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tibly destroy any butter fat, but the card and whey 

 separate, and this mechanical condition of the milk 

 makes it impossible to take out a small quantity which 

 will fairly represent the whole. 



Sour milk can be put into proper condition for testing 

 by adding to it an alkali which will neutralize the acid 

 developed and dissolve the curd. The "powdered lye," 

 sold by nearly all grocers for making soap, can be used 

 for this purpose with good success. By stirring one-half 

 a teaspoonful of this caustic alkali into a pint of sour 

 milk, the separated lamps of curd are soon dissolved and 

 the sour milk becomes as thin and homogeneous as new 

 milk, so there is no difficulty in testing it. 



To demonstrate the accuracy of this method of 

 diminishing the number of tests by collecting a com- 

 posite sample of milk and the' practical use of the 

 " powdered lye " on sour milk, I made the following 

 experiment at a creamery. 



Twenty patrons were selected and among them were 

 included those who brought milk that varied most from 

 day to day in quantity and quality. As the milk 

 brought by each of these patrons was poured into the 

 large weighing can at the creamery, it was thoroughly 

 mixed and about a pint taken out for the experiment. 

 A test was made of this milk every day and a portion 

 of it put into each of three-quart glass fruit-jars 

 labeled respectively A, B and C. The jars of series A 

 and B contained the poison corrosive sublimate, the 

 jars C nothing but the milk which soon soured, as the 

 temperature of the room where they were kept ranged 

 from 60 deg. to 85 deg. F. The quantity of milk added 

 to jars of series A and C was the same each day, about 

 one-twentieth of a quart, one dipper being used for 

 measuring the milk in these two series. The amount 



