CHAPTER II.

Ammoniacal Liquor of Gas-works, 64. Origin of the Ammonia, 65. Ammonia as a Fertilizer, 65. Other uses of Ammonia, 67. Annual production of Ammonia, 68. Utilization of Coal-tar, 69. The Creosoting of Timber, 70. Early uses of the Light Tar Oils, 71. Discovery of Benzene by Faraday; isolation from Tar Oil by Hofmann and Mansfield, 73. Discovery of Mauve by Perkin, 74. History of Aniline, 75. The Distillation of Coal-tar, 77. Separation of the Hydrocarbons of the Benzene Series, 82. Manufacture of Aniline and Toluidine, 87. History and Manufacture of Magenta, 89. Blue, Violet, and Green Dyes from Magenta, 92. The Triphenylmethane Group, 97. The Azines, 108. Lauth's Violet and Methylene Blue, 111. Aniline Black, 114. Introduction of Azo-dyes, 115. Aniline Yellow, Manchester Brown, and Chrysoidine, 118. The Indulines, 121. Chronological Summary, 122.