This came als a lens cap with the old 12x10" Butcher lens (see other thread about that lens: https://www.largeformatphotography.i...=1#post1570081) ...however as you instantly see this is no lens cap, and I'm just wondering what it might be - part of an old car / old jug ?

this is how it came to me:



here some close up pictures;
diameter of the big part is about 80mm / 3.25 inch







In the cap at the top under the cover/lid there are 3 tiny screwholes.