FACTORS INFLVENCINO MILK PRODUCTION 



307 



Figure 130. — Hand milk test- 

 ing machine. Reproduced 

 from Burrell & Co. catalog. 



that it is always kept in good repair 

 and in a sanitary condition. 



The testing of milk for its fat 

 jMHwaiH^^I^ content is in practical application 



e^BRl'pl'B flSWlll^^ daily in thousands of creameries 

 ■^^3iZ3lBtJ^B and on dairy farms. The Babcock 

 test, the invention of Dr. S. M. Bab- 

 cock, of Wisconsin University, is the 

 one in almost universal use, and is 

 made as follows. A fair sample of 

 milk is taken, in which the fat is 



well distributed. For example, if it is desired to test the milk 



of a cow, after it is drawn it is poured from one pail into 



another and then back again, to see that it is well mixed. 



Then with a glass pipette, 17.6 cubic centimeters of milk 



are measured, and this sample is placed in a small test 



bottle with a slender neck 



which is graduated up to ten 



per cent. Next 17.5 cubic 



centimeters of commercial sul- 

 phuric acid, having a specific 



gravity of 1.82, are measured 



off in a glass graduate, and this 



is poured into the bottle and 



mixed with the sample of milk. 



It is best to hold the neck of 



the bottle in a slanting position 



when pouring in the acid, 



turning the bottle during the 



operation, so that any milk 



which may have adhered to 



the neck will be washed down. 



This combination is attended 



with some heat, the contents ^'ment ^ i^ipette 



of the bottle turn a blackish Lrrdf & cT^atat^"''""^ '"" 



testing equip- 

 2 — milk bottle; 



