182 AGRICULTURE. 



milk pipette may be used and the testing carried 

 out the same as with milk, except only about 

 three-fourths the usual amount of acid is used. 



If the cream has more than 30 per cent, of 

 fat it cannot be read on the scale on the bottle. 

 U nder these circumstances one measure of cream 

 and one of water may be mixed together, and a 

 test made of the mixture, doubling the readings. 



Weigh Out Cream for Testing. The fore- 

 going methods of testing cream are accurate 

 enough for some purposes, but when cream is 

 bought and sold by the per cent, of butter fat 

 the amount of cream taken as a sample for test- 

 ing should be weighed out and not measured. 

 The measuring of cream introduces several 

 errors which cannot be discussed in detail here, 

 but all tend to make the result of the test too 

 small. The chief error affecting accuracy of 

 measuring cream is the difference in specific 

 gravity of cream and milk. The i 7.6 c. c. pipette 

 delivers 18 grams of milk, but as cream is lighter 

 than milk, does not deliver 18 grams of cream. 



To avoid all these errors, small balancers are 

 used, and 18 grams of cream weighed out into 

 the test-bottle. 



. CREAM. 



I. Separation of Cream. 



Cream is that portion of milk into which most 

 of the fat globules have been gathered. It has 

 the same constituents as milk, but in a different 



