Again, the works of the colourists show that these oppositions are not confined to large masses (except perhaps in works to be seen only at a great distance); on the contrary, they are more or less apparent in every part, and when at last the direct and intentional operations of the artist may have been insufficient to produce them in their minuter degrees, the accidental results of glazing and other methods may be said to extend the contrasts to infinity. In such productions, where every smallest portion is an epitome of the whole, the eye still appreciates the fascinating effect of contrast, and the work is pronounced to be true and complete, in the best sense of the words. The Venetian method of scumbling and glazing exhibits these minuter contrasts within each other, and is thus generally considered more refined than the system of breaking the colours, since it ensures a fuller gradation of hues, and produces another class of contrasts, those, namely, which result from degrees of transparence and opacity. In some of the Flemish and Dutch masters, and sometimes in Reynolds, the two methods are combined in great perfection. The chromatic diagram does not appear to be older than the last century. It is one of those happy adaptations of exacter principles to the objects of taste which might have been expected from Leonardo da Vinci. That its true principle was duly felt is abundantly evident from the works of the colourists, as well as from the general observations of early writers.[5] The more practical directions occasionally to be met with in the treatises of Leon Battista Alberti, Leonardo da Vinci and others, are conformable to the same system. Some Italian works, not written by painters, which pretend to describe this harmony, are, however, very imperfect.[6] A passage in Lodovico Dolce's Dialogue on Colours is perhaps the only one worth quoting. "He," says that writer, "who wishes to combine colours that are agreeable to the eye, will put grey next dusky orange; yellow-green next rose-colour; blue next orange; dark purple, black, next dark-green; white next black, and white next flesh-colour."[7] The Dialogue on Painting, by the same author, has the reputation of containing some of Titian's precepts: if the above passage may be traced to the same source, it must be confessed that it is almost the only one of the kind in the treatise from which it is taken. [1] "Ardito veramente alquanto, sanguigno, e quasi fiammeggiante."--_Zanetti della Pittura Veneziana_, Ven. 1771, p. 90. Warm as the flesh colour of the colourists is, it still never approaches a positive hue, if we except some examples in frescoes and other works intended to be seen at a great distance. Zanetti, speaking of a fresco by Giorgione, now almost obliterated, compares the colour to "un vivo raggio di cocente sole."---_Varie Pitture a fresco dei Principali Maestri Veneziani_. Ven. 1760. [2] Ridolfi. [3] Zanetti, I. ii.