[115] These pictures, like the other Florentine works here exhibited, except 564 (which is on linen cloth attached to wood) and 276 (which is in fresco), are painted in tempera on wood. Tempera (or distemper) painting is a generic term for the various methods in which some other substance than oil was the medium. Various substances were thus used—such as gum, glue or size, flour-paste, white of egg, milk of figs. Cennino Cennini, who wrote a treatise on painting at the end of the fourteenth century, professes to give the exact method of Giotto. Egg beaten up with water was preferred by him, except where the yellowness of the mixture injured the purity of the colour. The colours thus mixed were laid on to a panel (or on to a cloth stretched over the panel) previously prepared with a smooth white ground of plaster. And finally oil or albumen was used to go over the whole surface. This was the practice in general use for all detached pictures until the middle of the fifteenth century, when what is known as "the Van Eyck method" came into vogue (see under 186).
Fresco painting is painting upon walls of wet plaster with earths of different colours diluted with water. It is so called from the colour being applied to the fresh wet surface of lime, but it is of two kinds: (1) fresco secco, when the plaster of lime has been allowed to dry on the wall and is then saturated with water before painting; this was the method in use till after Giotto's time; (2) buon fresco, when the colours are laid on to the fresh plaster before it is yet dry. (The fullest account of these various technical processes and their history is Sir C. Eastlake's "Materials for a History of Oil Painting," a review of which by Ruskin appeared in the Quarterly Review, and is reprinted in On the Old Road, vol. i.).
[116] The note in the Official Catalogue says that the picture does not correspond in the scheme of colour to the works of Velazquez's early period. On the other hand, "it shows so decided an affinity with the fine picture by Zurbaran, in the Palace of San Telmo, at Seville, not only in colouring but in every detail of the treatment, that there can be no doubt that the attribution to Velazquez was an error, and that Zurbaran is the true painter of this beautiful work, which may be considered the best picture he ever painted." But "we would fain see proof," says another critic, "that Zurbaran ever painted a head like that of the Divine Child. The rest of the picture recalls the early Seville manner of Velazquez in the style of Ribera" (Quarterly Review, April 1899).
[117] This picture, when first purchased for the National Gallery in 1853, was ascribed to Giorgione. For many years it was given to the "School of Bellini." In 1883 it was identified by Messrs. Crowe and Cavalcaselle as a work by Catena. Signor Morelli and other critics of his school supported this view, which in 1898 was adopted by the authorities of the Gallery. No. 694 has also been so attributed to him in the Catalogue. Other pictures which have at one time or another been connected with Catena are 599, 812, and 1160.
[118] "The roguish little terrier pretends not to see what is going on. But what are the partridges doing behind the chair of the Blessed Virgin? Was the Knight a worldling, given to sport, but arrested in the pursuit of pleasure by some inward voice or vision; and so, taking the result of the day's work, he lays it at the feet of the Divine Child and His Mother? Or was worship simply the pious Knight's godly commencement of the day? Why, too, is the dog so sly looking? Is that little mass of curly white wool a sceptic, doubting his master's good resolutions?" (Sophia Beale in Good Words, July 1895).
[119] Ruskin, in his classification of artists from this point of view, calls them "sensualists," reserving the traditional title "naturalists" to the greatest men, whose "subject is infinite as nature, their colour equally balanced splendour and sadness, reaching occasionally the highest degrees of both, and their chiaroscuro equally balanced between light and shade." This class represents the proper mean. In excess on one side are the "purists" (Angelico, Perugino, Memlinc, Stothard), who take the good and leave the evil. "The faces of their figures express no evil passions; the skies of their landscapes are without storm; the prevalent character of their colour is brightness, and of their chiaroscuro fulness of light." Then in excess on the other side are the "sensualists" (Salvator Rosa, Caravaggio, Ribera), who "perceive and imitate evil only. They cannot draw the trunk of a tree without blasting and shattering it, nor a sky except covered with stormy clouds; they delight in the beggary and brutality of the human race; their colour is for the most part subdued or lurid, and the greatest spaces of their pictures are occupied by darkness" (Stones of Venice, vol. ii. ch. vi.). Elsewhere, Ruskin speaks of Caravaggio and Ribera as "the black slaves of painting" (Elements of Drawing, p. 317).
[120] This is the story told by Dominici, the Neapolitan historian. According to Cean Bermudez, following Palomino (the Spanish historian), Ribera died at Naples honoured and rich.
[121] The tradition that he was a natural son of the Barbarella family, and in consequence called Barbarelli, appears to be unfounded.
[122] "Two figures of Giorgione's are still traceable, one of them (wrote Ruskin in 1846), singularly uninjured, is seen from far above and below the Rialto, flaming like the reflection of a sunset" (Modern Painters vol. i. ed. 3 pt. ii. sec. i. ch. vii. § 30). This beautiful figure was engraved by Ruskin for his fifth volume; he called her from her glowing colour "the Hesperid Aeglé."
[123] Ruskin's seven are Giorgione, Titian, Veronese, Tintoret, Correggio, Reynolds, and Turner (Modern Painters, vol. v. pt. ix. ch. xi, § 8, n).