The simplest kind of saline is made by mixing together 1 oz. of tartaric acid and 1 oz. of bicarbonate of soda. If required sweetened, mix with 2 oz. of finely powdered sugar. All the powders should be thoroughly dried before mixing. Seidlitz powders are very useful salines. The powder in the blue paper contains 2 drachms of Rochelle salt and 2 scruples of bicarbonate of soda. The powder in the white paper contains 1/2 drachm of tartaric acid.