The light of the picture, as I observed, ought to be of a warm colour; for though white may be used for the principal light, as was the practice of many of the Dutch and Flemish painters, yet it is better to suppose _that white_ illumined by the yellow rays of the setting sun, as was the manner of Titian. The superiority of which manner is never more striking than when in a collection of pictures we chance to see a portrait of Titian's hanging by the side of a Flemish picture (even though that should be of the hand of Vandyke), which, however admirable in other respects, becomes cold and grey in the comparison. The illuminated parts of objects are in nature of a warmer tint than those that are in the shade; what I have recommended, therefore, is no more than that the same conduct be observed in the whole, which is acknowledged to be necessary in every individual part. It is presenting to the eye the same effect as that which it has been _accustomed_ to feel, which, in this case, as in every other, will always produce beauty; no principle, therefore, in our art can be more certain, or is derived from a higher source. When I just now mentioned of the supposed reason why Ariadne has part of her drapery red, gives me occasion here to observe, that this favourite quality of giving objects relief, and which De Piles and all the Critics have considered as a requisite of the utmost importance, was not one of those objects which much engaged the attention of Titian; painters of an inferior rank have far exceeded him in producing this effect. This was a great object of attention, when art was in its infant state; as it is at present with the vulgar and ignorant, who feel the highest satisfaction in seeing a figure, which, as they say, looks as if they could walk round it. But however low I may rate this pleasure of deception, I should not oppose it, did it not oppose itself to a quality of a much higher kind, by counteracting entirely that fulness of manner which is so difficult to express in words, but which is found in perfection in the best works of Correggio, and we may add, of Rembrandt. This effect is produced by melting and losing the shadows in a ground still darker than those shadows; whereas that relief is produced by opposing and separating the ground from the figure, either by light, or shadow, or colour. This conduct of in-laying, as it may be called, figures on their ground, in order to produce relief, was the practice of the old Painters, such as Andrea Mantegna, Pietro Perugino, and Albert Durer; and to these we may add the first manner of Lionardo da Vinci, Giorgione, and even Correggio; but these three were among the first who began to correct themselves in dryness of style, by no longer considering relief as a principal object. As those two qualities, relief, and fulness of effect, can hardly exist together, it is not very difficult to determine to which we ought to give the preference.