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CHEMISTRY OF FARM PRACTICE 



is used in proportions of from 1 part formalin, 20,000 parts 

 milk or to 50,000 parts milk, the smaller quantity will 

 preserve milk for two days. Sodium carbonate ( 





T 



and magnesium carbonate (MgCOa) serve to neutralize 

 acidity and to improve the appearance of the milk. Potas- 

 sium carbonate (K^COs), borax (Na2B4O?) and boracic add 

 are used as preservatives. They tend, however, 



