Amline, a substance discovered in 1826 by O. Unverdorben, in the distillation of indigo. At the present time it is almost exclusively prepared by the deoxidation of nitro-benzole by means of nascent hydrogen evolved from iron filings and acetic acid. This operation is graphically represented by the following formulas: C6H5NO2 (nitro-benzole) + 611 = C6IH7 N (aniline) 4- 2H20. Aniline is a colorless oily liquid, of a vinous aromatic odor, and bitter burning taste, and in the air turns brown. Its specific gravity is 1,028. It is slightly soluble in water, to which it imparts a weak alkaline reaction. Alcohol, ether, and the fatty oils dissolve it in all proportions. It solidifies at - 8° C, boils at 182° C, and combines with acids and forms salts soluble in water and alcohol. The faintest trace of aniline can be detected by the deep purple violet color which chloride of lime produces with it. It is an active poison, but its salts are said to be harmless. In 1856 Mr. Perkin, while experimenting with aniline, discovered the beautiful purple dye, which was soon introduced into commerce under the name of mauve.

Since that time a variety of colors have been produced, and the manufacture of .aniline has become an industry of great importance.