Chapter 10 CRAYON

Chemical or fatty crayon is a composition intended to be used on the stone plate in dry form like Spanish or Parisian chalk. The inks described previously have the property of soaking into the stone and making it greasy where applied. The same happens if they are applied dry, the degree of their penetration and adherence merely being less.

The mixtures that may be used to make crayons are countless. Wax and soaps, however, are better than resinous materials. Therefore it is likely that the compositions here named will be pretty nearly the best.

(1) Wax 4 parts

Soap 6 parts

Lampblack 2 parts, roasted, or better still, made as explained before.

The wax and soap are melted together. The lampblack is added then. All is rubbed down fine on a hot plate, and then placed on the fire again till it is fluid once more. Then it is poured on a stone plate coated with a little oil, so that it forms a cake of about one eighth inch thickness. When this has cooled a little, it is cut into thin pieces and put away till needed.

(2) Wax 8 parts

Soap 4 parts

Lampblack 2 parts

Burn the wax till one half is consumed, then melt the soap with it, and treat the mixture as before.

(3) Wax 4 parts

Spermaceti 4 parts

Soap 4 parts

Lampblack 2 parts

The first three materials are melted together, the lampblack is added, and then the whole is treated as before.

(4) Wax 8 parts

Spermaceti 4 parts

Soap 4 parts

Lampblack 2 parts

The wax is to be half burned away, then the spermaceti and soap are to be melted into it, and the whole treated as the other formulas.

(5) Shellac 4 parts

Wax 8 parts

Soap 5 parts

Lampblack 3 parts

The shellac is to be completely dissolved with the wax by means of combustion after which the rest of the treatment is the same as before.

(6) Shellac 4 parts

Wax 8 parts

Tallow 2 parts

Soap 5 parts

Lampblack 3 parts

The same treatment, except that the tallow is to be mixed in after the shellac has dissolved. This crayon is a little softer than the others. The same is true of the following two.

(7) Wax 8 parts

Tallow 4 parts

Soap 6 parts

Lampblack 3 parts

Wax, tallow, and soap are melted together and burned till one third of the mass has been consumed. Then the lampblack is added and the rest of the process is as before.

(8) Wax 2 parts

Tallow 6 parts

Mennig 2 parts

Lampblack 2 parts

Wax, mennig, and lampblack are heated and constantly stirred till the mennig dissolves in froth and changes from red to brown. Then the lampblack is rubbed in thoroughly, the whole warmed again properly and shaped into sticks.

These are the best compositions, thoroughly tested by me, and it is very good to make a stock of all or most of them. In the case of the recipes for chemical ink, the differences are not great, and it is largely a matter of taste as to which kind one may use. But in the case of the crayons, each of them produces a different grain which creates a particular effect; so that by using various kinds of crayon one will gain greater perfection of work, or, at least, find execution easier than with only one crayon. Also, they are in proportion to the greater or lesser roughness of the stones; and the darker shadings are easier to produce with soft crayons than with hard ones, while the hard ones are best for fine shading and outlines.

The lampblack used for crayons must be burned out first, else it will develop blisters, which is the case also if the composition is poured on the plates too hot.

Crayon that contains much shellac is likely to soften in damp air; therefore it should be kept in tightly closed vessels.