"Soda Bottle" Steam Engine

I restored this little 4" bore by 5" stroke steam engine and gave it to the Museum of Alaska Transportation and Industry. I dug it out of a mud bank and it was solid rust. It was used to power one of the coal feed augers (Archimedes screw) in the coal washing plant at Sutten, Alaska. The plant burned down in 1919. It runs great on air and, hopefully, on steam one of these days.