Since mention has been made more than once of reading and libraries, it is well to realise the form commonly taken by books.  We must not think of the modern bound volume standing on its shelf or open in the hand.  At our date any books made up in the form of leaves—­or what the Romans called “tablet” form—­consisted only of some four or six pages.  The regular shape for a book was that of a roll, or, if the work was a large one, it might consist of several such “rolls” or “sections.”  The material was either paper—­in its original sense of papyrus—­or the skin known as parchment.  Papyrus was naturally the cheaper and the less durable.  Prepared sheets of a given length and breadth—­the “pages”—­were written upon and then pasted to each other side by side until a long stretch was formed.  The last sheet was then attached to a thin roller, commonly of wood, answering to that used in a modern wall-map.  Round a roll of any pretensions there was wrapped a cover of coloured parchment, red, yellow, or purple.  The ends of the roll were rubbed smooth with pumice-stone and dyed, and a tag or label was affixed to bear the name of the author and the work.  A number of such rolls, related in subject or authorship, were placed on end in a round box, with the labels upwards ready for inspection.  In the library such a box would stand in a pigeon-hole or section of shelf, from which it might be carried where required.  Sometimes the rolls themselves lay in a heap horizontally in a pigeon-hole without a box, but this manifestly a less convenient practice.  To keep the bookworms cedar-oil was rubbed upon them, giving them a yellowish tinge.  The reader, taking the body of the roll in one hand, begins to unwind the long strip with the other.  After reading the first column or page thus exposed, he mechanically re-winds that portion, while the width of another page is pulled into view.  The writing itself was done by means of a reed, sharpened and split like a quill-pen, and dipped in ink made in various ways, but mostly less “biting” than our own.  This made it comparatively easy to sponge out what was written, and to use the same roll over again—­as a “palimpsest”—­for some work more desired.  It is perhaps needless to say that the writing was regularly to be found upon one side only.  If the back was used, it was for economy, for unimportant notes, or as an exercise book for schoolboys.  We may imagine a fine library copy, or edition de luxe, of Virgil as consisting of a number of rolls, each a long strip of the best parchment rolled round a staff of ivory with gilded ends.  Its “cover” is a wrapper of parchment richly dyed and bearing coloured bands of leather to serve as fasteners.  From the smoothed and dyed end stands out a scarlet label, marked “Virgil Aeneid Book I.” (or as the case may be).  When opened, the first page will reveal a painted portrait of the poet, and the writing will be found to be in a beautifully clear and even calligraphy.  Beside the shelf on which the work is placed there likely stands a lifelike bust of Virgil in marble in bronze.