In regard to the province of colour, Raffaello must yield the palm to Titian and Correggio, although he himself excelled Michelangiolo and many others. His frescos may rank with the first works of other schools in that line: not so his pictures in oil. In the latter he availed himself of the sketches of Giulio, which were composed with a degree of hardness and timidity; and though finished by Raffaello, they have frequently lost the lustre of his last touch. This defect was not immediately apparent, and if Raffaello's life had been prolonged, he would have been aware of the injuries his pictures received from the lapse of time, and would not have finished them in so light a manner. He is on this account more admired in his first subject in the Vatican, painted under Julius II., than in those he executed under Leo X., for being there pressed by a multiplicity of business, and an idea of the importance of a grander style, he became less rich and firm in his colouring. That, however, he excelled in these respects is evinced by his portraits, when not having an opportunity of displaying his invention, composition, and beautiful style of design, he appears ambitious to distinguish himself by his colouring. In this respect his two portraits of Julius II. are truly admirable, the Medicean and the Corsinian: that of Leo X. between the two cardinals; and above all, in the opinion of an eminent judge, Renfesthein, that of Bindo Altoviti, in the possession of his noble descendants at Florence, by many regarded as a portrait of Raphael himself.[50] The heads in his Transfiguration are esteemed the most perfect he ever painted, and Mengs extols the colouring of them as eminently beautiful. If there be any exception, it is in the complexion of the principal female, of a greyish tint, as is often the case in his delicate figures; in which he is therefore considered to excel less than in the heads of his men. Mengs has made many exceptions to the chiaroscuro of Raffaello, as compared with that of Correggio, on which connoisseurs will form their own decision. We are told that he disposed it with the aid of models of wax; and the relief of his pictures, and the beautiful effect in his Heliodorus, and in the Transfiguration, are ascribed to this mode of practice. To his perspective, too, he was most attentive. De Piles found, in some of his sketches, the scale of proportion.[51] It is affirmed by Algarotti, that he did not attempt to paint _di sotto in su_. But to this opinion we may oppose the example we find in the third arch of the gallery of the Vatican, where there is a perspective of small columns, says Taja, imitated _di sotto in su_. It is true, that in his larger works he avoided it; and in order to preserve the appearance of nature, he represented his pictures as painted on a tapestry, attached by means of a running knot to the entablature of the room.