The British Museum has lately acquired a square plaque of clear thick glass; at the back, in deep intaglio, is the portrait of a Doge, who, on the ground of the letters A. G. on either side of the head, may be identified with Andrea Gritti (1523-1538).[[155]] The late M. Piot has extracted from a fifteenth-century treatise on architecture by Antonio Averlini a dialogue between two artists upon some curious applications of glass. We hear of cristallino plaques with figures carved on the lower surface, so as apparently to stand out in relief—a description which would apply well enough to this piastra.
There is no more troubled story in the history of glass-making than that of the manufacture of Mirrors at Murano from the fourteenth to the eighteenth century. We have seen in the early days, when these mirrors were backed with lead (p. [138]), that the Germans had already become experts in this department. More than once in the Venetian archives there are references to the secret methods of these Todeschi. In a petition of 1503 there is mention of a plan for making good and perfect mirrors, a precious secret unknown except to certain Germans. It is impossible to resist the suspicion that there is here a reference to the cylinder process, which, as we have seen, was already known to Theophilus (p. [129]); by this process it would have been possible to produce a fairly large and comparatively flat sheet of glass. The Venetians, on the other hand, probably continued to a late period to use the old method of ‘spinning’ or ‘flashing.’[[156]]
It was only after the middle of the sixteenth century that the mirror-makers, the specchiai, formed themselves into a separate corporation; but in this guild were included, it would seem, the makers of the so-called mirrors of steel.[[157]] Thus we find that in 1574, one Francesco Zamberlan, who only two years before had taken out a patent for his ‘specchi d’acciaio,’ was admitted to the new guild on the ground of his special knowledge. Those engaged in the polishing—the lustratura and spianatura—of both materials, glass and metal, were also members of the guild.
For us the interest in these mirrors lies rather in the framing. We find the new corporation early engaged in quarrels with the painters and with the workers in tarsia, mother-of-pearl, and coral (i miniatori, i marangoni, e muschieri), who found employment in decorating the frames.
For a time, no doubt, the Venetian mirrors held their own, but before the end of the seventeenth century the French, thanks to the energy of Colbert, had not only learned all their secrets, but by an entirely new method—namely by a process of casting or founding, and subsequent rolling and polishing of the glass plates—were able to meet the demand for the large mirrors that were now regarded as indispensable in a Louis-Quatorze salon. But these ‘glaces de St. Gobain’ are of an entirely different nature from the exquisitely framed little lustri with which we are now concerned. Unfortunately, as far as I know, there are no characteristic specimens of these cinquecento mirrors—at least of those in which glass forms an important element in the frame as well—in any of our public collections. For fine examples of such work we must go to the Louvre or the Hôtel de Cluny. It will be noticed that the margin of the glass is invariably bevelled, thus forming a transition to the elaborate framing. These cinquecento Italian mirrors were extensively copied, and this at an early date, both in France and at Nuremberg.
In spite of the heroic efforts made by the authorities in the late seventeenth and in the following century to introduce the new methods of working glass at Murano, the Venetians failed to maintain their position. It was only in the more conservative Eastern markets that the demand for their mirrors was kept up; even to-day, in Syria or in Persia, these Italian glasses may not unfrequently be seen in private houses and even in mosques.
Another characteristic application of the glass of Murano was to the elaborate chandeliers that formed so important a part in the decoration of the reception-rooms of a Venetian palace in the seventeenth century. In these the metal framework is completely hidden by a thick foliage, as it were, of glass—frequently of the opalescent calcedonio—amid which the tall wax candles spring up here and there. M. Gerspach extols the decorative value of these chandeliers:—‘Le soir, le lustre de Venise allumé est un rayonnement harmonieux sans reflets discordants; le jour, stalactite ciselée, il égaye l’appartement comme une note claire et joyeuse’ (La Verrerie, p. 173).
In the eighteenth century the contorted forms, imitating leaves and flowers, were replaced by pendent discs of colourless crystal, cut, polished, and often facetted. Of these later chandeliers there is a splendid series, whether of Venetian origin or not I do not know, at Hertford House. Such chandeliers were known in England in the eighteenth century as ‘lustres.’[[158]] They are above all numerous in German palaces, and most of the glass is probably of German or Flemish origin. But of the earlier type I cannot find a single example in any of our public museums.[[159]] The manufacture, however, has been revived at Murano, and chandeliers of this class, with no claims to antiquity, may often be seen in private houses both at home and abroad. The spread of electric lighting has given a stimulus to work of this kind, for the corolla-shaped shades that so often accompany our incandescent lamps have, in most cases, obviously been modelled upon the glass of the old Venetian chandeliers.
The glass-workers of Murano were a conservative body; their work was based upon secret processes and rule-of-thumb formulas. The elaborate division into different arti or corporations, each governed by its separate mariegola, made it excessively difficult to introduce any radical changes into the methods of work. It is quite pathetic to observe the efforts of the comparatively enlightened governing body, the conservatori alle arti, who in the last years of the republic attempted to introduce the new processes that were revolutionising the glass industry in the north of Europe. We find reports signed by great names—Morosini and others—recommending the introduction of English machinery, and drawing up plans for the cultivation of the Salsola soda on the islands of the lagoons. Little attention apparently was given to the artistic side by these reformers. One of the last names in the long list of the Murano glass-makers is that of Giuseppe Briati, famous for the purity of his cristallo; he excelled, too, in the designing and the execution of the vetro di trina, and Lazari declares that much of the ‘lace glass’ in our collections attributed to the cinquecento belongs rather to him or to his school.[[160]] Briati in 1739 was allowed to set up a furnace in Venice itself for the preparation of his cristallo, the first time for more than four hundred years that such a permission had been granted. It is of this Briati that we are told that his glass found a place on the credenza or buffet at the public banquets of the Doge, beside the gold and silver plate. This would appear to have been an innovation (see above, p. [203]) introduced with the special aim of encouraging the declining industry. An exception was again made in favour of one Giorgio Barbaria, who so late as 1790, in the parish of the Gesuiti, manufactured bottles by a new English method. But as a French writer somewhat naïvely puts it—‘ce genre ne prête guère à la fantaisie.’
Before this time the Venetians had yielded to the new fashion of the day, and were making cut and engraved glass more or less after German or Bohemian models. Of this class were the trionfi di tavola—trophies of glass for the decoration of the dinner-table—as well as the gigantic chandeliers known as ‘ciocche.’ To such productions the artistic work of the time appears to have been confined. Of the first there is a fine specimen from the Casa Morosini set out in the centre of one of the rooms in the Museo Civico at Venice. I have already mentioned the chandeliers of cut glass. They played an important part in a rococo interior.