The Painter in oil

The tone painter deals with close intervals. He is in love with subtle harmonies.
What he loves is the essence of the color quality, and not its splendor. With the
closest range he can give all possible half-tones and shades and modulations of color,
yet never exceed the gray note perhaps; never once go to the full extent of his palette-
power.
The utmost delicacy of perception and feeling, and the most perfect command of
materials and of values, are necessary to such a painter. Above all, is he the
“painter’s painter,” for the infinite subtlety and the exquisiteness of power are his.
And yet this is the thing least appreciated by the lay mind, the most difficult to
encompass, and requiring the most knowledge to appreciate.
Scientific Color. - To the scientist color is simply the irritation of the nerves of
the retina of the eye by the waves of light. Different wave lengths give different color
sensations. It is the generally accepted theory now that there are three primary
sensations; that is, that the eye is sensitive to three kinds of color, and that all other
shades and varieties of color are the results of mingling or overlapping of the waves
which produce those three colors, and irritating more or less the nerves sensitive to
each color simultaneously. These three primary colors are now stated to be red, blue,
and green. The older idea was that they were red, blue, and yellow; and was based on
experiments with pigments. Pigments do give these results; for a mixture of blue and
yellow pigment will give green, and a mixture of red and green pigment will not give
yellow, while the reverse is the fact with light.
White light is composed of all the colors. And the white light may be broken up
(separated by refraction or the turning aside of light rays from their true course) into
the colors of the rainbow, which is itself only this same decomposition of light by
atmospheric refraction. Black is the absence of light, and consequently of color. This
is not the case with pigment, for pure pigment has never been produced. The
pigment simply reflects light rays which fall on it; that is, pigments have the power
of absorbing, and so rendering in- visible, certain of the rays which, combined, make
up the white light which illumines them; and of transmitting others to the eye by
reflection. We see, that is, our nerves of sight are irritated by, those rays which are
not absorbed, but which are reflected.
All pigment is more or less, absorbent of color rays, and more or less reflective of
them; certain color rays being absorbed by a pigment, and certain other rays being
reflected by it. The pigment is named according to those rays which it reflects.
As a color-producing substance, then, the pigment is practically a mirror reflecting
color rays. But a true mirror would reflect all rays unmodified. If we could paint with
mirrors, each of which would reflect its own color unsullied, we could do what the
scientist does with light; but the painter deals with an imperfect mirror which gives
no color rays back unsullied by rays of another class, and so our results cannot be
the same as the scientist’s. So that just in accordance with the degree of purity of
transmitting power of a pigment will be the purity of the color which we get by its
use. But absolute purity of pigment we cannot get, so we cannot deal with it as we do
with light, and we deal with a practical fact rather than a scientific fact, as painters.