Missouri River near Little Missouri — Patrick Gass: April 19, 1805

not set out until the next day. While we lay here, I went out
to the hills, which I found very high, much washed by the
rain, and without grass. I saw a part of a log quite petrified,
and of which good whetstones—or hones could be made. I
also saw where a hill had been on fire, and pumice stone
around it. There is a great quantity of hysop in the vallies.
We killed an elk and some wild geese, and caught some
beaver.