Flourish and Blotts stocks a wide range of books that are stacked from floor to ceiling: some leather-bound and as big as paving stones, some tiny and covered in silk, and some that have to be kept in a cage to stop them attacking passersby. They regretted their purchase of 200 copies of the Invisible Book of Invisibility when they couldn't find them and had to take the loss on the whole lot. They equally regretted stocking the Monster Book of Monsters
