This engine was described in the May 1881 edition of Scientific American and was listed under Amateur Mechanics as a "Simple Single-Acting Steam Engine".  Drawings were discovered  plus a basic description of the engine and some key dimensions.

One feature was the use of brass tubes for the cylinder and piston that would telescope together thus saving having to bore the cylinder and machine a piston on a treadle lathe that it was assumed most amateurs at the time would have. It was said to be approx 1/20 HP and had a bore of 1.5" x stroke of 2" and an 8" flywheel.

Drawings were made to suit some thick wall brass tube that I had for the cylinder and that dictated that I use a 19mm bore so my metric design is about half size. I also altered some of the construction methods suggested, and added a bit more elaborate detail so that I would not make it too quickly.

MEWS plans to include a description of the fascinating machining processes that were used in the build.