Gobelin tapestries pale shades on wool are frequently obtained by the
use of more or less unchangeable metallic oxides and other mineral
colors, to the exclusion of even fast vegetable dyes.

It is interesting to examine what is the action of light upon compound
colors. Is a fugitive color rendered faster by being applied along
with a fast color?

My own opinion, based upon general observation, is that it is not, and
that when light acts upon a compound color the unstable color fades,
while the stable color remains behind. A woaded color, for example, is
only fast in respect of the vat indigo which it contains, and yet how
frequent is the custom to unite with the indigo such dyes as barwood,
orchil, and indigo-carmine, the fugitive character of which I have
pointed out.

Having thus rapidly surveyed these numerous coal tar colors, both in
their dyed and exposed conditions, I again ask why are they so
generally regarded as altogether fugitive?

First, because we have, especially among these "direct dyes," a very
large number which are undoubtedly very fugitive.

Moreover, all the earlier coal tar dyes--mauve, magenta, Nicholson
blue, etc., belonged to a class which, even up to the present time,
has only furnished us with fugitive colors. They were indeed prepared
from aniline, and it appears to me that the defects of these early
aniline colors, as well as their designation, have been handed down to
their successors without due discrimination, so that in the popular
mind the term "aniline color" has become, as a matter of habit,