104; FEDERAL REPORTER. �vention consists in the use of the heavy oil of tar or dead oil, or crude carbolic acid, as it is sometimes called, or creosote, obtained in the destructive distillation of carbonaceous sub- stances. These materials I treat with an alkali, and add a saponifiable fatty substance. And, in order that my invention may be fully understood, I will proceed to describe a method by which I carry the same into practical operation. I take crude carbolic acid, or heavy oil of tar, or other products obtained from the distillation of tar, which, like those men- tioned, have a greater specifie gravity and a higher boiling point than water, and act upon it with causfcic soda or pot- ash, so as to render it soluble or mixable with water. This mixture is heated (say to about the boiling point of water) and agitated, so that all the parts may be equally acted upon. I then add to it fat, tallow, or other saponifiable substance, and give it the consistency of a soft paste, in which condition it is suitable for use. The proportions may be varied, but those I prefer are two parts by weight of the carbolic acid, one part by weight of caustic soda of 50 deg. Twaddle, and one part by weight of tallow, fat, or other saponifiable sub- stance. The composition thus prepared, if not to be used for salving, may be dissolved in water and used in a bath, in which the sheep or other animais are to be dipped, or it may be used by 'pouring' or otherwise, as is well known tg those acquainted with the management of stock requiring such treatment." The claims are: "Firstly, the use of carbolic acid in the preparation of materials or compositions for de- stroying vermin on sheep and other animais, and for protect- ing them therefrom; secondly, the use of alkalies and tallow, or other saponifiable substance, in combination with the above products, when used for the purposes above set forth." The proper interpretation of the McDougall specification seems to be that he speaks of two substances. One is the heavy oil of tar, which is also called dead oil and is some- times called crude carbolic acid. The other is creosote, ob- tained in the destructive distillation of carbonaceous sub- stances. He uses an alkali, such as caustic soda or potash. He also uses saponifiable fat or saponifiable tallow, or other ��� �
