381 DOMESTIC ECONOMY. [Chap. IV. 



tion for bis purposes, which arc of far less iini)ortancc than its cmploj-mcnt 

 in diet. While common hydrocliloric acid sells for tlirce cents per pound 

 ■wholesale, the purified article is sold for thirty-five. Tartaric acid is apt 

 to contain lime, and is frequently adulterated with cream of tartar, which is 

 sold at half the price, and greatly reduces its eilicacy ; while cream of tartar 

 is variously mixed with alum, chalk, bisulphate of potash, tartrate of lime, and 

 even sand. Sesquicarbonatc of ammonia is liable by exposure to the air to 

 lose a portion of its ammonia. It is hence seen that the substances wo 

 employ arc not only liable to injure by ingredients which they may con- 

 ceal, but that their irregular composition must often, more or less, defeat the 

 end for which they are intended. "We may suggest that in the absence of 

 tests, the best practical defense is to purchase these materials of the drng^ 

 gist rather than the grocer. If soda is desired, call for the bicarbonate of 

 soda ; it contains a double charge of carbonic acid, and is purest. Soda- 

 saleratus is only the crude, impure carbonate — soda ash. The cream of tartar 

 should appear white and pure, and not of a yellowisli tinge. Carbonate of 

 potash in its crude state appears as pearlash ; in its more jnirified form it is 

 saleratus. Crude soda is known as sal-soda or soda-saleratus ; refined and 

 cleared of its chief impurities, it forms carbonate and bicarbonate of soda. 

 All these compounds have the common alkaline or burning property, which 

 belongs to free potash and soda, which is lowered or weakened by the car- 

 bonic acid united with them. The potash compounds are the strongest, 

 those of soda being of the same nature, but Mxaker. Yet the system, as we 

 have just seen, recognizes essential ditierenccs between them ; one jxn-taiiis 

 to the blood and the other to the flesh. According to the theory of tlieir 

 general use for raising bread, they ought to be neutralized by an acid, mu- 

 riatic, tartaric, acetic, or lactic, thus losing their peculiar properties and be- 

 coming salts. These changes do take place to a certain extent, and the sa- 

 line compounds formed are much less powerful and noxious than the un- 

 neutralized alkalies ; their effects are moderately laxative. Yet, in the 

 common use of these substances, as we have stated, the alkali is not all ex- 

 tinguished ; much of it enters the system in its active form. Pure, strong 

 potash is a powerful corrosive poison, disorganizing the stomach and dis- 

 solving its way through its coats quicker, perhaps, than any other poisonous 

 agent. When the alkalies are taken in small quantities, as when there 

 is an excess in bread, they disturb healthy digestion in the stomach by neu- 

 tralizing its necessary acids. They are sometimes found agreeable as jial- 

 liatives when there is undue acidity of the stomach ; and, on the other 

 hand, they may be of service in the digestion and absorption of fatty sub- 

 stances. It is alleged that their continued use tends to reduce the propor- 

 tion of fibrin in the blood. Cases are stated where families have been poi- 

 soned by the excessive employment of saleratus." 



402. Baking Bread— Heat of the Oven— Quality of FIouFo— Tlie heat of the 

 oven, besides being equally diffused, should continue regular. The heat is 

 right when flour sprinkled on the oven-bottom turns brown gradually, and 



