For three‐value studies one may use ink, charcoal or oil paint. The two
latter are particularly suitable for landscape designs and illustrative
work. Charcoal should be used lightly and very freely. It gives effects of
vibration, atmosphere, envelope and light, but the handling requires
special study and much practice.
The first few exercises in charcoal landscape may be in flat tones (see
No. 55, page 85), and the student may find it well to make a scale of
three values in this medium; he must learn however to feel outlines
without drawing them, and to handle charcoal firmly but loosely.
Cover the paper with a very sketchy tone of soft charcoal; pass over it
lightly with a paper stump or piece of cotton cloth. Be careful not to
grind the black into the paper, making an opaque smoky tone. Charcoal
paper is made rough, to let the warm white shine between the little
particles of black that lie upon the points of the surface.
[Flower design.]
When a luminous middle‐gray is obtained, sketch in the darks with soft
charcoal and take out the lights with bread or rubber; this effect is like
a mezzotint, Nos. 55, 57, and p. 57. After the principle of three values
has been demonstrated, and the student can appreciate definite intervals
of tone, the instructor should allow great freedom in execution, not even
limiting to three notes but adding one or two others if necessary to good
expression.
For oil painting, mix the three tones in quantity sufficient to paint
several studies. Ivory Black and Burnt Sienna will give a good neutral
gray. For the color of blue china or the Abruzzi towels, use Prussian
Blue, Black and White. Opinions differ as to the use of diluting mediums,
and sizes of brushes, for oil painting. I should advise thinning the color
with linseed oil and turpentine (half and half), and using large flat
bristle brushes. Canvas should be fairly rough in texture. If the surface
to be painted on is smooth,—either wood, pasteboard, or canvas,—prepare a
ground with thick paint, leaving brush‐marks.