288 PAINTING MATERIALS
certainly known in Pompeian times. Cennini (C. CXL, Thompson, p. 85) speaks of
using compasses for incising the outlines of haloes in the burnished gold of panels.
Modern usage often refers to this instrument in the plural as a pair of compasses.
Copper Point., Though less common than that of silver,, the point or stylus of
copper as a drawing instrument to be used on a prepared surface has had occa-
sional mention in the history of the art. It is said to have a tendency to turn
slightly yellowish as it corrodes on standing. This might depend on the kind of
atmosphere to which it was exposed. A codex in Montpellier (see Meder, p. 74)
mentions the use of a copper point.
Crayon* a small stick for drawing, composed usually of pigment in an oil or
wax. It is smooth and is ordinarily used on paper. Certain crayons of modern
manufacture contain water-soluble dyes and are prepared in an aqueous medium.
Drawings made with these are afterwards washed over with a brush and water to
extend the tones made by the crayon marks. The use of crayons in Europe evi-
dently began in Italy in the middle of the XVI century (Meder, p. 108). Marks of
such a drawing instrument are found in the work of Tintoretto, the Bassani, and
others. They appear in German drawings of the XVI century and are coiUnion in
Europe by the XVII century. One type of crayon was made in the XVII century
by dipping and cooking charcoal in linseed oil.
Crayon Holder. Made as a removable handle for short pieces of charcoal,
chalk, or crayon, this is usually a tube split at both ends and fitted with sliding
rings (figure 7). Into the split part the round chalk or crayon can be placed and
held tightly by the rings slid over the split metal. The common crayon holder is of
brass and is from 4 to 6 inches long, with or without a wooden center. It is ad-
vertised by most dealers in artists' materials but probably had a greater use in
times when the pencil as known today had not yet been devised. Paintings of the
XVI century frequently show it in the hands of artists and draughtsmen, and by
the XVIII century it is found with fair regularity in studio interiors. According to
Meder (p. 185), an earlier form of the holder was a split reed, and the metal tube was
introduced only in the XVI century. Catalogues of artists' materials in the XIX
century list it normally under the name of 'portcrayon/
Cushion. In the process of applying gold leaf, this extremely thin material has
to. be laid out where it can be flattened and frequently be cut. Squares of the gold
are usually dropped from the books, in which modern leaf is put up for the market,
onto a gilder's cushion (figure 12, a). The typical cushion is made over a rectangular
panel of wood, five or six inches wide and eight to ten inches long. A thin padding
is placed over this. Stretched across the pad and pulled tightly over the edge of
the wood a piece of soft calfskin is tacked rough side up. Around three sides of this
cushion a shield four or five inches high is fastened, made ordinarily of parchment
or of heavy paper. This is to prevent draughts of air from disturbing the gold leaf.
The calfskin needs to contain-as little oil as possible, and it is frequently powdered
over with haematite or red ochre to prevent the leaf from sticking. Some form of