Early liturgical books reflect the ecclesiastical art of their time—This feature a continuous characteristic of illumination down to the latest times—Elements of Celtic ornament—Gospels of St. Chad—Durham Gospels—Contrast of Celtic and Byzantine—St. Columba—Book of Kells—Details of its decoration.

In the earlier centuries of Christianity, when liturgical books were the chief occupation of the illuminator, it will need little pointing out to demonstrate that the page of the illuminated manuscript, where it contained more than the mere ornamental initial, was simply a mirror of the architectural decoration of the church in which it was intended to be used. Where the church enrichments consist, as on the Byzantine basilicas, of panellings, arcades, and tympana of gilded sculpture in wood or stone, with figures of saints, the pages of the Gospel-book bear similar designs. Where, as in the Romanesque, they are rich in mosaics, and fretted arcades interlacing each other, so are the illuminated Lives of the Saints, the Menologia, Psalters, and Gospel-books. Where, as in the Gothic cathedrals of the West—of France, Germany, or Italy—the stained glass is the striking feature of the interior, so it is with the illumination; it is a “vitrail”—a glass-painting on vellum. On this latter point we shall have more to say when we reach the period of Gothic illumination.

Incidentally, also, the book reflects the minor arts in vogue at the period of its execution. Often in the illumination we may detect these popular local industries. We see mosaic enamelling, wood- and stone-carving, and lacquer-work, and as we approach the Renaissance, even gem-cutting and the delicate craft of the medallist. In Venice and the Netherlands we have the local taste for flower-culture; in Germany we find sculpture in wood and stone; in France the productions of the enameller and the goldsmith; until at length, in the full blaze of the Renaissance itself, we have in almost every land the same varieties of enrichment practised according to its own special style of work.

It has been said that the oldest Celtic illuminated MSS. show no signs of classic, or even Byzantine, influence, yet the plan or framework of the designs makes use both of the cross and the arch, as used in the earliest Byzantine examples. The details, indeed, are quite different, and manifestly derived from indigenous sources. It may be, therefore, that the framework is merely a geometrical coincidence which could not well be avoided. The fact that the basis of pure Irish ornament is geometrical, and developed out of the prehistoric and barbarous art of the savages who preceded the Celts in Ireland; such art as is used on the carved shafts of spears, and oars, and staves of honour, and afterwards on stone crosses and metal-work, may account for the similarity of ideas in ornament developed by old Roman decorators in their mosaic pavements, and may reconcile, in some measure, the varied opinions of different writers who have approached the subject from different points of view. Westwood adhered to the theory of its being purely indigenous. Fleury, on the other hand, in his Catalogue of the MSS. in the Library at Laon, asserts that we owe the knots and interlacements to the influence of the painters, sculptors, and mosaicists of Rome. “These interlacings, cables, etc., there is no Gallo-Roman monument which does not exhibit them, and, only to cite local instances, the cord of four or five strands is seen in the beautiful mosaics discovered in profusion within the last five years (1857-62) at Blanzy, at Bazoches, at Vailly, and at Reims. It was from them that the Franks borrowed their knots and twists and ribbons for their belts and buckles, their rings and bracelets” (pt. i., p. 8).

The elements, therefore, of book ornament, as used by the Celtic penmen, are such as were employed by the prehistoric and sporadic nations in the textile art in plaiting and handweaving, and afterwards transferred to that of metal-work. Terminals of animal, bird, or serpent form afterwards combine with the linear designs. The dog and dragon are common, as may be seen in the archaic vases produced by the Greeks before they came under the influence of ideas from Western Asia.

Among Celtic artists, as among those of later times, the practice of working in various materials was common to the same individual, and Dagæus (d. 586) may compare with Dunstan, Eloy, Tuotilo, and others.