THE CHEMISTRY
OF PAINTS AND PAINTING
INTRODUCTION
The materials employed by 'picture-makers' are now very numerous. Some of the old pigments, and painting-grounds, and methods, have indeed fallen more or less completely into disuse; but, on the other hand, many new products, both natural and artificial, have been added to the resources of the artist, while several new processes of painting have been introduced, or old methods modified. Nowadays it is very seldom that a painter prepares for himself any one of the materials which he uses, generally accepting, without much hesitation and without examination, the paper, the canvas, the paints, the oils, and the varnishes which his colourman supplies, provided they respond, at first sight, to his requirements. True he has abandoned, not without regret, several of the most treacherous compounds by which his immediate predecessors were seduced. 'Pure scarlet' he has given up; he is shy of asphalt; tobacco-juice and Spanish liquorice are no longer regarded as desirable water-colours. He may go so far as to reject chromate of lead, but he still employs the pigment called chrome green, or green cinnabar, for he does not know that the
