5O MODERN METHODS OF TESTING MILK 



film and the wall should be clear and bright. This 

 can be accomplished without serious trouble. 



As soon as a test is completed and the amount of 

 fat read, the test-bottle, while still 

 warm, should be emptied. This 

 may easily be done by having a 

 large earthenware jar or crock, 

 covered with a board (Fig. 22), 

 in which are several holes large 

 enough to admit easily the necks 

 of test-bottles. The bottle is in- 

 verted, the neck run down through 

 one of these holes, and at the 

 same time the bottle is shaken up and down in 

 order to remove the white calcium sulphate de- 

 posited on the bottom of the bottle during the test. 

 Then, when one is ready to clean up all the bottles 

 that have been used, each one is rinsed with 8 or 10 



FIG. 22 WASTE-JAR 

 FOR EMPTYING 

 TEST-BOTTLES 



FIG. 23 TEST-BOTTLE U1NSEE 



