JF Ptak Science Books Post 1096
I think perhaps one of the oddest places to find a locomotive is in the inside of a propeller of a ship on the high seas.
This image really belongs to the sub-category "Out of Place Department", along with the unexpectedly-found restaurant at the top of a punked-out 19th c Eiffel Tower, a swimming pool in the bottom of a mine shaft, a steamboat along the side of a mountain in Amazonia, and so on. Seeing this strange sea craft and the cutaway schematic showing the man-sized locomotive (and tender) was very exciting and unexpected as well, perhaps more so than most of the unexpected steam/electro punky thingsa that I come across.
It appeared as a real-life suggestion as "Chapman's Roller Vessel" in (ca.) 1897 and looks o be a squarish, blocky ship of questionable seaworthiness, fitted out with two hollow cylindrical props powered by two small small-gauge locomotives running infinitely on small-gauge tracks inside of them, push-pulling the ferry through the water. (I wonder about access to the engine and how to control its stopping and starting; I would only hope that there wasn't someone at the locos' controls.)
It seems to me to be a bad idea of a high order.