A professor of chemistry wanted to teach his fifth-grade class a lesson about the evils of liquor, so he produced an experiment that involved a glass of water, a glass of whiskey, and two worms.

"Now, class. Observe worms closely," said the professor, putting a worm first into the water. The worm in the water writhed about, happy as a worm in water could be.

He put the second worm into the whiskey. It writhed painfully and quickly sank to the bottom, dead as a doornail.

"Now, what lesson can we derive from this experiment?" the professor asked.

Johnny, who sits in the back of the room, raised his hand and responded, "Drink whiskey and you won't get worms."