In 1938, “Beilgard Mechanical Research Laboratory”, based in Hollywood CA, made a nine-cylinder, barrel-type engine that curiously ran on butane gas.

-An experimental barrel type engine built in California by H. Belgard from the Mechanical Research Laboratory.

-It had nine cylinders around and parallel to the main shaft.

From appendix A5/6: We obtained a photograph of H.A. Beilgard with his aero engine. It was presented in Hollywood, California.

"The Beilgard together with its inventor" (PiP)