1 82 AN AGRICULTURAL WAR PROBLEM 



with the feeding-stuff market that the list includes 

 only those feeding stuffs which are made of one 

 article, all compound feeding stuffs being omitted. 

 This perhaps requires a word of explanation. The 

 reason is that feeding stuffs made from only one 

 article have a more or less standard composition 

 which never differs widely from the average. It 

 is therefore possible to give their average composi- 

 tion with a fair measure of certainty, so that any 

 sample which a farmer may buy will not differ 

 appreciably from the figures given. But com- 

 pound feeding stuffs are made of a mixture of 

 various articles in varying proportions, both the 

 constituents and the proportions in which they are 

 mixed varying according to the markets. The 

 only constant property they possess is the pre- 

 sence of some condimental ingredient which is in- 

 corporated in order to produce a scent and flavour 

 which makes them palatable. They are not likely 

 to possess a reasonably constant composition or 

 digestibility and it is therefore impossible to state 

 their average content of digestible nutrients with 

 any degree of certainty so that the figures would 

 correctly represent the samples on the market. 



Before the figures in the table can be used as 

 a guide for buying it is necessary to reduce them 

 to one denomination. In the case of fat, carbo- 

 hydrates, and fibre, this is readily done, for di- 

 gestible carbohydrates and digestible fibre are equi- 

 valent to one another, and I Ib. of digestible fat 



