9. Egg in a Bottle

Watch air pressure in action by placing a peeled, hard-boiled egg on the mouth of a glass bottle. Light a small piece of paper, drop it inside, and quickly set the egg on top. As the flame uses up the oxygen, the air pressure inside drops, and the higher outside pressure pushes the egg into the bottle.
This dramatic demonstration reveals the power of atmospheric pressure. It can be compared with the classic crushed can experiment, which also uses pressure differences to create surprising results. For full instructions, see the Exploratorium Egg in a Bottle guide.

