The Babcock Test. 



73 



having been constructed for this 

 purpose. The machine gives satis- 

 factory results by the Babcock test 

 as well, provided the acid used is 

 1.83-1.84, or if the bottles contain- 

 ing the acid-milk mixture be placed 

 in hot water for five or ten minutes 

 prior to the whirling. As the bottles 

 are calibrated for only 5 cc. of milk 

 and the neck of the 

 bottles, with scale, is 

 correspondingly fine, 

 testing milk with this 

 machine requires some 

 nicety of manipula- 

 tion not called for in 

 case of regular Bab- 

 cock testers constructed 



FIG. 29. Physician's centri- for the use of farmers f^t tJhvsi- 



irQ +Ko+ 1^0 IT Via 11 ttrtsl tr\ ,' < I IT . V . J 



FIG. 30. 

 Test bottle 

 pipette 



fuge that may be used for milk 

 testing. 



and dairymen. 



clan's cen- 

 trifuge. 



Questions. 



1. Give a short description of the Babcock test. 



2. State precautions to be observed in each of the following 

 operations: (a) Measuring the milk, (b) adding the acid, (c) 

 whirling the bottles, (d) adding the water, (e) measuring the fat. 

 If the fat separates clear, but the results come evidently too 

 low, what is the probable cause, and how can the correct test be 

 established? 



3. To what extent does the temperature of the fat, when 

 read, influence the result? 



4. Explain the graduations of the milk test bottle. 



5. What is the capacity of the neck of a milk test bottle be- 

 tween the and 10 marks, expressed in cc., and in grams? 



6. If the graduations of a test bottle measure 2.3 cc. from 

 to 10%, what would be the correct test of a sample which reads 

 3.4% fat in this bottle? 



