In the Theban tombs the figures are first drawn and then painted upon a fine coat which has all the polish of stucco. It seems to consist of a very fine plaster and a transparent glue. It is still white where no tint has been laid upon it; here and there its shining surface is still undimmed.[332] When the pictures were executed upon wood or, as in the mummies, upon linen laid down upon a thin layer of plaster, a preparatory coat of white was always spread in the first instance. The tints became more brilliant over such a coat, the most opaque being in some degree transparent.[333] [332] _Description, Ant._ vol. iii. p. 44. [333] MÉRIMÉE, _Dissertation sur l'Emploi des Couleurs_, p. 130. The paintings are, as a rule, free from cracks. The colours seem to have been mixed with water and some flexible gum like tragacanth.[334] M. Hector Leroux, who took impressions of many bas-reliefs during his visit to Egypt, is inclined to believe that the Egyptians sometimes mixed honey with their colours, as the makers of water-colours do now. In some of the tombs the painting became sticky when he laid his moistened paper upon their surfaces. In others no amount of wetting affected the surface of the colours, which remained as smooth and hard as enamel. Some Egyptian paintings are covered with a resinous varnish which has blackened with time and spoilt the colours upon which it is laid.[335] The same varnish was used for the mummy cases and gives them the dark hue which they now present. A few exceptionally well preserved examples permit us to suppose that their colours when fresh must have been much lighter in tone and more brilliant than they now appear. No such precaution was taken, as a rule, in the case of the frescos. Their surfaces were left free from a substance that could so greatly alter with time, and thanks partly to this, partly to the equality of temperature and to the dryness and tranquillity of the air, they have retained an incomparable freshness. The centuries have passed gently over them, but since all the world has taken to visiting Egypt, including even the foolish and ignorant, they have suffered greatly from the barbarity of tourists. Of this the state of those beautiful decorations in the tomb of Seti which have excited the admiration of all cultivated travellers, is a painful instance. [334] MÉRIMÉE, _Dissertation_, etc. Champollion uses the term _gouache_, body colour, in speaking of these paintings, but as the characteristic of that process is that every tint is mixed with white, there is some inaccuracy in doing so. [335] PRISSE, _Histoire de l'Art Égyptien_, text, p. 291. Several mummy masks are in existence which prove that encaustic painting, in which naphtha and wax were used, was employed by the Egyptians;[336] but this process does not seem to have been developed until after the Macedonian conquest. Speaking generally, we may say that the Egyptian method was _distemper_.