162 AMERICAN DAIRYING. 



with the test he can find out the difficulty him- 

 self. Investigate for yourselves. Find a reason 

 for occasional poor separations of the fat, if 

 you have them. You can find a remedy your- 

 self just as well as by applying to Dr. Babcock. 



A frequent difficulty. The inquiries con- 

 tained in some of the dairy papers seem to in- 

 dicate that black or white stuff separating with 

 the fat is the difficulty most frequently met 

 with. This makes an obscure reading of the 

 per cent of fat because of the indistinct separa- 

 tion of the liquids. The common remedy sug- 

 gested for this difficulty has been a change of 

 acid. If there is "black stuff" in the fat get a 

 weaker acid; if a white curd separates in the 

 fat column change to a stronger acid. That a 

 too strong or a too weak acid may cause this 

 trouble is undoubtedly correct in many cases, 

 but not always. The manipulations of the test 

 may also cause these defects. 



Points to be watched. My experience with 

 the Babcock test has taught me to follow the 

 directions given by the originator of the method, 

 and in doing so to keep a watchful eye on the 

 following points: 



1. Mixing and temperature of the milk. 



2. Strength, temperature, and quantity of the 

 acid. 



3. The way of pouring the acid into the milk 

 in the test bottle. 



