Improved Magenta Color.

Scientific American 13, 10.12.1853

Intense activity is manifested by European chemists, at present, in the production of improved aniline colors. Dr. Dawson, of Huddersfield, England, has obtained a patent for producing magenta, or aniline purple, as follows: - Equal parts of aniline and arsenic acid are mixed together, with about 28 per cent of boiling water. This is placed in a strong iron cylinder capable of withstanding a pressure of 200 pounds on the inch. The lid of the cylinder is now bolted on and the temperature of its contents raised to 850° Fah. [voi olla 350°; kirjasin kulunut]; and maintained at this heat for twelve hours, when the desired color is obtained. The product is then taken out, washed with water, and is ready to be dissolved in alcohol, in which state it is fit for dyeing.

The production  of a pure black on silk and wool, with aniline, is much desirated. It is stated in some of our foreign exhanges, that J. Lightfoot, of Acrington, England, has produced such a black dye, but the partionlars of the procss have bot been published in full. It is only stated, that a salt of aniline is mixed with certain oxides (probably the oxides of iron) as a mordant.