I shall now give some account of the chiaroscuros executed in mosaic, which owe their perfection to the school of Siena, during the epoch of which we are about to finish our account. I have already mentioned the erection of the magnificent cathedral of Siena, a work of many years; and may now add, that though it was grand in all its parts, nothing shewed such originality, or was so generally admired as the pavement around the great altar, all storied with subjects taken from the New Testament, of which the figures were surrounded by appropriate ornaments, which served to vary and divide the immense ground of the painting. A succession of artists always labouring to improve this work, carried it in a few years to an astonishing pitch of excellence. The nature of the stone quarries in the Sienese territory, afforded also facilities to the art which could not be so easily attained in other places. It originated like other arts from small and rude beginnings. Duccio commenced this ornamented pavement. The part which he executed is constructed of stones, in which the limbs and contours of the figures are scooped out: it is a dry but not ungraceful production of the thirteenth century. The young woman in the choir who kneels with her arms leaning on a cross, and, as an inscription informs us, implores the mercy of the Lord, is the work of Duccio: it probably represents Christian piety; and certainly both the attitude and the countenance are expressive of what she asks. Those who continued the pavement immediately after Duccio, are not so well known. We read of an Urbano da Cortona, and an Antonio Federighi, who designed and executed the two Sybils; the rest was in like manner the work of artists of little note. They all, however, improved the art in some degree, cutting the figures with the chisel, and filling up what was removed by the iron, with pitch or some black composition; and this was a rude sort of chiaroscuro. To them succeeded Matteo di Giovanni, who, from an attentive consideration of what his predecessors had done, fell on a method of surpassing them. He remarked a vein of the marble in the drapery of a figure of David, which formed a very natural fold, and by the contrast of the colours made the knee and leg appear in relief: in like manner he discovered in a figure of Solomon a shade of colour in the marble, well suited to produce effect. He then selected marbles of different colours; and joining them after the manner of an inlaying with stained wood, produced a work that was entitled to the name of a marble chiaroscuro. In this manner he executed without assistance a Slaughter of the Innocents, a composition which he frequently repeated, as we before remarked. He thus opened the path for Beccafumi's histories, who wrought in a superior style a large part of that pavement, which his exertions, says Vasari, rendered "the most beautiful, the largest, and most magnificent that was