There was a thud of metal as Ginny’s cauldron went flying; Mr. Weasley had thrown himself at Mr. Malfoy, knocking him backward into a bookshelf. Dozens of heavy spellbooks came thundering down on all their heads; there was a yell of, “Get him, Dad!” from Fred or George; Mrs. Weasley was shrieking, “No, Arthur, no!”; the crowd stampeded backward, knocking more shelves over; “Gentlemen, please — please!” cried the assistant, and then, louder than all —
“Break it up, there, gents, break it up —”
Hagrid was wading toward them through the sea of books. In an instant he had pulled Mr. Weasley and Mr. Malfoy apart. Mr. Weasley had a cut lip and Mr. Malfoy had been hit in the eye by an Encyclopedia of Toadstools.

Harry Potter and the Chamber of Secrets - Chapter 4 : At Flourish and Blotts
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