Taylor Fur Getter trap gun - photo

[clavius]

Looks like a down the throat device. Bite the meat, trigger the hammer.

That was close to the idea. The hook was the trigger and you would bait it with a piece of meet as you mentioned. I'd read about these before but the link in the orignal post has some interesting info. Apparenltly, you could set how high it shot above the hook (low for small animals, higher for larger ones) such that it would deliver a point blank shot directly to the animals head. That would quickly kill the animal (even with the small .22 round) and also not cause damage to the pelt, as these were developed during the height of the fur trade.