tc.

Among the "acid oranges and yellows," we also find a goodly number
which are of medium fastness. About ten, either on wool or on silk,
may even be accounted really fast, and are fit, apparently, to rank
with alizarin colors. Note, for example, on wool: Crocein orange,
aurantia, orange crystal, tartrazin, milling yellow, palatine orange;
on silk, acid yellow D, brilliant yellow, azo acid yellow, metanil
yellow, curcumin S, etc. I may remark that these are some of the
fastest yellows on wool and silk with which we are acquainted. It is
interesting to note the decided fugitive character, on silk, of
tartrazin, aurantia, orange crystal, etc., compared with their great
fastness on wool. Observe, also, how, on wool, the pale lemon yellow
of picric acid has changed to a full reddish brown.

Among the "acid greens and blues," all the colors are fugitive, both
on wool and on silk. Patent blue appears slightly better than the
rest. Of the "acid blacks and violets," a few colors are of medium
fastness, both on wool and silk, e.g., naphthol black, naphthylamine,
black, resorcinol brown, fast brown, etc.

When we examine the Congo colors, amid a number of very fugitive
colors, we find a few which are satisfactorily fast. Among the reds,
for example, diamine fast red is quite remarkable for its fastness,
both on wool and silk, and may certainly rank with alizarin; but on
cotton, it is quite as fugitive as the rest. Of medium fastness on
wool are brilliant Congo G and R, Congo G R; and on silk, diamine
scarlet B, deltapurpurin 5 B, and brilliant Congo R.

Among the "Congo oranges and yellows," we find some of the fastest on
cotton of this class of colors. Still they deserve only the rank of
medium fastness. They are Mikado orange 4 R, R, G. Hessian yellow,
curcumin S, chrysophenin. On wool, we have about half a dozen of
medium fastness, viz., benzo-orange, Congo orange R, chrysophenin G,
chrysamin R, brilliant yellow. On silk, however, we find in this group
about a dozen of the fastest oranges and yellows with which we are
acquainted for this fiber, viz., Congo orange R, chrysophenin G,
diamine yellow N, brilliant yellow, curcumin W, benzo orange, Hessian
yellow, chrysamin R and G, cresotin yellow R and G, cotton yellow G,
and carbazol yellow.

Does it not appear somewhat remarkable that we should find among this
generally fugitive group of coloring matters colors which are so
eminently fast on silk, and which we entirely f