30 QUESTIONS AND ANSWERS 



To convert the board of health lactometer reading 

 to the Quevenne reading, multiply the board of 

 health reading by .29; and to convert the 

 Quevenne reading to board of health, divide the 

 Quevenne reading by .29. 



If a sample of milk read 108 on the board of health 

 lactometer at 66° F., what would its specific 

 gravity be at 60° F.? 



In this problem the temperature correction may 

 be made first, then convert to the Quevenne reading 

 by multiplying by .29, and finally prefix the figures 

 i.o. 



66—60=6. 6X.3=i.8. 



108+1.8=109.8. 



i09.8X.29=3i.84. 



The specific gravity, therefore, is 1.03 184. 



Between what graduations on the board of health 

 lactometer may normal milks vary? 

 Between 103 and 115 and in some few cases milk 

 may read as low as 100 or as high as 118. 



Between what graduations on the Quevenne lacto- 

 meter may normal milks vary? 

 Between 30 and 34, but in rare cases the milk may 

 read as low as 29 or as high as 35. 



Upon what law of physics does the action of the 

 lactometer depend? 

 It depends upon the fact that a solid body float- 

 ing in a liquid displaces a weight of the liquid 

 equaling the weight of the floating body. 



