Bartholomew takes off his hat as the king?s carriage passes, but another one mysteriously appears on his head. Outraged at the boy?s impudence, the king takes him to the castle where all of his guards, Wise Men, and magicians fail to prevent new hats from coming out of nowhere. When they eventually add up all of the hats, they discover that there are 500! Dr. Seuss combines a zany tale and an excellent introduction to large numbers.