Model open crank engine, mounted atop a box which originally contained a 6 volt motorcycle battery (which I threw away because it was full of spiders) and an ignition coil I'm reliably informed is from a Ford Model T. Actually, thinking about it, I was just informed, no idea how reliable the chap is.
Displaying my usual woeful ignorance about infernal combustion gadgets, all I can tell you about this one is there is compression, the inlet valve appears to be an atmospheric jobby opening automatically and it's set up to run on gas. Came from the daughter of the builder, all his other creations were Stuart steam engine based, I could understand those.
Don't know whose design or castings this one was built with - if you can identify it, I'd be grateful.
Flywheels 5 inch diameter