LETHAL TRAPPING DEVICE
Poison bait sealed in a tin can, sold in six-packs.
A small tin can of the frozen-juice type contains a cake of poisoned bait fixed at one end and a one-way entrance of flexible plastic fingers at the other, hermetically sealed until use. The user opens the far end with a can opener and slides on a square cardboard collar, torn from the six-pack carton, to keep the can from rolling. The mouse pushes inward through the fingers to reach the bait; the fingers resist outward deflection and the mouse cannot exit. The mouse eats the bait, dies, and the entire can is thrown away.
“Nibbling the bait, the rodent is quickly dispatched with a minimum of suffering and is disposed of trap and all.”— James S. Hellen, from the specification
And the world did not beat a path to his door.