■white of the grounds be formed Irom the calx of
tin or antimony, and not arfenic.
Pit-coal3 as was above obferved, may be employed
for burning as well the colours as the grounds, where
the muffle or coffins are ufed ; or any other method
purfued that wholly hinders the fmoke and fumes
from having any accefs to the enamel.
Of ENAMEL PAINTING.
NAMEL painting differs from all other kinds,
in the vehicle employed for the colours (to hold
the parts together, and bind them to the ground they
are laid upon) ; this is glafs or fome vitreous body,
which being mixed with the colours, and fufed, or
melted, by means of heat, becomes fluid; and hav-
ing incorporated with the colours in that ftate, forms
together with them, a hard mafs when grown cold.
It anfwers, therefore, the fame end in this, as oil,
gum-water, fize, or varnifh, in the other kinds of
The glafs or vitreous body, applied to this purpofe
of mixing with the colours, in order to bind them to
the grounds, is called a flux ; and ma&es one of the
principal fubftances ufed in enamel painting. When
this flux is eahly fufible, that is to fay, melts with a
lefs degree of heat, it is, in the ftile of thofe who work
in enamel faid to be foft, and when it is reluftant to
melt, and requires a greater degree of heat, it is called
hard. Thele terms are as well applied to the matter
of the enamel grounds, and all other vitreous fub-
ffances concernedj as to the fluxes. It is, in general, a