Horizontal enclosed crank steam engine with governor

An interesting old horizontal engine, removing the top cover from the fully enclosed crankcase reveals a beautifully made single cylinder engine, robustly built and featuring substantial bronze connecting rod with integral gear driven governor, working by means of a sliding cam. There's a cast oil tray to distribute lubricant, the engine was obviously designed to run for extended periods at high speed with little maintenance.

Free turning, it runs well on air.

Bore 3 inches
Stroke 3 1/2 inches
Length 36 inches
Flywheel 18 inch diameter