REDS.—It is rather difficult to procure either good carmine or good lake. Good carmine is inclined to the vermilion tint, and good lake to the carmine tint. The carmine crayons are prepared in the following manner.
1. Carmine. As their texture is inclinable to hardness, instead of grinding and rolling them, take a sufficient quantity of carmine, lay it upon the grinding-stone, mix it by means of a levigating knife with spirit of wine till it becomes smooth and even. The stucco stone being ready, lay the colour upon it to absorb the spirit; but be careful that it is laid on in a proper state for painting. If it is levigated too thin, the crayons will be too flat; and if too thick, it will occasion a waste of colour, by their adhering to the pallet-knife; but practice will render the proper degree of consistency familiar. The simple colour being prepared, the next step is to compose the different tints by a mixture with whiting; and the proportion to be observed, consisting of twenty gradations to one, may be clearly understood by the following directions: Take some of the simple colour, and levigate it with spirit of wine, adding about one part of washed whiting to three parts of carmine, of which, when properly incorporated, make two parcels. The next gradation should be composed of equal quantities of carmine and whiting, of which four crayons may be made. The third composition should have one fourth carmine and three fourths whiting; of this make six crayons, which will be a good proportion for the rest. The last tint should be made of whiting, very faintly tinged with carmine, of which make about eight crayons, which will complete the above-mentioned proportion. As these compound tints are levigated, they are to be laid immediately upon the stucco, that the moisture may be absorbed to the proper degree of dryness for forming into crayons, which may be known by its losing the greater part of its adhesive quality when taken into the hand; if the consistence is found to be right, it may be then laid upon the glass, which, having no pores, will
prevent the moisture from being carried off before it is convenient to form it into crayons, otherwise the crayons would be full of cracks and very brittle, which will be a great inconvenience when they are used in painting.
2. Lake. This is a colour very apt to be hard; to prevent which the following particulars must be observed: Take about half the quantity of lake intended for the crayons, and grind it very fine with spirit of wine; let it dry, and then pulverize it, which is easily done if the lake is good; then take the other half, and grind it with spirits, after which mix it with the pulverized lake, and lay it out directly in crayons on the stucco. This colour will not bear rolling. The simple colour being thus prepared, proceed with the compound crayons as before directed, and in the same degrees of gradation as the carmine tints.
3. Vermilion. The best is inclined to the carmine tint. Nothing more is required to prepare this colour than to mix it on the stone with soft water or spirits, after which it may be rolled into crayons. The different tints are produced by a mixture of the simple colour with whiting, according to the proportion already given.