s darker than some bit of light in
the landscape, you will find, if you can manage to get them to tell
against each other, will be the more luminous of the two, and will
look lighter. There are times when the sun glares on a white building
or a piece of white sand, when the white tells light against the blue.
But these are exceptions, and if we could get a blue paint which would
give the intensity of color, and also the brilliancy of the light,
even these cases would be most truly represented with the sky as the
higher value. It is a case of whether to sacrifice value to color, or
the reverse, as we cannot have both.

Sometimes, however, in a storm, the dense dark of the storm sky is
really lower in value than some white object against it, especially if
there be a bit of sun breaking through on it.

But in general, nevertheless, you should consider the sky as always
lighter and more luminous than anything under it.

=Three Planes.=--It will help you in understanding the way the light
falls on landscape to consider everything as in one of three planes,
and these planes taking greater or less proportions of light according
to the position of the sun with reference to them.

The position of the sun changes from a point immediately over, to a
point practically at right angles to all objects in nature. Everything
that can exist under the sun will come in one of these planes, and at
some time in the day in each. The vertical, the horizontal, or some
sort of an oblique between these two. If the sun is overhead exactly,
the flat ground, the tops of trees and houses, will get the full
amount of sunlight. The vertical planes, sides of houses, depths of
foliage, etc., will get the least, some of them being lighted only by
diffused and reflected light. The planes lying between these two
extremes will get more or less, according as they are more or less at
right angles to the direct rays of the sun. And as the sun declines
from the zenith, the vertical planes get more and more and the
horizontal planes less and less of the light, till in the late
afternoon the banks of trees and sides of buildings and cloud-masses
are gilded with light, and the broad horizontal plains of land and
water are in shadow.

However obscured the sun may be, this principle holds more or less;
and it makes clear and helps you to observe and notice many facts in
landscape light and shade which it is necessary to know.

Millet said that all the beauty o