ill be a
fundamental one in landscape. A landscape which you cannot breathe in
is not a perfect one. We live and breathe in atmosphere, and the
expression of atmosphere will go far to make your landscape true. But
atmosphere is not haziness. Neither is it vagueness nor negativeness
of color. Truth of color-quality, and justness of relation will do
most in getting it. You had better not try for atmosphere as a thing,
but as a result. Anything so universal and so indefinite can be
expressed by no one thing. If you try to get it by any one means you
will miss it. Study, then, the subtlety of color relation and justness
of value. Try to be sensitive to the slightest variety of tone, and be
satisfied with no least falsity of rendering, and you will find that
your picture will not lack atmosphere.

=Color of Contour.=--An important thing for you to look for and to
study is the color of contours. You will not find it easy; not easy
even to know what it is that you are looking for. But consider it as a
combination of contiguous values and color vibrations, and things will
reveal themselves to you.

No form is composed of unvarying color. No combination of color
surrounding it lacks variety. All along the edge of forms and objects,
of whatever kind, the value and color relation constantly change. The
outline is not constant. Here and there it becomes lost from identity
of value and color with what surrounds it, and again defines itself.
The edge is not sharp. The color rays vibrate across each other. The
inevitable variety of tint and value, of definiteness and vagueness,
gives a never-ending play of contrasts and blendings. These are
qualities which go to the harmonizing of color, to the expression of
light, and particularly to the feeling of atmosphere. This constant
variety of contrasting edges is the constant movement and play of the
visual rays, and the study of it gives life and vibration to the
picture, and all the objects represented in it.

Outdoors, particularly when the play of diffused light and the
movement of all the objects is continually felt, either through their
own elasticity or because of the heat and light waves, this study is
most necessary, if you would get the feeling of freedom, space, and
air.

=Skies.=--In the painting of the sky there are several points to be
kept in mind. The sky, even on the quietest day, is full of movement.
Cloud masses change continually. If there are no clouds there is
con