Materials. 305 and staining wall-papers, although the old masters often executed portions of their pictures in distemper, and oiled them afterwards. Towards the close of the middle ages, the Italians discovered that by using albumen, or white of egg, instead of size, as a means of union between the particles of colouring matter, they obtained a better substance for tempera painting and one less liable to be affected by damp than materials dissolved in water. Paintings in this medium, however, dry too quickly for any elaborate working-up, and require some kind of varnish to protect them. Painting in Oils. — As early as A.D. 1000, linseed-oil was used in painting in Italy, and there are records which prove that oil was used as a medium in painting in Germany, in France, and even in England before the time of the Van Eycks ; but it was not until the fifteenth century that the best method of mixing colours with oil was discovered by the brothers Van Eyck, who quickly attained to a skill in colouring perhaps never surpassed. The old method practised by the Italians did not allow of one colour being laid on until the previous coat had dried ; and it was this inconvenience that caused Jan van Eyck to make experiments which resulted in the discovery of a better kind of oil painting, a kind which has practi- cally prevailed until the present day. This new process was first adopted in Italy by Antonello da Messina and the painters of Naples. How or by whom it was intro- duced to North Italy is not certain. The implements required by a painter in oils are charcoal, chalk, or pencils for drawing his sketch; hair- pencils or brushes; a knife to mix, and a palette to eha x
