Two men went up in a hot-air balloon one May morning. Suddenly they were enveloped by clouds and lost track of where they were. They drifted for what seemed like hours. Finally the cloud parted, and they spotted a man below them on the ground.

"Where are we?" one of the passengers hollered down. The man on the ground looked around, looked up at the balloon, looked around some more and then yelled back, "You're in a balloon."

The two balloonists looked at one another and then one of …