ON MILK AND MILK-TESTING 97 



acetate reagent, and a stand to support the appa- 

 ratus. 



A representative lo-gram sample of butter is 

 placed in the metal cup. To this is added 10 c. c. 

 of the amyl acetate reagent. The apparatus is 

 then connected and the condenser filled with cold 

 water. The alcohol flame is then applied under 

 the evaporating cup. In about a minute the water 

 and reagent will begin to pass over and drop from 

 the condenser tube into the receiver. After all the 

 water has been evaporated from the cup, the reagent 

 will cease dropping for a moment and then begin 

 again as soon as it has reached its own boiling 

 point, which is higher than that of the water. Con- 

 tinue to apply the flame until practically all the re- 

 agent is driven oif and it ceases to drop freely from 

 the condenser tube. By this means all the water 

 is washed out of the condenser tube and the major 

 portion of the reagent is recovered. The flame is 

 now extinguished. The mouth of the receiver is 

 corked and taken by the top and shaken a few 

 times to detach any drops of water that may 

 adhere to the sides. 



The per cent moisture can now be read in the 

 graduated receiver. The water is withdrawn from 

 the receiver, and then the reagent, which is collected 

 in a bottle and preserved for use in later tests. 



