It is a very notable thing that Raffaello, studying the manner of Pietro, imitated it in every respect so closely, that his copies could not be distinguished from his master's originals, and it was not possible to see any clear difference between his works and Pietro's; as is still evident from some figures in a panel in S. Francesco at Perugia, which he executed in oils for Madonna Maddalena degli Oddi. These are a Madonna who has risen into Heaven, with Jesus Christ crowning her, while below, round the sepulchre, are the twelve Apostles, contemplating the Celestial Glory, and at the foot of the panel is a predella divided into three scenes, painted with little figures, of the Madonna receiving the Annunciation from the Angel, of the Magi adoring Christ, and of Christ in the arms of Simeon in the Temple. This work is executed with truly supreme diligence; and one who had not a good knowledge of the two manners, would hold it as certain that it is by the hand of Pietro, whereas it is without a doubt by the hand of Raffaello. After this work, Pietro returning to Florence on some business of his own, Raffaello departed from Perugia and went off with some friends to Citta di Castello, where he painted a panel for S. Agostino in the same manner, and likewise one of a Crucifixion for S. Domenico, which, if his name were not written upon it, no one would believe to be a work by Raffaello, but rather by Pietro. For S. Francesco, also in the same city, he painted a little panel-picture of the Marriage of Our Lady, in which one may recognize the excellence of Raffaello increasing and growing in refinement, and surpassing the manner of Pietro. In this work is a temple drawn in perspective with such loving care, that it is a marvellous thing to see the difficulties that he was for ever seeking out in this branch of his profession. Meanwhile, when he had acquired very great fame by following his master's manner, Pope Pius II[23] had given the commission for painting the library of the Duomo at Siena to Pinturicchio; and he, being a friend of Raffaello, and knowing him to be an excellent draughtsman, brought him to Siena, where Raffaello made for him some of the drawings and cartoons for that work. The reason that he did not continue at it was that some painters in Siena kept extolling with vast praise the cartoon that Leonardo da Vinci had made in the Sala del Papa[24] of a very beautiful group of horsemen, to be painted afterwards in the Hall of the Palace of the Signoria, and likewise some nudes executed by Michelagnolo Buonarroti in competition with Leonardo, and much better; and Raffaello, on account of the love that he always bore to the excellent in art, was seized by such a desire to see them, that, putting aside that work and all thought of his own advantage and comfort, he went off to Florence.