nearest to the Missouri. The current here
ran fifty fathoms in 41". At thirteen and a half miles, we reached an
island on the north, near to which the banks overflow; while on the
south, the hills project over the river and form high cliffs. At one
point a part of the cliff, nearly three quarters of a mile in length,
and about two hundred feet in height, has fallen into the river. It is
composed chiefly of sandstone intermixed with an iron ore of bad
quality; near the bottom is a soft slatestone with pebbles. We passed