ANIMAL-TRAP.
Suspended barbed hooks that pierce the animal's neck and throat.
The trap hangs by a chain from a tree, with a V-shaped spring holding a movable hook-bar cocked against a stationary hook-bar. Bait is placed on a shorter bait-hook; when the animal pulls it, the sear releases the trigger-catch. The spring snaps the movable bar downward, driving its barbed hooks into the back of the animal's neck while the stationary hooks enter its throat. The two sets of hooks interlock and the animal remains suspended.
“As the hooks are barbed it will be apparent that an animal once caught can never release itself. While I have described this trap as adapted for catching animals, it is to be understood that the same principle may be applied for trapping fish, the only change required in the structure being to make it smaller.”— David S. McCollum, from the specification
And the world did not beat a path to his door.