82 



MODERN METHODS OF TESTING MILK 



Enough water is added to bring the fat-column into 

 the middle of the small neck. In mixing milk and 

 acid and in running in hot water, care must be taken 

 to prevent any liquid but fat going into the small neck 

 or fine measuring-tube. The stoppers in the bottles 



FIG. 34 FIG. 35 



BOTTLES FOR TESTING SKIM-MILK 



are used to adjust the fat-column for reading. These 

 double-necked bottles should be placed in the tester 

 in such a way that the filling-tube is toward the center, 

 thus avoiding the danger of having any fat caught 

 between this tube and the side of the bottle when re- 

 suming the upright position after whirling. 



Separating fat from mixture in bottle. Attention 

 has previously (p. 64) been called to the difficulty ex- 

 perienced in separating all the fat from the mixture 



