Baking-Powder
Baking-powder is a mixture of cream of tartar, bicarbonate of soda, and arrowroot. The latter is used to keep the two chemicals dry, and thus prevent the slow union which would otherwise take place. Sometimes tartaric acid is used instead of cream of tartar. The following rule may be relied upon:
| Tartaric acid | 2 oz. by weight. |
| Bicarbonate of soda | 3 ″ ″ ″ |
| Arrowroot | 3 ″ ″ ″ |
Mix and sift together thoroughly. Keep in a dry place, in a wide-mouthed bottle.