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156 brass in the centre, with smaller bosses or buttons upon the corners, was also used to protect the gilding from abrasion. On the cheaper books, bound in hog-skin, iron corners and a closely set studding of round-headed iron nails were used for the same purpose. To prevent the covers from warping outward, two clasps of brass were attached to the covers.

The book thus bound was too weighty to be held in the hand; it was so full of angles and knobs that it could not be placed upon a flat table without danger of scratching it. For the safety of the book and the convenience of the reader, it was necessary that the book should be laid on an inclined desk or a revolving lecturn, provided with a ledge for holding it up and with holdfasts for keeping down the leaves. The lecturn was really required for the protection of the reader. Petrarch, when reading an unwieldy volume of the Epistles of Cicero, which he held in his hands, and in which he was