William Henry, of Pennsylvania, tried a model steamboat on the Conestoga river in 1763. 威廉·亨利·杜利特.世纪发明.
To simplify his fishing expeditions he made a model of a boat propelled by paddles, and later he built such a boat and used it on the Conestoga River. 鲁伯特·萨金特·荷兰.历史性发明.