"I AM NOT PAYING FOR SOME CRACKPOT OLD FOOL TO TEACH HIM MAGIC TRICKS!" yelled Uncle Vernon.
But he had finally gone too far. Hagrid seized his umbrella and whirled it over his head, "NEVER," he thundered, "- INSULT- ALBUS- DUMBLEDOREIN- FRONT- OF- ME!"
He brought the umbrella swishing down through the air to point at Dudley -- there was a flash of violet light, a sound like a firecracker, a sharp squeal, and the next second, Dudley was dancing on the spot with his hands clasped over his fat bottom, howling in pain. When he turned his back on them, Harry saw a curly pig's tail poking through a hole in his trousers.

Harry Potter and the Philosopher's Stone - Chapter 4 : The Keeper of the Keys
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