Huh... That's an interesting looking thing....
I have no knowledge of it, but looking at it.... I would guess a hand-crank power hammer? Looks like there's a part that moves in some guides on the left side, up and down. That shank on the bottom there makes it look like a hardy tool.... Which, if that's true, would make the anvil terrifyingly huge XD
So... Maybe not the most likely stab in the world... It's just got me pondering, and rambling :P
Is it necessarily related to blacksmithing? Maybe he repaired some portion of something completely unrelated ...