early painters before the invention and improvement of oil painting. The finer egg tempera in dry climates has been found to attain so firm a consistence as to withstand ordinary solvents. The use of wine in diluting these glutinous vehicles was common for a long period. Buffalmacco, of whom so many humorous stories are told by Boccaccio and Vasari, is related to have persuaded some nuns, for whom he painted, to supply him with their choicest wine, ostensibly for the purpose of diluting the colors, but really to be imbibed by the thirsty painter himself. The northern artists were sometimes compelled to content themselves with beer. In the works of the northern tempera painters there are, however, very marked differences observable in the impasto or body of colors. It is certain, therefore, that these painters employed media of different degrees of consistence. In the distemper of scene-painting, the medium is weak size of glue, but plaster of paris, sufficiently diluted, is worked with the colors. The carbonate of lime, or whiting, is less active as a basis for colors than the pure lime of fresco, but it is entirely destructive of transparency. When the more viscid media were employed by the tempera painters, the effect must, with their purer use of the colors, some of which were, moreover, transparent, have been very lustrous and powerful in comparison with modern scene-painters' distemper, and these qualities were heightened by the addition of a strong varnish; still, however, tempera fell far short of oil painting in richness and transparency.
The carbonate of lime, or whiting, employed as a basis is, however, less active than the pure lime of fresco. The vehicles of both modes are the same, and their practice is often combined in the same work. Water is their common vehicle, and to give adhesion to the tints and colors in distemper painting, and make them keep their place, they are variously mixed with the size of glue, prepared commonly by dissolving about 4 ounces of glue in a gallon of water. Too much of the glue disposes the painting to crack and
