The Bathtub was developed by Etienne Dormoy, a French engineer at McCook Field in Dayton Ohio. 

The aircraft used a steel tube fuselage, with an exposed tail section. The parasol wings used wooden spars with fabric covering supported by steel lift struts. The ailerons used steel control cables that were exposed in front of the leading edge of the wing. The engine was a modified Henderson motorcycle engine purchased for $325.
The Dormoy Bathtub competed in the 1924 and 1925 National Air Races, winning the Rickenbacker Trophy in 1924. 

 

Source: http://en.wikipedia.org/wiki/Dormoy_Bathtub