Three-cylinder homebuilt radial engine from 1922. It is exhibited at the Air Venture Museum and the photograph is courtesy of Gary and Janett Brossett, from the Aircraft Engine Historical Society.

"Doll"

-The Doll engine was built by farmer Frank Doll in Marshall, Illinois. He made the molds in wood and took them to the Indiana Terre Haute foundry. Then he mechanized it in his farm's workshop.