Desmoines, a town of the U.S., capital of Polk county, and of the state of Iowa, on a river of the same name, 350 miles W. of Chicago. The town contains some good public buildings, and possesses extensive manufactures. There are coal mines in the neighbourhood. Desmoines River rises in a group of lakes in the S.W. of Minnesota, and flows S.E. for 300 miles into the Mississippi, four miles below Keokuk. It is the largest river of Iowa, and for 20 miles above the junction it forms the frontier between Iowa and Missouri.