Prep. By dissolving half an ounce of acetate of soda (Na 0, C4 H3 O3 + 6HO), in five fluid ounces of distilled water.

Use. It is directed to be added in excess to the solution of phosphate of lime in nitric acid, previous to the addition of oxalate of ammonia and perchloride of iron; the nitric acid is thus neutralized, and the oxalate of lime and phosphate of iron are insoluble in the acetic acid, which is then set free.