76 QUESTIONS AND ANSWERS 



4. Applying centrifugal force to separate the 

 serum, the casein, and the chloroform fat solution. 



What pieces of apparatus are used in the Hart 

 casein test? 



1. A 5 c. c. pipette for measuring the milk. 



2. A cylinder holding 2 c. c. to the mark, for 

 measuring the chloroform. 



3. A strong test tube 5.6 inches long. About 

 2.6 inches of one end is formed into a graduated 

 neck one-half the diameter of the remainder, which 

 forms the body. The body of the tube should hold 

 35 c. c. and the graduated part exactly 5 c. c. Each 

 graduation on the scale represents .1 of i c. c, or .2 

 per cent of casein. The opening is at the large end 

 of the tube. 



4. A strong centrifuge properly constructed for 

 holding the test tubes and geared to give a speed 

 nearly twice as great as would be required in a 

 Babcock fat test machine having a revolving disk 

 of the same size. 



5. A thermometer for determining the tempera- 

 ture of the milk and acid solution. 



What reagents are used in the Hart casein test? 



Dilute acetic acid and chloroform of the best 

 quality. 



How much and of what strength is the acetic acid 

 used in the Hart casein test? 

 Use 20 c. c. of a solution containing 0.25 per cent 

 of acetic acid. 



