Page:Vasari - Lives of the Most Excellent Painters, Sculptors, and Architects, volume 1.djvu/354

340 required, namely, to find some method by which the work produced in that material should be rendered durable, he considered and cogitated with so much good will on this subject, that he finally discovered the means of defending such productions from the injuries of time. And the matter was on this wise: after having made experiments innumerable, Luca found that if he covered his figures with a coating of glaze, formed from the mixture of tin, litharge, antimony, and other minerals and mixtures, carefully prepared by the action of fire, in a furnace made for the purpose, the desired effect was produced to perfection, and that an almost endless durability might thus be secured to works in clay. For this process, then, Luca, as being its inventor, received the highest praise; and, indeed, all future ages will be indebted to him for the same.

The master having thus, as we have seen, accomplished all that he desired, resolved that his first works in this kind should be those which are in the arch over the bronze door which he had made beneath the organ, for the sacristy of Santa Maria del Fiore, wherein he accordingly placed a, so beautiful for that time, that, when fixed up, it was admired by every one who beheld it, as a truly rare production. Moved by this success, the superintendents resolved that the arch above the door of the opposite sacristy, where Donatello had executed the decorations of the other organ, should be filled by Luca della Robbia with similar figures and works in terra-cotta; whereupon, the artist executed an, which is an extremely beautiful work.