d upon, so that the less space of light and the greater the
space of dark, the more brilliant would be the main spot of light in
the picture. They wrought with the _quality of light and shade_ as an
_element_, just as they would with the quality of line or of color,
considered apart from objects or facts they might represent.

=Arbitrary Lighting.=--This is the arbitrary light and shade spoken of
in the chapter on "Values"; and although the older painters included
what we now call values in their word chiaroscuro, it is this fact of
arbitrary lighting as opposed to accepting the light as it does fall,
or selecting those places or times where it does naturally fall as we
would like it to, that makes the difference between modern painting
generally and the older method, and has made chiaroscuro as a word and
as a quality of painting so much a thing of the past.

=Light and Shade.=--But we may use the old word with a more
restricted meaning. If we use it to mean literally light and shade,
the way light falls on objects and the relief due to the light side
and the shadow side of them, we get a use which implies a very
important and practical matter for present study.

[Illustration: =Eggs. White against White.=]

=Objects Visible by Light and Shadow.=--If you will put a white egg on
a piece of white paper, with another white paper back of it, you will
see that it is only because the egg obstructs the light, the side of
it towards the light preventing the light rays from touching the other
side, and so casting a shadow on itself and on the paper, that the egg
is visible. You will also see, if you manipulate the egg, that
according as the light is concentrated or diffused, or according to
the sharpness of the shadow and light, is the egg more or less
distinct.

=Contrast.=--Apply these facts to other objects, and you will see how
important the principle of contrast is to the representation of
nature. Not only contrast of light and shade, but contrast of color.
And you should make a study, both by setting up groups of objects in
different lights, and by studying effects of lights wherever you are,
of the possibilities and combinations of light and shadow.

=Constant Observation.=--The painter is constantly studying with his
eyes. It is not necessary always to have the brush in your hand in
order to be always studying. Keep your brain active in making
observations and considering the relations in nature around you. The
a