But plates of glass, somewhat similarly decorated, may play an even more important part in the decoration of the backs of altars, especially on the spandrels in the lower arcades of the reredos. The decoration now becomes pictorial, and is often most carefully executed. Or, again, such a little glass picture may be detached and mounted in a frame to form a pax or baiser-de-paix, a bijou reliquary, or other small devotional object. In such cases the gold is applied to the back of the glass by weak gum, and the design traced with a pointed instrument somewhat in the manner of the catacomb glasses. The effect may be heightened in various ways by additional touches of pigment on the draperies, or by a glazing of colour for the flesh-tints; the colours are worked up with a resinous body, and silver foil in little plates and spangles is added in places; finally, over the back is laid a piece of tinfoil, and this is folded over the edges (M. Alfred André, quoted by M. Molinier, Spitzer Catalogue, vol. iii. p. 54). The back of the plate is generally found to be protected by a kind of pitchy varnish; to fix this some application of heat was doubtless necessary, but in no case, I think, is the gold design in this late mediæval work enclosed between pieces of glass which have been subsequently fused together.[[103]]

We are here concerned only with the Gothic examples of this class of work, and of these the majority appear to come from the north of Italy—they are probably of Milanese or Venetian origin. There is often in these early Italian plaques a coloured backing under the gold, generally of a bright red, but sometimes of green or black, and this backing shows through in places. In the case of a very beautiful example formerly in the Spitzer collection, the design was drawn upon the central portion of a plate of flashed glass; although this medallion is only 51⁄2 inches in diameter, there is a distinct boss in the centre. That such a defective piece should have been chosen for this delicate work would go to prove the rarity of sheets of glass with even surface at this time.

In later days more colour was used in the decoration, but such work as the magnificent baiser-de-paix in the Louvre, which came from the chapel of the order of the St. Esprit, does not fall within our present limit of time.

The late Marquis Emanuele D’Azeglio devoted himself to collecting specimens of gilt and painted glass of all ages and countries. This collection, unique of its kind, he bequeathed to his native town of Turin, where it is now exhibited in the Museo Civico. In some of the earlier pieces, especially on one of Byzantine character—perhaps Muranese work of the end of the thirteenth century—the gold is laid down upon glass of very irregular thickness. There are a few examples of Gothic work of this character in the British Museum, at South Kensington, and in the collection of Mr. Salting.

CHAPTER IX
THE ENAMELLED GLASS OF THE SARACENS

I have here to deal with a singularly restricted family of glass—that made in the Saracenic East during the thirteenth, fourteenth, and fifteenth centuries. This enamelled glass is important for more than one reason. It is undoubtedly, as a group, the most magnificent and decorative that we meet with in the whole course of our history. Technically, again, the interest of the group is supreme, for this application of solid enamels, translucent or transparent, to the surface of glass, was a new departure, and it preceded, as far as we know, the use of any material of the kind in the decoration of porcelain and fayence. The Romans and the Byzantine Greeks, it is true, decorated their glass at times with thin washes of opaque paints, but we have no definite proof that they ever applied fusible lead enamels in this way.

There is every reason to believe that this method of decoration was not in any general use in the East before the thirteenth century. But if we are still quite in the dark as to the origin of the art, it may be some consolation to remember that barely thirty years ago the few rare pieces of Saracenic glass that had reached us were classed as Venetian. It is only quite lately that this important ware has met with due recognition.

No doubt much of the sculptured and engraved glass, that we have for convenience of arrangement dwelt upon in the last chapter, is of Saracenic origin; I do not, however, remember any instance of an Arabic inscription being found on such vessels, but on the deeply carved vases of rock crystal that seem to have formed the models that these engraved glasses closely followed, in more than one case tall cufic characters form part of the decoration. I will only point to the magnificent crystal vase which bears the name of an early Fatimi caliph (975-996 A.D.), preserved in the treasury of St. Mark’s.

Apart from that in daily use among the people, we may, however, look upon the glass made during the first four or five centuries of Arab domination as on the whole following in the wake of the carvings in hard stone, above all in rock crystal, then so much in vogue. During the whole of this period the Saracens had hardly developed any well characterised art of their own: they followed in this, as in so many other matters, the traditions of the countries in which they dwelt. At this period their art was at best but a mingling of Byzantine and Sassanian elements. But before the end of the twelfth century a great change had come about, and during the course of the next century there had arisen a definite style—one that has remained ever since the type of what we know as Saracenic art. It would be impossible to dissociate this change from that which took place in the West about the same time. But the Gothic art that sprung up in the land of the Franks was but one phase of a continuous evolution, while the wonderful outburst that had in the main its centre in Cairo, became either locally stereotyped or shared the decay and neglect that overtook other branches of Mussulman civilisation.