Following the rule that the forms of binding have always followed tolerably closely the forms of the manuscript they have covered, we find that rolls were kept in cylindrical boxes, called “scrinia.” Each roll was usually provided with a little tag, so that if there were several of them in one box they could easily be distinguished. The same sort of tags are used to-day in the case of rolled maps kept on shelves. Until a late period the term parchment must be understood to mean vellum. Now we call sheep skin “parchment” and calf skin “vellum,” and they are prepared in the same way with lime, so that not being tanned they are not strictly “leather.” The finest vellum is prepared from the very youngest and smallest calves, and it is the most beautiful and suitable material for writing or printing upon that has ever yet been found. The surface is singularly even and offers little or no resistance to a pen, so that every sort of handwriting, square or round, is put upon it with equal ease. Vellum has one fault alone, particularly when bound in book form as distinct from a roll, and this is that the edges are apt to cockle, and by so doing they not only make the pages look ugly, but they also admit the dust. Often and often magnificent vellum books, especially at the top, show large vandykes of dust-stained spaces due to this cockling, and all such books should be provided with a close fitting cardboard cap, to be kept upon them whenever they are not in use. Parchment and vellum were both well-known to the ancients, but their value as materials for writing upon does not seem to have been fully acknowledged until the second century B.C., until which period papyrus had held undisputed pre-eminence for that purpose. At that time for some reason the supply of papyrus from Egypt ran short, and Eumenes II., King of Pergamum, successfully introduced parchment in its stead. Parchment is so called because it was first produced at Pergamum.