12. The Air Vortex Cannon

This video will blow you away. It blew Collin away, literally. Get all the details on how to do this yourself in our book, Experiment 12: Air Vortex Guns and Cannons The Air Vortex Cannon is a giant gun that can shoot a blast of air all the way across a gym. Spook your friends with this invisible surprise, which can mess up their hair or blow out a candle. And then, you can make the invisible visible by sending smoke rings swirling across the room.