From jacket flap:
This is a picture book, with descriptions, of rare and valuable books which are remarkable for their beauty either inside or outside. The finest books existing are to be found among the Illuminated Manuscripts of the Middle Ages, but the decoration of the outsides of fine books from Byzantine times to the present is also often worthy of sympathetic admiration. The Monasteries of olden days had special workshops, connected with the Scriptoria, in which due clothing of rare manuscripts in jewelled and enamelled gold, silver, or copper, was skillfully carried out. And in later times distinguished artists in Italy, France and England brought the beautiful art of gold tooling on leather to its highest point of perfection.