ACIDUM OXALICUM — OXALIC ACID 369 



dom. It occurs either free or in combination with, potassium, cal- 

 cium or magnesium. It is present in large amounts in all acid fruits 

 and usually occurs with malonic, tartaric or other organic acids. It 

 is prepared by allowing lemon juice to ferment during which process 

 the gummy matter is precipitated. The proteids arc removed by 

 boiling and the filtered juice treated with chalk, forming calciimi 

 citrate. This is then decomposed by sulphuric acid and the citric 

 acid separated by crystallization. It is soluble in 0.54 of water, in 

 1.55 of alcohol. It is not used except as the vegetable salts of the 

 alkalies. 



ACIDUM TART ARICUM — TARTARIC ACID 



This is a dibasic organic acid usually obtained from wine lees or 

 argol. It occurs as colorless translucent, monoclinic prisms, or as 

 a white granular or fine powder; odorless, having an acid taste; 

 permanent in dry air. Soluble in 0.75 part of water and 3.3 of 

 alcohol. 



It is not used in veterinary medicine. 



ACIDUM TRICHLORACETICUM 



Trichloracetic acid is prepared through the oxidation of chloral. 

 It occurs as colorless, deliquescent, rhombohedral crystals, of a 

 slightly characteristic odor. It is soluble in water, alcohol and ether. 

 It is used as a caustic for warts. Is less painful than nitric acid. 



ACIDUM LACTICUM — LACTIC ACID 



Lactic Acid is prepared by subjecting invert sugar to lactic fer- 

 mentation in the presence of zinc oxide. The zinc lactate so formed 

 is then decomposed by hydrogen sulphide, and the filtered solution 

 evaporated to the desired amount. It occurs as a syrupy, colorless, 

 odorless liquid with an intensely acid taste. It is miscible with al- 

 cohol, water or ether. Externally, it is a caustic. It has no in- 

 ternal indications. 



ACIDUM OXALICUM — OXALIC ACID 



Oxalic Acid is prepared by the action of nitric acid upon sugar 

 or starch or by fusing sawdust with a mixture of sodium and potas- 

 sium hydroxides. It is purified by recrystallization. It occurs as 

 small colorless crystals, soluble in 10 parts of water, 2.5 parts of 

 alcohol. 



Uses. Oxalic acid is a caustic but is not often used on account 

 of its dangerous action following absorption. It has little real value 

 in medicine but may be used to remove stains of potassium perman- 

 ganate. 



