The Great Can Crush is a demonstration of the strength of atmospheric pressure. A 55-gal drum is filled with about 3 inches of water. A propane burner is used to boil the water. After about 30 minutes, a clear trail of steam is coming out of the drum. The drum is then capped off and ice is placed on the top. The steam inside the drum condenses leaving the drum partially evacuated. The atmospheric pressure collapses the drum to the surprise and delight of the spectators!
