224 FARMING ON FACTORY LINES 



which means passing through its body, unused, the 

 excessive amount of carbohydrates and fat. 



MEASURING FOOD VALUES 



Just as we can express the length of a wall in feet 

 and inches, the quantity of a liquid in pints, the weight 

 of a substance in lbs., etc., the heat of a substance in 

 degrees, so have we a unit to express the true values of 

 a food. This unit is known as the STARCH VALUE. 

 That is to say, scientists found just exactly what the 

 food value of a pound of starch was, and expressed all 

 food values in terms of starch. 



For instance, the starch value of linseed cake is 76, 

 which means that 100 lbs. of linseed cake for feeding 

 purposes — assuming it to be used in a properly 

 balanced ration — is equal to 76 lbs. of starch. In like 

 manner the starch value or equivalent of 7 lbs. of 

 meadow hay is 2.59, which means that this quantity 

 of vetch hay has the same feeding value approximately 

 as 2\ lbs. of starch. 



The starch value of foods in a manner which need 

 not be here described is calculated from the total 

 amounts of digestible albuminoids, fats, and carbo- 

 hydrates in a food, and hence enables us at once to see 

 the nutritive value of a food without referring to the 

 amounts of the particular food ingredients which the 

 food contains. 



THEORY AND PRACTICE — A SHORT CIRCUIT 



A study of the foregoing is useful in order to get a 

 thorough grip of the principles underlying the science 



