the former the principal were
fresco, al fresco; and the various kinds of distemper (a tempera),
with glue, with the white of egg, or with gums (a guazzo); and with
wax or resins when these were rendered by any means vehicles that
could be worked with water. Of the latter the principal was through
fire, termed encaustic.

Fresco was probably little employed by the ancients for works of
imitative art, but it appears to have been the ordinary method of
simply coloring walls, especially amongst the Romans. Coloring al
fresco, in which the colors were mixed simply in water, as the term
implies, was applied when the composition of the stucco on the walls
was still wet (udo tectorio), and on that account was limited to
certain colors, for no colors except earths can be employed in this
way.

The fresco walls, when painted, were covered with an encaustic
varnish, both to heighten the colors and to preserve them from the
injurious effects of the sun or the weather. Vitruvius describes the
process as a Greek practice. When the wall was colored and dry, Punic
wax, melted and tempered with a little oil, was rubbed over it with a
hard brush (seta); this was made smooth and even by applying a
_cauterium_ or an iron pan, filled with live coals, over the surface,
as near to it as was just necessary to melt the wax; it was then
rubbed with a candle (wax) and a clean cloth. In encaustic painting
the wax colors were _burnt into_ the ground by means of a hot iron
(called cauterium) or pan of hot coals being held near the surface of
the picture. The mere process of burning in constitutes the whole
difference between encaustic and the ordinary method of painting with
wax colors.

We shall now say a few words with regard to the much canvassed
question of painting or coloring statues. Its antiquity and
universality admit of no doubt. Indeed, the practice of painting
statues is a characteristic of a primitive and workmanship of clay or
wood. It was a survival of the old religious practices of daubing the
early statues of the gods with vermilion, and was done to meet the
superstitious tastes of the uneducated. Statues for religious purposes
may have been painted in obedience to a formula prescribed by
religion, but statues as objects of art, on which the sculptor
exhibited all his genius and taste, were unquestionably executed in
the pure and uncolored marble alone. In the chryselephantine, or ivory
statues of Jove and Minerva, by Phidias,