I think this is a marine engine and I suspect it is an aluminium crankcase
too. I do see what you mean about a Lister top end, Mark, but the whole
thing is only 15" high, so it can't be, can it?
Patrick Knight might have some ideas.
Looks like a hand held bingo callers ball cage to me :-))
As it has what looks like a high voltage or frequency electrical
connection of some sort at the bottom and what looks to be a "Faraday
Cage" at the top, could it be a nuclear scientists version of a "Lava
Lamp" with the radium giving off charged particles like sparks
visible in dimmed light? If so,...I want one!!!!! (:-))
Anything to do with X-Ray or Gamma-ray NDT weld testing? As I recall
this involves wrapping a film round the outside of a welded joint in a
pipe and putting a radioactive source inside the pipe for a period to
create an image of the porosity or not of the weld.