Plate XIII
SPECIMEN OF NIELLO WORK
A ‘Pax’ formerly in the Baptistry, and now in the National Museum, Florence
From this graving by the burin are derived the copper plates from which we see to-day so many impressions throughout all Italy of both Italian and German origin. Just as impressions in clay were taken from silver plaques before they were filled with niello, and casts pulled from these in sulphur,[[285]] in the same manner the printers found out the method of striking off the sheets from the copper plates with the press, as we have seen printing done in our own days.
§ 105. Enamels over Reliefs.
See now another sort of work in silver and in gold, commonly called enamel, a kind of painting intermingled with sculpture, suitable for lining the bottom of pieces intended to hold water.[[286]] This when worked on gold, needs the very finest gold; and when on silver, the silver at least of the quality of the giulio.[[287]] The following method is necessary in order that the enamel may remain in its place and not run beyond its proper limits. The edges of the silver[[288]] must be left so fine that when looked at from above they escape the eye. In this way is made a flat relief contrary to the other kind,[[289]] in order that when the enamels are put over it, it may take its darks and lights from the height and depth of the intaglio. Then glass enamels of various colours are picked out and carefully fixed with the hammer;[[290]] they are kept in little bowls filled with clear water, separated and distinct one from the other. Those which are used with gold are different from those that serve for silver[[291]] and they are worked in the following manner. The enamels are lifted out separately with the most delicate little silver shovel and spread in their places with scrupulous cleanliness, and this is done over and over again, according as the enamel adheres properly, and so with all the quantity that is needed at the time. This done, an earthenware receptacle, made on purpose, is prepared; it must be perforated all over and have a mouthpiece in front, then the muffle, which is a little perforated earthenware cover that will prevent the charcoal falling from above, is introduced into this receptacle, and above the muffle the space is filled up to the top with oak charcoal kindled in the ordinary way. In the empty space which is left under the aforenamed cover the enamelled object is placed on a very thin iron tray to feel the heat gradually and is kept there long enough to admit of the enamels melting, when they flow all over almost like water. Which done, it is allowed to cool, and then with a ‘frassinella,’ that is, a stone for sharpening iron tools, and with sand such as is used for drinking glasses moistened with clear water, it is rubbed till it becomes perfectly level. When the process of removing all superfluity is finished, the object is placed in the actual fire, to be melted a second time in order that the whole surface may become lustrous.[[292]] Another sort is made by hand, and polished with Tripoli plaster (powder) and a piece of leather, but of this there is no need to make mention.[[293]] I have however described the above because being, like the other processes, of the nature of painting it seemed to come into our subject.
CHAPTER XX. (XXXIV.)
Of Tausia,[[294]] that is, work called Damascening.
§ 106. Metal Inlays.
In imitation of the ancients, the moderns have revived a species of inlaying in metals, with sunk designs in gold or silver, making surfaces either flat or in half or low relief; and in that they have made great progress. Thus we have seen works in steel sunk in the manner of tausia, otherwise called damascening, because of its being excellently well done in Damascus and in all the Levant. Wherefore we have before us to-day many bronzes and brasses and coppers inlaid in silver and gold with arabesques, which have come from those countries; and among the works of the ancients we have observed rings of steel, with half figures and leafage very beautiful. In our days, there is made in this kind of work armour for fighting all worked with arabesques inlaid with gold, also stirrups and saddle-bows and iron maces: and now much in vogue are such furnishings of swords, of daggers, of knives and of every weapon that men desire to have richly ornamented. Damascening is done in this way. The worker makes undercut sinkings in the iron[[295]] and beats in the gold by the force of a hammer, having first made cuttings or little teeth like those of a slender file underneath, so that the gold is driven into these hollows and is fixed there.[[296]] Then by means of tools, he enriches it with a pleasing design of leaves or of whatever he fancies. All these designs executed with threads of gold passed through the wire-drawing plate[[297]] are twined over the surface of the iron and beaten in with the hammer, so as to be fixed in the method mentioned above. Let care however be taken that the threads are thicker than the incised outlines so as to fill these up and remain fixed into them. In this craft numberless ingenious men have executed praiseworthy things which have been esteemed marvellous; and for this reason I have not wished to omit mention of it, for it depends on inlaid work and so, partaking of the nature of both sculpture and painting, is part of the operations of the art of design.