MODERN METHODS OF TESTING MILK 



to about 17.5 cc. by adding water to 

 the cream and mixing before adding 

 acid. 



SPECIAL CREAM-TESTING 

 BOTTLES 



To test in one bottle an 1 8-gram 

 sample of cream containing over 10 

 per cent, of fat, the neck must be 

 made to hold more than the neck of 

 a milk-bottle, that is, more than 2 cc. 

 This additional space must be ob- 

 tained ( i ) by using a neck of larger 

 diameter, keeping the length the same 

 as in the milk-bottle or (2) by mak- 

 ing the neck longer, keeping the diam- 

 eter the same. There is this objection 

 to making the necks of test-bottles too 

 large in diameter, that the divisions 

 on the scale come nearer together 

 and the reading of the results is less 

 accurate. If the neck is made long 

 enough to allow as fine graduation 

 as in the milk-testing bottles, then 

 the bottles are too long to use in an 

 ordinary tester. 



Bulb-necked cream-bottle. Both 

 of the difficulties mentioned above are 

 overcome by having a bulb made in 

 the neck of the bottle (Fig. 29). In 

 this cream-testing bottle the gradua- 

 tion is as fine as in the milk-testing 

 bottles, the smallest division repre- 

 senting .2 per cent., and the scale ex- 



s 

 Ls 



fc 



/\ 



FIG. 29 

 BULB-NECKED 

 CREAM -BOTTLE 



