the Pope Sixtus IV., together with Signorelli and Botticelli, to cover the walls of the Sixtine Chapel with frescoes. Of the four allotted to Perugino (which occupied him in part for six years) three were afterwards destroyed to make room for Michael Angelo's "Last Judgment"; the fourth, the "Delivery of the Keys to St. Peter," remains. Perugino's subsequent movements are not easy to follow,[134] and we can only here allude to some of his most famous works. In 1494 he was at Venice, and in the same year painted his very beautiful altar-piece in S. Agostino at Cremona. In 1495 he contracted to paint for the monks of Cassino the noble Assumption now at Lyons. In 1496 he painted for the Cathedral of Perugia, the famous "Sposalizio," now at Caen. To the same period in his career belongs the picture now before us, painted for the Certosa of Pavia. Down to about 1493, Perugino's easel pictures were executed in _tempera_ (see 181); he then adopted the new oil medium, which he used to such splendid effect in richness of colour. In 1499 he was at Perugia, engaged upon the beautiful frescoes in the Hall of the Bankers (Collegio del Cambio). He was afterwards in Florence, but in 1505 returned to Perugia, where in 1507 he painted the altar-piece, No. 1075 in our gallery. In his later years he erected a large studio in which several scholars were employed to execute commissions from his designs, and the works of this period show considerable inequality of execution, as well as repetition of design, and some falling off in richness of colouring. According to Vasari's gossip Perugino was very careful of his money--as one who had seen such hard times might well be; would only paint for cash down, and on all his wanderings carried his money box with him. "When it is fair weather," he used to say, "a man must build his house, that he may be under shelter when he most needs it." It was not, however, till middle life that he did literally build himself a house. At the same time he married a very beautiful girl, and is said to have had so much pleasure in seeing her wear becoming head-dresses that he would spend hours together in arranging that part of her toilet with his own hands. There is a tradition that she was the model for the angel who accompanies Tobias in our picture. The master was still painting in his 77th year, and was engaged on a fresco at Frontignano (now in this gallery, No. 1441), when he was carried off by the plague. The most famous of his pupils was Raphael; among the rest, the most accomplished were Giovanni lo Spagna (1032), and Giannicola Manni (1194).