Lewis/Clark descending Missouri/Yellowstone to reunion — Patrick Gass: July 29, 1806

our voyage from the mouth of Maria’s river; and the current
of the Missouri being very swift, we went down rapidly. At
noon we saw some Ibex or Bighorns at the entrance of a range
of high rough hills; and we halted and killed two of them.
Having dined we proceeded on again, and in our way, during
the afternoon, killed seven more of these mountain sheep.
There are few other animals in this range of high country.
In the evening we encamped opposite the mouth of Slaughter
river, and Captain Lewis had four of these animals skeleton-
ized, to take with him to the seat of Government of the United
States. A considerable quantity of rain fell in the course of
the day.
W ednesday 30th. We embarked early in a cloudy morning
with some rain. In our way through this high range of moun-
tains, we killed four more of the large horned animals, two
buffaloes; two beaver and a bear.
The water of the river is very thick and muddy, on account
of the late falls of rain, which wash those clay hills very much.
We went down the river upwards of 70 miles to day, and
LEWIS AND CLARK EXPEDITION — 269
encamped on a prairie island. Heavy rain fell at intervals
during the day.