DITTMAR V. RIX. 345 �heating and treating it with concentrated sulphuric acid and chloride of calcium. It is now pressed through a fine sieve, and mixed with eitlier dried pulverized starch that- bas been treated with nitre lye, or it is mixed with cellulose prepared as above described, until a dry and not very greasy powder is obtained. b. After the starch has been dried it is mixed with pulverized cellulose, or with the dualin dust prepared by pro- cess No. 3. This mass is tlien placed in a mixture of nitrie acid (48° B.) and sulphuric acid, (66° B.,) and for the rest, treated as described by process No. 5. No. 6. In an entirely analogous manner, mannite is mixed with anhydrous glycer- ine and compounded with the other ingredients of dualin. I do not claim nitro-glycerine, nor mixtures of nitro-glycerine with other explosive or non-explosive materials, as such have been made, but they do not possess the properties of my com- pound." �There are two claims, as follows : "1. The process of man- ufacture or preparation of a oompound which I denominate ' dualin,' of the ingredients, in the proportions and for the purposes set forth. 2. Also the new compound, herein de- scribed, ealled dualin, made by the process herein set forth, or its chemieal equivalent." �The powder alleged to infringe the patent is one which, by an analysis shown by che plaintiiï, contains, in 100 parts by weight, the foUowing substances, in the following proportions : Nitro-glycerine, 36.78 per cent.; nitre, 47.45 per cent.; cel- lulose, 13.50 per cent. ; volatile matter, moisture, 212" Fahr., 2.27 per cent. It is claimed by the plaintiff that the nitre and the cellulose in such powder are the ingredients specific- ally mentioned in the plaintiff's patent, under process No. 1 therein, as to be mixed with nitro-glycerine, and that the resulting powder is a powder answering the description of said patent. The powder is one made and sold by the defend- ants as "Giant Powder No. 2." The defendants admit that they use, in making it, nitro-glycerine and nitre, the latter in the form of nitrate of potash or nitrate of soda, and a carbon or hydrocarbon, such as soft or hard coal, resin or wood fiber. They allege that the wood fiber is mostly common saw- ��� �
