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Various

"Scientific American Supplement, No. 810, July 11, 1891"


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,
synonymous with "fugitive color." But science is progressive, fields
of investigation other than aniline have been opened up, so that now,
although a large number of fugitive dyes are still manufactured from
coal tar, there are others, as we have seen, which are as fast and
permanent as we have ever had from natural sources.
Finally, and perhaps this is the most important cause of all, many of
the fugitive coal tar colors are gifted, I will not say with fatal
beauty, but with a facility of application, and such comparative
cheapness in consequence of their intense coloring power, that the
dyer, tempted by competition, applies them not unfrequently to
materials for which, because of their ultimate uses, they are
altogether unsuited; and so it comes about that we find the most
fugitive colors applied indiscriminately and without due discretion.


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