Fill an olive jar or some other tall thin jar with water and cover the open end of the bottle with a piece of plastic wrap or a piece of cardboard. While keeping the cover in place, invert the jar in a bowl of water.

When the open end of the jar is below the level of the water in the bowl, remove the cardboard, and watch the water come out of the bottle and pour into the bowl until the water is
at the same level in both the jar and the bowl.

Woh! It didn't happen that way! Why not?

Why does the level of the water stay higher in the jar than it does in the bowl?

The weight of the air pressing upon the surface of the water in the bowl is sufficient to support the column of water in the jar.

In other words, the surface of the water in the bowl acts as a lever, onto which the air presses, pushing up on the water in the bottle.