56 QUESTIONS AND ANSWERS 



If the fat has the proper color, but contains undis- 

 solved substance, what is the trouble? 



It usually indicates insufficient mixing before 

 placing in the centrifuge, but may possibly be due 

 to improper water. 



When should the per cent of fat be read? 



Immediately upon completing the whirling, if 

 the temperature of the fat is correct. The fat 

 solidifies at about 100° F., and the temperature of 

 the bottles should be considerably above that dur- 

 ing the whirling. 



How should the fat be measured? 



By holding the fat column on a level with the eye 

 and counting the diyisions on the scale in that part 

 of the neck occupied by the fat. Give credit 

 for all the fat between the lowest and highest points 

 on the fat column. Each division on the scale 

 usually represents two-tenths of i per cent, but 

 some bottles are now made upon which each divi- 

 sion represents one-tenth of i per cent. 



How may an instrument assist in measuring the 

 fat? 



By using some form of dividers and fixing the 

 points at the extreme ends of the fat column. Then 

 change the position until one point rests on the zero 

 mark and the other on the scale above. The inter- 

 vening space will have a length equal to that of the 

 fat column and the per cent may be read directly. 



Does all the fat rise in the neck of the bottle? 

 It has been found by comparing the results with 



