All I can tell you is that it is a really amazing machine ... but you already knew that!
I will add that the geared reversing system is unlike anything I have ever seen, and the ornate spoked flywheel likewise is something that I've never seen.
It seems odd to me that it is a single acting engine, as it is set up in such a way that it would take nothing more to make it double acting and thus almost twice as powerful.
Perhaps you will never know the who, what, where, why of this particular engine, but that doesn't make it any less amazing in my mind!!!