The Italians certainly succeeded in performing feats of lapidary art at a later period. Vasari mentions two cups ordered by Duke Cosmo, one cut out of a piece of lapis lazuli, and the other from an enormous heliotrope, and a crystal galley with gold rigging was made by the Sanachi brothers. In the Green Vaults in Dresden may be seen numerous specimens of valuable but hideous products of this class. In the seventeenth century, the art had run its course, and gave place to a taste for cameos, which in its turn was run into the ground. Cameo-cutting and gem engraving has always been accomplished partly by means of a drill; the deepest point to be reached in the cutting would be punctured first, and then the surfaces cut, chipped, and ground away until the desired level was attained. This is on much the same principle as that adopted by marble cutters to-day. Mr. Cyril Davenport's definition of a cameo is quite satisfactory: "A small sculpture executed in low relief upon some substance precious either for its beauty, rarity, or hardness." Cameos are usually cut in onyx, the different layers and stratifications of colour being cut away at different depths, so that the sculpture appears to be rendered in one colour on another, and sometimes three or four layers are recognized, so that a shaded effect is obtained. Certain pearly shells are sometimes used for cameo cutting; these were popular in Italy in the fifteenth century. In Greece and Rome the art of cameo cutting was brought to astonishing perfection, the sardonyx being frequently used, and often cut in five different coloured layers. An enormous antique cameo, measuring over nine inches across, may be seen in Vienna; it represents the Apotheosis of Augustus, and the scene is cut in two rows of spirited figures. It dates from the first century A. D. It is in dark brown and white. Among the treasures of the art-loving Henry III. was a "great cameo," in a golden case; it was worth two hundred pounds. This cameo was supposed to compete with a celebrated work at Ste. Chapelle in Paris, which had been brought by Emperor Baldwin II. from Constantinople. [Illustration: SARDONYX CUP, 11TH CENTURY, VENICE] In Paris was a flourishing guild, the "Lapidaries, Jewel Cutters, and Engravers of Cameos and Hard Stones," in the thirteenth century; glass cutters were included in this body for a time, but after 1584 the revised laws did not permit of any imitative work, so glass cutters were no longer allowed to join the society. The French work was rather coarse compared with the classic examples.