Ron gulped. "He, um," he stammered, "he said you need music ..." It sounded patently ridiculous, that suggestion, in the face of the snarling dog itself, but that was what Hagrid had said; and judging by the door-left-ajar and the absence of any other presence in the room, Snape or Quirrell or whoever (there was some general disagreement on this point) had gone down the trapdoor.