You don't actually need the book from the library - just to have read it. IIRC it is in one of the cabinets to the west of the library itself. Once you have read this and you are on your way out your DK should ask you if you know what you have to do - an impish sort of question at the time.
Hope this helps
marts
BTW not all legs are equal you do NEed a specific spider's leg
