Their painting rests upon conventions as audacious as those of their sculpture. In it every surface has an uniform and decided value though in nature everything is shaded. A nude figure is all one colour--dark for a man, light for a woman. A drapery has but one tone, the artist never seeming to trouble himself whether it be in light or shadow, or partly in one partly in the other. In a few plates in Lepsius, and still more in Prisse,[327] there are suggestions that an artist here and there, more skilful than his rivals, understood that values differed, and distinguished in his more careful work between colour in shadow and colour in light. One or two contours appear to hint at the rotundity of chiaroscuro. In accepting such a suggestion, however, we should be making a mistake against which we have been warned even by such early travellers as the authors of the _Description_.[328] The effects in question must be placed to the credit of the sculptor. The images in which they appear are painted bas-reliefs, and the slight shadow thrown by their salient grounds gives an appearance of half-tint to their contours. Wherever pictures are without relief there is no such appearance, and yet changes of value would in them be more useful than elsewhere. [327] Vol. ii. plates 41, 66, and 70. [328] _Description, Antiquités_, vol. iii. p. 45. To place unbroken colours in juxtaposition to each other without transitions is to illuminate; it is not painting in the true sense of the word, and its practitioner is an artisan rather than an artist. The artist is he who traces the design upon the walls, who, chalk in hand, sketches the forms of men and women and the lines of the ornament. Many of these sketches are admirable for the freedom and breadth of their outline. The portrait of Amenophis III. which is to be seen in his tomb in the Bab-el-Molouk is a good example of these master-studies (Fig. 263). When nothing interfered to prevent the completion of the work, the painter came with his palette and brushes to spread colour over the spaces enclosed by these lines. Nothing could be easier than his task. He was only required to lay his colours smoothly, and to avoid overpassing the boundaries laid down for him. The hues of the flesh and of the draperies were fixed in advance as well as those of the various objects which were repeatedly introduced in such works. [Illustration: FIG. 263.--Outline for a portrait of Amenophis III. Champollion, pl. 232.]