234 DOMESTIC ANIMALS, DAIRYING, ETC. 



if, by running the separator too slowly or separating the milk when 

 too cold or for other reasons, the skim milk should contain .15 per 

 cent or more of fat, the loss may amount to $1 or $2 per cow per year. 

 This amount of money will more than pay for the entire expense of 

 installing and operating a Babcock test. Although the fat in the 

 skim milk is not wasted when fed to pigs or calves, yet it is much 

 more profitable to sell butter fat as cream or butter than it is to make 

 veal or pork out of it. 



The three important uses for the Babcock test on the farm are : 

 First, cow testing, regularly done, in order to improve the herd; 

 second, frequent testing milk or cream before it is sold, to determine 

 if the testing done at the factory is correct ; third, occasional testing 

 of skim milk, to see that no butter fat is being wasted. 



The Babock test is saving many times its cost annually on many 

 dairy farms, and at the same time is enabling farmers to select their 

 best cows and to improve their herds more rapidly than can be done 

 by any other means. There should be a Babcock tester regularly 

 used, on every dairy farm. 



Material Needed. The materials and apparatus used on the 

 farm for testing milk are: (1) Milk scales; (2) weighing pail; (3) 

 bottle of preserving tablets; (4) bottle of sulphuric acid; (5) hand 

 Babcock tester; (6) milk test bottles; (7) acid cylinder; (9) pipette 

 (17.6 cc.) ; (10) thermometer; (11) record book. 



Steps in the Babcock Test. (1) Mix the milk thoroughly and 

 take out a small sample; (2) do not let the sample evaporate or 

 curdle before testing; (3) fill the 17.6 cc. pipette to the mark with 

 milk; (4) empty the pipette without loss into a Babcock test bottle; 

 (5) add sulphuric acid from the measuring cylinder to the test bottle; 

 (6) mix the acid and milk thoroughly by shaking the bottle; (7) 

 place bottles in the centrifuge, cover, and whirl 5 minutes; (8) add 

 hot mater and whirl again twice, one minute each time; (9) read 

 and record the per cent of fat in the neck of the test bottle; (10) 

 empty the test bottles and wash thoroughly. 



Mixing and Sampling Milk. Provide a quart or more of milk, 

 with which to practice sampling and testing. Mix it thoroughly by 

 pouring several times from one vessel to another, or by stirring vig- 

 orously. Larger quantities of milk require longer stirring. While 

 the milk is still in motion, dip out a half teacupful and pour this at 

 once into a small, clean, dry bottle. Fill the bottle nearly full, and 

 stopper tightly to prevent evaporation. Label the bottles with the 

 name of the cow or owner. 



The small sample of milk taken for the Babcock test must con- 

 tain exactly the same proportion of fat as the entire contents of the 

 pail or can. If milk stands quiet for even a few minutes, the cream 

 will begin to rise, and the top layer on the can will contain more fat 

 than the rest of the milk. If the top part is used for the test, it will 

 indicate a higher per cent of fat than is present in the entire lot of 

 milk. It is incorrect to take a sample out of a pail, can or vat of 

 milk for testing without first thoroughly mixing the milk by stirring, 

 or pouring it from one vessel to another. 



