Mini Magdeburg Hemispheres

These mini-Magdeburg hemispheres demonstrate the force of air pressure without the need for a vacuum pump. In this modern variant of a famous 17th-century experiment, students place the faces of two hemisphere cups together and squeeze them, forcing out the air between them. Pulling the cups apart is then surprisingly difficult due to the lack of air pressure between them. Each of the 7.5 cm diameter rubber hemisphere has a 2-finger tug handle and 2 release knobs.