SECT. XII. ACIDS. 417 



certain stage of fermentation, has been found also 

 ready formed in the sap of several trees as analysed 

 by Vauquelin ; and also in the acid juice of the 

 Cicer arietinum, of which it forms a constituent 

 part. It was obtained also by Scheele from the sap 

 of the Sambucus nigra ; and is consequently to be 

 regarded as a native vegetable acid. It is dis- 

 tinguished from other vegetable acids by its form- 

 ing soluble salts with the alkalies and earths. 



SUBSECTION in. 



Citric Acid. Citric Acid is the acid that exists 

 in the juice of Lemons. Its taste is very sour in a 

 state of purity, but [exceedingly pleasant when 

 diluted with water. By a red heat it yields car- 

 bonic acid gas and carbonated hydrogene gas, and is 

 reduced to a charcoal : nitric acid converts it into 

 oxalic and acetic acid, and with lime it forms a salt 

 insoluble in water. 



It is much used in the state of Lemon-juice to 

 give a seasoning to liquors, which it does equally 

 well in its concentrated state also. It has been 

 found unmixed with other acids in the following 

 vegetable substances : jn the juice of Oranges and 

 Lemons, and in the berries of Vacclnium OxycocciiS) 

 Vitis Idceciy Prunus Padus, Solanum Dulcamara, 

 and Rosa canina. It has been found also in many 

 other fruits, mixed with other acids. 



VOL. j. 9, K 



