Collier's New Encyclopedia (1921)/Missouri (river)

MISSOURI, a river of the United States; formed in the Rocky Mountains, in Montana, winds circuitously along the base of the mountains, then E. till it reaches the W. boundary of North Dakota and receives the Yellowstone. Here it begins to flow S. E. through North and South Dakota, then forms the E. boundary of Nebraska, separating it from Iowa and Missouri; separates for a short distance Kansas from Missouri, then strikes E. across the latter State, and joins the Mississippi after a course of 2,908 miles. It is navigable 2,500 miles from the Mississippi.