The Art of Perfumery, and Methods of Obtaining the Odors of Plants

Their specific gravities fluctuate between .91 and .93. When heated, fats assume a dark color, and boil between 482° and 572° Fahr., but the boiling-point continuously rises, while an uninterrupted decomposition proceeds. From oxide of glycyl ensues acroline; oleic acid affords a fatty acid, and among the decomposition products of fats containing stearine and margarine are found pure margaric acid, and, at the same time, some hydro-carbons are formed. When exposed quickly to a high temperature, fats are completely decomposed. (Oil gas.) In closed vessels the pure fats undergo no change, but, placed in thin layers in the air, the fats containing oleine and oline rapidly absorb oxygen under the strong evolution of heat, which will inflame porous bodies, as cotton wool. The purer the fats are the more quickly their oxidation results. When the fats contain slimy materials, these latter can be destroyed with a little oxide of lead and water. (Preparation for the application of varnishes.) The action of nitric acid, nitrous acid, chlorine, sulphuric acid, &c., on fats is the same as that of these bodies on the fatty acids. The fatty oils dissolve sulphur in the heat which is again partly precipitated on cooling. When sulphur is heated with fatty oils, namely, with linseed oil, it dissolves by degrees, and a thick dark mass is formed, the so-called balsam of sulphur. By raising the heat, a violent reaction ensues under the evolution of sulphuretted hydrogen, and, at the same time, an oil resembling oil of garlic volatilizes. This oil begins to boil at 160° Fahr., but its boiling-point rises continually.