Borgo S. Sepolcro, Foligno, and Perugia, present us with artists of greater celebrity. Borgo was a part of Umbria subject to the Holy See, and was, in 1440, pledged to the Florentines,[13] by Eugenius IV. at the time Piero della Francesca, or Piero Borghese, one of the most memorable painters of this age, was at the summit of his reputation. He must have been born about 1398, since Vasari states that "he painted about the year 1458,"[14] and that he became blind at sixty years of age, and remained so until his death, in his eighty-sixth year. From his fifteenth year he applied himself to painting, at which age he had made himself master of the principles of mathematics, and he rose to great eminence both in art and science.[15] I have not been able to ascertain who was his master, but it is probable that as he was the son of a poor widow, who had barely the means of bringing him up, he did not leave his native place; and that under the guidance of obscure masters he raised himself, by his own genius, to the high degree of fame which he enjoyed. He first appeared, says Vasari, in the court of the elder Guidubaldo Feltro, Duke of Urbino, where he left only some pictures of figures on a small scale, which was the case with such as were not the pupils of the great masters. He was celebrated for a remarkable drawing of a Vase, so ingeniously designed that the front, the back, the sides, the bottom, and the mouth, were all shewn; the whole drawn with the greatest correctness, and the circles gracefully foreshortened. The art of perspective, the principles of which he was, as some affirm, the first among the Italians to develope and to cultivate, was much indebted to him;[16] and painting, too, owed much to his example in imitating the effects of light, in marking correctly the muscles of the naked figure, in preparing models of clay for his figures, and in the study of his drapery, the folds of which he fixed on the model itself, and drew very accurately and minutely. On examining the style of Bramante and his Milanese contemporaries, I have often thought that they derived some light from Piero, for, as I have before said, he painted in Urbino where Bramante studied, and afterwards executed many works in Rome, where Bramantino came and was employed by Nicholas V.