The study beyond was a good deal larger than the one at Malfoy Manor too, though its shelves looked about as tightly crammed. Evidently the new Headmaster had already taken some of the advantages of his new position, and expanded on his private library. Most of the top shelves up by the ceiling were sealed off behind heavy grilles of cold iron, and the volumes behind that protection growled and muttered and occasionally flung themselves at their bars or rattled their chains. It looked as though most of the new acquisitions had the sort of disposition Hagrid would've described as "frisky", or maybe even "feisty".
After a short while, Snape strode into the room. "Stay well clear of that bookcase, and that one, and don't even think about touching any of the uppermost shelves. I really don't want to have to explain your masticated body to your father."