202 



CLEAN MILK 



false premise that pure milk has a precise, uniform specific gravity 

 and that it is possible — as it were — to measure nature with a yard 

 stick. Thus the readings under ioo are supposed to indicate the 

 amount of water added to milk. If, for instance, the reading were 

 95, it would mean that the milk was 95 per cent, pure and that it 

 was adulterated with 5 per cent, of water. 



Since pure milk varies considerably in specific gravity within 

 normal limits the fallacy of this scale is apparent. 



It would not receive so much attention here were it not in 

 common use in many of the Eastern states. To convert the read- 

 ings of the New York Board of Health lactometer into correspond- 

 ing readings of the Quevenne scale they must be multiplied by 0.29. 



QUEVENNE LACTOMETER DEGREES CORRESPONDING TO NEW YORK BOARD 

 OF HEALTH LACTOMETER DEGREES.* 



Curd Test. — This is a good rough and ready way to distinguish 

 clean from dirty milk. Liquid rennet is added to warm milk in a 

 milk bottle and when the curd has formed the whey is poured off. 

 'After the curd has formed a compact mass in the bottom of the 

 Jjar it should be cut open. In dirty milk the curd is riddled with 

 holes like a sponge owing to the development of gas caused by the 



* Jensen's Milk Hygiene. 



