of coal.
By a very simple experiment a little of a very fine violet dye can be
made from mere traces of the materials. One of the raw materials for
preparing this violet dye is a substance with a long name, which itself
was prepared from aniline. This substance is
tetramethyldiamidobenzophenone, and a little bit of it is placed in a
small glass test-tube, just moistened with a couple of drops of another
aniline derivative called dimethylaniline, and then two drops of a
fuming liquid, trichloride of phosphorus, added. On simply warming this
mixture, the violet dyestuff is produced in about a minute. Two drops of
the mixture will colour a large cylinder of water a beautiful violet.
The remainder (perhaps two drops more) will dye a skein of silk a bright
full shade of violet. Here, then, is a magnificent example of enormous
tinctorial power. I must now draw the rein, or I shall simply transport
you through a perfect wonderland of magic, bright colours and apparent
chemical conjuring, without, however, an adequate return of solid
instruction that you can carry usefully with you into every-day life and
practice.
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