A boy was riding along the street 
in a home-made cart pulled by a dog
with a rope attached to the dog's 
genitals. On the side of the cart the
boy had written "Police."

A passer-by watched with interest. 
When the cart stopped, he told the
boy, "You know, your police car 
would go a lot faster if you tied the 
rope around your dog's neck."

"I know," said the boy, "but I wouldn't 
get the cool siren."