surgeon at Pompeii. One of the staves, with the papyrus rolled round it, was held in each hand, at a distance apart equal to the width of one or more of the transverse columns of writing. As soon as the eye was carried down to the bottom of a column, one hand rolled up and the other unrolled sufficient of the papyrus to bring a fresh column opposite to the reader's eye, and so on until the whole was wound round one of the staves, when, of course, the student had arrived at the end of his book. Eumenes, king of Pergamus, being unable to procure the Egyptian papyrus, through the jealousy of one of the Ptolemies, who occupied himself in forming a rival library to the one which subsequently became so celebrated at Pergamus, introduced the use of parchment properly "dressed" for taking ink and pigments; and hence the derivation of the word "pergamena" as applied to parchment or vellum; the former substance being the prepared skin of sheep, and the latter of calves.[1] The sheets of parchment were joined end to end, as the sheets of papyrus had been, and when written upon, on one side only, and in narrow columns across the breadth of the scroll, were rolled up round staves and bound with strings, to which seals of wax were occasionally attached, in place of the more common leaden bullæ. The custom of dividing books into pages is said by Suetonius to have been introduced by Julius Cæsar, whose letters to the Senate were so made up, and after whose time the practice became usual for all documents either addressed to, or issuing from, that body, or the emperors. As that form subsequently crept into general use, the books were known as "codices;" and hence the ordinary term as applied to manuscript volumes. All classes of books, the reeds for writing in them, the inkstands, and the "capsæ" or "scrinia," the boxes in which the "scapi" or rolls were kept, are minutely portrayed in ancient wall-paintings and ivory diptychs. The inkstands are generally shown as double, no doubt for containing both black and red ink, with the latter of which certain portions of the text were written.[2]