Stuart steam engine model 10 V

This is a Stuart No. 10V model steam engine. It stands about 6" tall and runs great on approx. 5 psi. of air pressure from my air compressor. I like to operate my engines to run slow, but if I turn the air pressure up to 20 psi, it runs so fast that you can hardly see the flywheel spokes. It was built by a friend of mine named Richard. Before retirement, he was a machinist like myself. A great little engine.