This vertical vapor hit n’ miss engine was made by Ron Schindele, of AZ, in 2018. Vapor engines burn fumes that evaporate off the surface of the fuel inside the tank. This usually requires an air and fuel adjustment on the carburetor as well as an air bleed valve in the vapor line from the fuel tank. The bleed valve allows for an air-fuel mixture/to carburetor, and the carburetor allows for the air-fuel mixture/to air intake, for controlling speed. Vapor engines were quite successful in the early days of internal combustion engine development.