A small coal-fired multi-tube test boiler, it came in some years ago as a part-exchange with a great boxful of stuff and has languished on the shelves since. It's only Claire's dogged persistence in tracking down its stock number and taking some photographs which has led to its appearance here today.
From what I remember of this one it was made up from a kit, possibly the Kennions design through don't quote me on that. Mainly silver-soldered with some evidence of soft soldering, standard of work looks pretty pedestrian throughout. Complete with fittings, it will need a test before use.