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French white chalk, is foft and adapted only for
larger fubjedts, as are all the chalks, of France; its
black chalk is only fit to be ufed where expedition
admits of -flumping, Confiderable quantities of Spanish
chalk are imported, which is in .texture between the
foregoing, but not very fmooth.

Red chalk, is very much ufed in defign ; it is in
general of a kind and moderate temper and readilv forms
a grain. It is however, very far from cleanly in its na-
ture, -and is apt to fmear and ftain whatever it touches;
the precautions neceflary to guard againft this quality,
in fact contribute to its ufefulnefs, fince whoever having
been habituated to red chalk can draw clean with it, is
fecure from injury by other materials.

Red chalk is beft ufed fimply on white paper, but fome
fhadow it with black chalk, or ftump in black chalk
nrft into the fhades, and proceed with red.

Black and white chalks mutually affift each other on a
paper whofe colour ferves for a demi tint. Price varies
according to quality, from 6d. per oz. to is. 6d, The bad
is quite worth!efs. To be good, it fhould be free from
grit, and not too hard.

CLAIR-OBSCURE, is a term ufed to exprefs the
management and conduct of light in producing effect.
As it is a very important principle of art, its confidera
tion will occur in its proper place at large.

CLAIRO-OBSCURO, or Chiaro Obscuro, is
ufed to denominate a defign made in two colours cniv,
ordinarily black and white ; in which, variety of colours
cannot contribute to effect, but it muft be produced by
other means.

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