If you have a plague of domestic mice, then catching them humanely and walking them to a safe new home around the corner is not an option.
Today’s invention is a new multi-kill mousetrap which is powered by a mouse.
1. A mouse is attracted to the cheese (orange) placed beside the exercise wheel (pink) in a box. He runs on this for a while and a gear train (dark blue) allows the wheel and platform to rack-and-pinion (pale blue) its way upward.
2. As the platform rises, other mice can wander in towards a second piece of cheese on the floor of the box.
At a certain height, a catch is released, allowing the platform to fall down on whatever mice are below.
The whole system is ready to run again at once, assuming occasional removal of dead mice and replenishment of bait.