International studio (58.1916)

Colour Theory

OLOUR THEORY
BY MICHEL JACOBS
In these days of technical knowl-
edge and scientific accuracy, it is a
great wonder why the artist still follows the old
law of colours and their complementaries as dem-
onstrated by Newton & Brewster, based on the
theory that the colours red, blue and yellow were
primary colours, and the secondary colours were
green, purple and orange. This theory has long
since been discarded by scientists, and the new
theory adopted, as laid down by Young,
Helmholtz and Tindall, that the primary colours
are red, green and violet. The Newton-Brewster
theory is based on the mixture of _._
pigments and the Young-Helm-
holtz on the spectrum.
When we see an object
that is a certain colour in
a white light, the shad-
ows of that object as-
sume the comple¬
mentary colour to
the colour of the
lighted side, as
Monet discovered.
This all modern art-
ists understand. The
question is, what is
the complementary of
any colour? What is un-
derstood by complemen-
tary colour is that one of the
primaries is complementary
the other two primary colours com-
bined. Now, should we use the old
Newton or the Helmholtz one, which is based on
scientific truth?
It is true to a certain extent that we cannot
mix red and green pigments and make a yellow,
but with the rays of light it is possible to combine
the red rays with the green rays and secure a
brilliant yellow. Also to combine green with a
violet light and make a brilliant blue, etc. Why
painters should change the laws of colour as
seen in the spectrum and their complementaries
because the chemical properties of the pigments
on their palette do not mix the same as the rays
of light, one fails to understand, although it is
possible with certain chemicals to follow out
exactly the laws of the spectrum.

Art is nature seen through a personality. If
it is the desire of the artist to imitate nature as
closely as possible, at any rate in regard to colour,
he must be conversant with all the laws of colour
by which nature is governed. Undoubtedly if
an artist tries to paint scientifically and does not
really see the colours which he paints, his work
will be of no use artistically. But he must be
taught to see colour the same as he has been
taught to see form.
Nature has given us, in our eyes, three sets of
nerves corresponding to the colours of the spec-
trum; one set is sensitive to green rays, one to
red and one to violet. If the violet and green
nerves are set in vibration, we see, not green and
violet separately, but blue, and if the
green and red, we see yellow,
etc. Let us see what a dif-
ference it makes when we
take the spectrum as our
guide or our palette;
which to me is only
a chemical labora-
tory from which we
make a certain com-
bination of chemi-
cals to reflect cer-
tain colours of the
spectrum. Say, for
example, we are paint-
ing an object red; ac-
cording to the laws of
the spectrum the shadow of
that object should be toward
the blue because blue in the
spectrum is composed of the green
and violet rays of light and must be complemen-
tary to the third primary, red. According to the
laws of pigments as laid down by Newton-
Brewster, the shadows of a red object should be
toward the green, because green is composed of
yellow and blue pigments, and must be com-
plementary to the third primary, red, as Monet
set forth.
To arrive at an understanding of complemen-
taries let us say that the spectrum is represented
by ioo which is divided into three equal parts,
red, green and violet, each represented by yCA
per cent, of the whole of the spectrum. Suppose
we take, for example, a full yellow which is com-
posed of all the red rays (33J/3 per cent.) and all
the green rays (33Jj per cent.), which means yel-


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