Purely out of interest we would like to know what this thing does.
It was found in my grandmothers house. Her husband/man friend (weird relationship stuff blah blah blah) used to be a cabinet maker and often made caskets too. I believe he used to make model boats as a hobby but have never seen any.
It wouldn't have been touched in over 20 years since he died and appears to slide over something. Moving the central 'cage' moves the arm across the scale from 0 to 10.