It appears like it must have fire in it. It has small air inlet and no exhaust. It was produced by Dietzgen. They make surveying and drafting gear.
There's a huge steel valve with a lever that controls a flapper in the bottom. A bulge in the tin cover lines up with the word CLOSE on the casting to leave the flapper closed.
It was in a thrift shop listed as a hand warmer. I doubt it.
Anyone have a clue?