There is one at Liège on which the names of the bishops of Tongres are written, and there is another similar one at Novara. It is probable that the liking for ivory carvings on books arose from the lead given by the ivory diptychs. Indeed in several instances the sides of ivory diptychs are actually inlaid in late bindings of MSS.
WORKS TO CONSULT.
Aglio, A.—Antiquities of Mexico. London, 1830-48. (Vol. 4, at end.) (Quipus.)
Berger.—Histoire de l’ecriture dans l’antiquité. Paris, 1891.
Gori, A. F.—Thesaurus reterum diptychorum consularium et ecclesiasticorum. Florentiae, 1759.
Harland, J.—The Reliquary, Jan., 1865. (Clog almanacks.)
Labarte, J.—Histoire des Arts Industrielles au moyen age. (Diptychs.) Paris, 1864-66.
Lacroix, P.—Les arts au moyen age. (Diptychs.) Paris, 1809.
Lubbock, Sir J.—Prehistoric Times. London, 1865.
Madan, F.—Books in Manuscript. London, 1893.