If I were to give you the formula of Magenta you would be
astonished at its complexity and size, but I think now you will see that
it is really built up of aniline derivatives. Methyl Violet is a colour
we have already referred to, and its chemical structure is still more
complex, but it also is built up of aniline materials, and so is a basic
aniline colour. Now it is possible for the colour-maker to prepare a
very fine green dye from this beautiful violet (Methyl Violet). In fact
he may convert the violet into the green colour by heating the first
under pressure with a gas called methyl chloride (CH_{3}Cl). Methyl
Violet is constructed of aniline or substituted aniline groups; the
addition of CH_{3}Cl, then, gives us the Methyl Green. But one of the
misfortunes of Methyl Green is that if the fabric dyed with it be boiled
with water, at that temperature (212 deg. F.) the colour is decomposed and
injured, for some of the methyl chloride in the compound is driven off.
In fact, by stronger heating we may drive off all the methyl chloride
and get the original Methyl Violet back again.
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