861. Methyl violet discovered; manufactured in 1866; leading to a new
use of copper salts as oxidizing agents, and to the manufacture of
dimethylaniline.

1862. Hofmann violets discovered; leading to manufacture of methyl
iodide from iodine, phosphorus, and wood spirit.

1862. Phosphine (chrysaniline) discovered in crude magenta.

1863. Aniline black introduced; leading to a new use for potassium
chlorate and copper salts, and to the manufacture of aniline salt.

1863. Aniline yellow introduced, the first azo-colour.

1864. Induline discovered; leading to new use for aniline yellow.

1866. Manchester brown introduced, the second azo-colour; leading to the
manufacture of sodium nitrite, and of dinitrobenzene.

1866. Iodine green introduced; leading to further use for methyl iodide.

1866. Diphenylamine blue introduced; leading to manufacture of
diphenylamine.

1868. Blue shade of methyl violet introduced; leading to manufacture of
benzyl chloride.

1868. Saffranine introduced.

1869. Nitrobenzene process for magenta discovered.

1876. Chrysoidine introduced, the third azo-colour.

1876. Methylene blue introduced; leading to manufacture of
nitrosodimethylaniline.

1877. Acid magenta discovered.

1878. Methyl green introduced; leading to utilization of waste from
beet-sugar manufacture.

1878. Malachite green discovered; leading to manufacture of benzoic
aldehyde.

1878. Acid yellow discovered; leading to new use for aniline yellow.

1879. Neutral red and allied azines introduced; leading to a new use for
nitrosodimethylaniline.

1883. Phosgene colours of rosaniline group introduced; leading to
manufacture of phosgene.

CHAPTER III.

Among the most venerable of natural dye-stuffs is indigo, the substance
from which Unverdorben first obtained aniline in 1826. The colouring
matter is found in a number of leguminous (see Fig. 7), cruciferous, and
other plants, some of which are largely cultivated in India, China, the
Malay Archipelago, South America, and the West Indies; while others, such
as woad (see Fig. 8), are grown in more temperate European climates. The
tinctorial value of these plants was known in India and Egypt long before
the Christian era. Egyptian mummy-cloths have been found dyed with indigo.
The dye was known to the Greeks and Romans; its use is