Inaccurate Standards of Valuation 279 



effect of a given ration too dependent upon variable 

 conditions, to allow logical conclusions from such ex- 

 perimental data. The difficulties of the situation 

 will be made clear to any one by a careful study 

 of the whole mass of data resulting from feeding 

 tests. Differences appear, some of which are consist- 

 ently in one direction, especially in comparing nitrog- 

 enous with carbohydrate foods, but as between mate- 

 rials of the same class their comparative values as 

 indicated by different experiments are greatly variable, 

 even contradictory. Any one who endeavors to reach 

 fixed and universal valuations on an experimental 

 basis of this kind will find himself involved in hope- 

 less confusion. 



Once in a while some one talks wildly about leaving 

 food valuation to the "old cow." It is sometimes con- 

 sidered a telling argument against the chemist's wis- 

 dom to declare that he and the old cow do not agree. 

 Certainly the cow knows better than the chemist what 

 she likes to eat, and it is little use to offer her foods 

 she does not relish. Even a chemist knows that. If, 

 however, a dozen commercial feeding stuffs were spread 

 around on a barn floor it would be much safer to 

 trust an agricultural chemist, especially one experi- 

 enced in stock feeding, to select a ration than any 

 cow ever grown, Holstein, Ayrshire, Jersey, long- 

 horned, dishorned, or what not. The cow would prob- 

 ably get at the corn meal and stay with it until well on 

 the way to a fatal case of indigestibility. Her judg- 

 ment is just about as good as that of a child with a 

 highly cultivated "sweet tooth." 



