The Artist's Assistant, In the Study and Practice of Mechanical Sciences: Calculated for the Improvement of Genius. Illustrated with Copper-Plates (Birmingham, [ca. 1785])

THE ARTIST'S ASSISTANT. 133

Take about half the quantity of lake intended for
the crayons, and grind it very fine with fpirits of
wine; let it dry and then pulverize it, which is
eafily done if the lake is good : then take the other
half, and grind it with fpirits, after which mix it
with the pulverized lake, and lay it out directly in
crayons on the chalk. The colour will not bear
rolling. The fimple colour being thus prepared,
proceed with the compound crayons, as directed be-
fore, and in the fame degrees of gradation as the
carmine teints.

VERMILLION, or NATIVE CINNABAR.

The beft is inclined to the carmine teint. To
prepare this colour mix it on the ftone with foft
water, or fpirits, after which it may be rolled into
crayons.

BLUES.

PRUSSIAN BLUE

Is a colour very apt to bind, and is rendered foft
with more difficulty than carmine and lake. The
fame method of preparation is to be followed with,
this as directed with refpeet to lake, only it is ne-
ceffary to grind a larger quantity of the pure colour,
as it is chiefly ufed for painting draperies.

BLUE VERDITER

Is a colour naturally gritty, and therefore it is
neceffary to wafh it well. Its particles are fo coarfe
as to require fome binding matter to unite them,
otherwife the crayons will never adhere together.
To accomplifh this, take a quantity fufficient to form

two