A nursery school driver was delivering a van full of kids home one day when a fire truck zoomed past. Sitting in the front seat of the truck was a Dalmatian dog. The children started discussing the dog’s duties.

"They use him to keep crowds back," said Tommy.

"No," said Billy, "he’s just for good luck."

Peter brought the argument to a close. "They use the dogs," he said firmly, "to find the fire hydrants."