While searching the web looking for things of interest and ran onto this gadget, which is a demonstrator of James Booth's 1843 invention of a "rectilinear" linkage or mechanical motion that was intended to be used on a compact steam engine. Apparently there are no records that such an engine was ever built. However more recently English model builder Anthony Mount ran onto the patent drawings and designed a scale model. It is the model shown to the right on the cover of his book shown below.
This project started by making a wood pattern and pouring castings. While I was at it, I also poured castings for the next intended project.
This was a simple project with few parts, but still took several days. Yesterday it became operational, and this morning it received a little paint and a wood base. Although it is interesting to watch the movement, I do not know how practical it would be in a steam engine. I'm sure my model will end up being another desk toy.