THE EARTH'S BOUNTY 



vary from 12 to 13 per cent., according to 

 different laws; which means, of course, that 

 in every 100 pounds of milk there shall be 12 

 or 13 pounds of solid matter. These legal 

 requirements are justified by the fact that it 

 is the solid matter, and not the water, which 

 gives value to milk. 



The fact that the standard so often relates 

 to the proportion, or percentage, of fat, and 

 the popular impression that the milk is with- 

 out value after the cream has been removed, 

 lead some people to think that fat is the only 

 valuable part of milk. This is a great error. 

 The several other constituents are valuable; 

 for example, casein is one of the cheapest 

 forms of nitrogenous food, and is more nu- 

 tritious than similar compounds in many other 

 , foods, It is, of course, safe to judge of the 

 quality and value of milk by the fat it con- 

 tains, because, if milk is poor, from either 

 natural or unnatural causes, the quantity of 

 fat will be affected at least as much, and 

 oftentimes more, than any other constituent. 



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