 As a result, the US was then free to expand westward out of the Ohio valley and into the Great Plains and the Southwest.The success of the "Charlotte Dundas" in Scotland in 1801 and Robert Fulton's "Clermont" on the Hudson River in 1807 proved the concept of the steamboat.At this time, walking beam mill engines, of the Boulton and Watt variety, were dropped onto wood barges with paddles to create an instant powerboat.