In 1854 he became Indian agent at Taos, New Mexico, in which position, through his knowledge of the Indian traits and language, he was able to exercise for many years a restraining influence over the warlike Apaches and other tribes.
In 1820 he accompanied General Lewis Cass as geologist in his expedition to the Upper Mississippi and the Lake Superior copper region, and in 1823 he was appointed Indian agent for the Lake Superior country.
In 1832, as colonel, he took part in the Black Hawk War, and was the officer to whom Black Hawk surrendered; later he occasionally acted as Indian agent along the upper Mississippi.
