THE EARTH'S BOUNTY, 



been in the habit of keeping market and 

 butter records, so that he can show the busi- 

 ness qualities, as well as the pedigrees, of his 

 animals. 



To intelligently use any of the tests for 

 estimating a cow's butter value, some knowl- 

 edge of the constituents of milk is necessary. 

 Professor Pearson describes milk as a whitish, 

 opaque liquid. To the ordinary observer it 

 appears to be a perfect solution, and is com- 

 monly regarded as such, being bought arid 

 sold by liquid measure; but, when placed 

 under the microscope, it is seen to consist of 

 a clear, transparent fluid, containing many 

 minute globules of various sizes. The fluid 

 part, called the milk serum, consists of water, 

 and all the other constituents of milk, except 

 the fat; and these other constituents, although 

 solids, when separated and dry, are mostly all 

 dissolved in the water, but part of them is in 

 a state of fine suspension or partial solution. 

 The globules are little bodies of pure fat scat- 

 tered through the serum and not dissolved. 



175 



