In chasteness of design, Raffaello was by some placed on a level with the Greeks, though this praise we must consider as extravagant. Agostino Caracci commends him as a model of symmetry; and in that respect, more than in any other, he approached the ancients; except, observes Mengs, in the hands, which being rarely found perfect in the ancient statues, he had not an equal opportunity of studying, and did not therefore design them so elegantly as the other parts. He selected the beautiful from nature, and as Mariette observes, whose collection was rich in his designs, he copied it with all its imperfections, which he afterwards gradually corrected, as he proceeded with his work. Above all things, he aimed at perfecting the heads, and from a letter addressed to Castiglione on the Galatea of the Palazzo Chigi, or of the Farnesina, he discovers how intent he was to select the best models of nature, and to perfect them in his own mind.[48] His own Fornarina assisted him in this object. Her portrait, by Raffaello's own hand, was formerly in the Barberini palace, and it is repeated in many of his Madonnas, in the picture of S. Cecilia, in Bologna, and in many female heads. Critics have often expressed a wish that these heads had possessed a more dignified character, and in this respect he was, perhaps, excelled by Guido Reni, and however engaging his children may be, those of Titian are still more beautiful. His true empire was in the heads of his men, which are portraits selected with judgment, and depicted with a dignity proportioned to his subject. Vasari calls the air of these heads superhuman, and calls on us to admire the expression of age in the patriarchs, simplicity of life in the apostles, and constancy of faith in the martyrs; and in Christ in the Transfiguration, he says, there is a portion of the divine essence itself transferred to his countenance, and made visible to mortal eyes.