Let us consider the principal colors in detail then, merely as to their actual stability. I
will speak to them in connection with the plates of colors at the end of this book. I would
like you to compare what is said of each color with the corresponding color in the plates.
Those colors in the plates which are not spoken of here, you may consider as useful in
showing you the character of different colors which are made, but which may or may not
be used, according as you may need them. I shall not attempt to mention all the
pigments that are in market. You need never use more than fifteen or twenty all told.
Many painters use more, it is true; but if you know how to make the best use of that
number, you may safely wait till you “grow to them” before you bother with more.
And I shall speak only of those which you will find essential or most generally useful,
and those which should be particularly avoided.
Permanency. - It should be stated what is meant by a permanent color. There is no
color which is not to be influenced in some way. The most sound of pigments will change
if the conditions favor the change. When we speak of a permanent color, we mean only
one which under the usual conditions will stand for an indefinite time. By which is
meant ordinary diffused daylight, not direct sunlight, and the ordinary air under normal
conditions. If there be direct sunlight, you may expect your picture change sooner or
later. But one does not hang his pictures where the sun’s rays will fall on them. If there is
any exceptional condition of moisture in the air, the picture may suffer. Or if from any
cause unusual gases in the atmosphere, or if the picture be too long in a dark, close
place, the picture may smother for lack of fresh air, just as any other thing, plant or
animal, which depends on normal conditions of atmosphere would do.
Let us say, then, that what we mean by permanent color is one which will stand
unchanged for an indefinite length of time in a room which I of the usual condition of
temperature and freedom from moisture, and where the light is diffused, and such that
the direct rays of the sun are not on the picture often, or to any great extent. Cold will
not hurt a picture if the canvas is not disturbed in that condition, but to bend or roll it
while it is very cold will of course crack it, and sudden and extreme changes of
temperature any have the same effect. In other words, some care must be used with all
pictures as a matter of course.
COLOR LIST
Whites. - Zinc White warning is only permanent white, but it lacks body and is little
used. The lead whites, flake, silver, cremnitz, will darken in time, and will turn yellow
with oil, and may change with or affect change in other pigments. The zinc white is liable
to crack. We have no perfect white, so practically you may consider the lead whites as
permanents enough, as other painters do.
Yellows. - Cadmium is permanent in all three of its forms. It is a color the
permanence of which is of great importance; for its brilliancy is quite essential to
modern painting, and if it were not permanent, the picture would soon lose the very
quality for which the color was used. The chromes, which are of similar color-quality,
are less permanent, and are almost sure to turn to a horny sort of yellow; and a green,