200 AN AGRICULTURAL WAR PROBLEM 



were so dear that to use them precluded all chance 

 of profitable beef production. Ground-nut cake 

 was far the cheapest food on the market suitable 

 for the purpose. But ground-nut cake has too 

 narrow a nutritive ratio, 1 : 0-8, to replace linseed 

 and cotton cake without the addition of something 

 to dilute its too high protein content. All foods rich 

 in carbohydrates with wide nutritive ratios were 

 extremely dear to buy, but swede turnips were 

 plentiful, and being home grown might be con- 

 sidered cheap. They contain a large proportion 

 of carbohydrate and practically no protein, so 

 farmers were recommended to use ground-nut cake 

 and to dilute its excess of protein by increasing the 

 ration of swedes. In order to assess the ration the 

 following procedure was adopted. Table I shows 

 that 4 Ib. of a mixture of linseed and cotton cakes 

 contains -84 Ib. of digestible protein and 2-32 Ib. of 

 starch equivalent. As swedes contain practically 

 no protein, it will be necessary to give all the pro- 

 tein in the form of ground-nut cake. Reference 

 to Table I once more shows that 2 Ib. of ground- 

 nut cake contains -90 Ib. of digestible protein, which 

 is near enough to -84 Ib. The starch equivalent of 

 2 Ib. of ground-nut cake is 1*55 Ib. This leaves 

 2-32 minus 1*55, i.e. 'JJ Ib. of starch equivalent to 

 be supplied by the addition of swede turnips. Since 

 the starch equivalent of 100 Ib. of swede turnips 

 is 7 Ib., the weight required to supply -77 Ib. of 

 starch equivalent is II Ib. of swede turnips. The 



