The Kemp Machine Works of Muncie, Indiana, at one time built several types of air-cooled engines for airplanes, motorcycles, ice boats and air-drives for boats. This Kemp G-2 was one of these engines. It was suitable only for small single-seat airplanes such as Santos-Dumont's Demoiselle and a scaled-down version of Bleriot's Model XI.
Matthew B. Sellers, builder of the first Kentucky-manufactured aircraft, flew his first quadruplane from 1908 to 1913 powered by various 2-cylinder, horizontally-opposed engines such as this.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.