Editing Magdeburg Spheres (section)

== Demonstration ==

;Presentation (Stage):
# Show the two halves of the Magdeburg sphere, and that they don't stay together well when you press them into each other. Open the valve on the side of the sphere, and hook it up to the vacuum pump.
# Use the vacuum pump to suck the air out of the sphere, and close the valve on the sphere before turning off the pump. Detach the sphere from the pump, and show that you can no longer pull it apart.
# Ask for two volunteers, and have them each take a handle on the Magdeburg sphere. Have them tug at the sphere to try to open it again, but they can't! Take the sphere from them, and then open the valve to let air back inside. It falls right open!