B 0 0 K . VII.
CHAPTERX.
Of factitious Colours, and of Black,
NOW proced to foch as are made from things of anotherkind, which, by being wrought,
are changed, and acquire the properties of colours: and first, I fhall speak concerning black.
of great use in all works, that the true manner in which it is prepared and tempered may
be known.
A place is built like à laconicum, and lined with marble smoothened and polished; before
this is built a little furnace, having holes into the laconicum, and the mouth of which is to
be very carefully closed, that the flames may not pass outward; then resin is put into the fur-
nace, the smoke from which is, by the fire, forced through the holes into the laconicum, where
it adheres to the walls and curve of the dome; whence being collected, part thereof is levigated
with gum, to make ink for the use of the copyers of books; the rest is mixed with size,
and used for colouring the stucco on walls.
But if these materials cannot be procured, that the work may not be delayed, it will be
necessary to proceed thus: twigs or chips of the pine tree are to be burned, and the coals,
when extinguished, are to be pounded in a mortar with glue, which will make a black for
the stucco work, not displeasing: so likewise the lees of wine dried and burnt in a furnace,
being ground together with glue, and laid on the work, makes an agreeable black; and
the better the wine was, from which it was prepared, the black will not only be better,
but will even approach the colour of indicum.
(1*) The laconicum is mentioned in the 10th chapter
of the 5th book.
(2*) Pliny, b. 35. chap. 6. mentions this black, made
from the lees of wine, in the same manner; but says the
most esteemed black was that made from the teda or
pine, which was adulterated with the soot from furnaces,
or the baths: he speaks also of the black made of burnt
ivory, called elephantinum, and of some earths which are
naturally black.