RECEIVING, SAMPLING, AND GRADING. 85 
There are two tests commonly used for determining fat in 
milk, viz., the Babcock and Oil-test Churn. The latter method 
is rapidly giving way to the former. The Babcock test is un- 
doubtedly superior, though many still prefer the Oil-test. 
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Fic. 30.—17.6 ¢.c. milk Fic. 31—Automatic Fic. 32.—Automatie 
pipette. 17.6c.c. pipette. Russian pipette. 
The Babcock method of testing consists of taking 18 grams of 
the substance to be tested into a special graduated bottle as 
shown inillustration. Milk is measured out with a pipette hold- 
ing 17.6 c.c. Cream, butter, and cheese, or any other substance 
which cannot be measured accurately, should be weighed. 
‘The measured quantity of milk in the bottle is then digested by 
adding 17.5 c.c. of commercial sulphuric acid having a specific 
gravity of about 1.82. The acid digests all proteids and sets 
