Green, Scheele’s

This is arsenite of copper. Prep. 1. White arsenic (in powder), 1 part; commercial potash, 2 parts; boiling water, 35 parts; di olve, filter, and add the solution gradually, whilst still warm, to a filtered solution of sulphate of copper (cryst.), 2 parts, as long as a precipitate falls; lastly, wash the newly formed pigment with warm water, and dry it. 2. (Ure.) Powdered arsenious acid, 11 oz.; carbonate of pota a, 1 1 ⁄ 2 lb.; boiling water, 1 gall.; di olve, filter, and add the solution, as before, to another solution of crystallised sulphate of copper, 2 lbs., in water, 3 galls. Prod. 1 1 ⁄ 2 lb. A very fine gra -green colour.