A nursery school teacher was delivering a station wagon 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 one child.
'No,' said another, 'he's just for good luck.'
A third child brought the argument to a close. 'They use the dogs,' she said firmly, 'to find the fire hydrants.