ANIMAL TRAP
A spring jaw trap whose trip plate pivots to various angles.
The operator compresses the bow spring and drops its ring over lugs on the base, holding two pivoted hooked jaws in a horizontal position. A trigger arm is lowered onto one jaw and caught in a notch of a lever supporting the trip plate. The animal bears down on the trip plate, which releases the trigger from the notch. The spring expands upward and draws the hooked jaws closed about the game.
“When it is desired to trap game, the simple form of combination of the parts enables the trap to be easily concealed from the view of the game as it approaches, and thus presents advantages in use.”— William Cooper, from the specification
And the world did not beat a path to his door.