CHAPTER XVIII. 



THE BABCOCK TEST. 



This is a cheap and simple device for determining the 

 percentage of fat in milk, cream, skim-milk, buttermilk, 

 whey, and cheese. It was invented in 1890 by Dr. S. M. 

 Babcock, of the Wisconsin Agricultural Experiment Sta- 

 tion, and ranks among the leading agricultural inventions 

 of modern times. The chief uses of the Babcock test may 

 be mentioned as follows : 



1. It has made possible the payment for milk accord- 

 ing to its quality. 



2. It has enabled butter and cheese makers to detect 

 undue losses in the process of manufacture. 



3. It has made possible the grading up of dairy herds 

 by locating the poor cows. 



4. It has, in a large measure, done away with the prac- 

 tice of watering and skimming milk. 



Principle of the Babcock Test. The separation of 

 the butter fat from milk with the Babcock test is made 

 possible : 



1. By the difference between the specific gravity of 

 butter fat and milk serum. 



2. By the centrifugal force generated in the tester. 



3. By burning the solids not fat with a strong acid. 

 Sample for a Test. Whatever the sample to be tested, 



always eighteen grams are used for a test. In testing 

 cream and cheese, the sample is weighed. For testing 

 milk, skim-milk, buttermilk, and whey, weighing requires 



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