4 ACIDS. 



In short, whenever any important fact offers itself, let it 

 be put down under some general head, making an index at 

 the end of the book of each head, and the number of the 

 page on which each subject is placed. This is the only safe 

 way of being sure of your facts. Medical men know this ; 

 and after listening to statements at college meetings, they 

 inquire of the speaker, Did you at the time make an entry 

 of these things in writing ? If the reply is in the negative, 

 they refuse to accept the matter, whatever it may be, as 

 reliable data. 



ACIDS. Liquids and substances which have a sharp 

 taste, and the property of changing vegetable blues to red. 

 This word is now used by chemists for a substance which 

 has not these properties, but has the capability of combining 

 with, and neutralizing, alkalies, various earths, and metallic 

 oxides, and in these forms is called salts. 



In most plants we find vegetable acids. 



Tartaric Acid is discovered in grapes, tamarinds, white 

 mulberries, dandelions, &c., &c. 



Citric Acid exists in lemons, oranges, whortleberry, the 

 onion, &c., &c. 



Malic Acid is the only acid detected in the apple ; - it is 

 found also in the barberry and the plum, and some other 

 fruits. The gooseberry, currant, cherry, strawberry, rasp- 

 berry, admit it with citric acid. Combined with lime, it is 

 found in the houseleek and other plants ; with both lime and 

 potash, in spinach, rue, mignonette, and many other plants. 



Benzoic Acid is in benzoin, the medicinal resin imported 

 from the East Indies ; also in the balsam which is extracted 

 from a South American tree called Tolu, in storax, in an 

 herb of the sage genus, called Clary, in chickpea, &c., &c. 



Oxalic Acid is found in many common plants ; in wood- 

 sorrel, combined with potash ; united with lime, it is detected 



