FOOD VALUE OF DIFFERENT FLOURS 271 



perfect state of fineness, and it were found that this prevented 

 the aperient action, and that other evils were not induced, or 

 better still, if more of the food material can be separated from 

 the bran, and in either case without more cost than the saving 

 would be worth, there might be some advantage. But, to 

 suppose that whole wheat meal, as ordinarily prepared, is, as 

 has generally been assumed, weight for weight, more nutritious 

 than ordinary bread-flour, is an utter fallacy, founded on 

 theoretical text-book dicta : not only entirely unsupported by 

 experience, but inconsistent with it. In fact, it is just the 

 poorer fed and the harder working that should have the 

 ordinary flour bread rather than the whole-meal bread as 

 hitherto prepared, and it is the over-fed and the sedentary that 

 should have such whole-meal bread. Lastly, if the whole 

 grain were finely ground, it is by no means certain that the 

 percentage of really nutritive nitrogenous matters would be 

 higher than in ordinary bread-flour, and it is quite a question 

 whether the excess of earthy phosphates would not then be 

 injurious." 



The persistent idea that the branny portions of the grain 

 possess a higher nutritive value comes from trusting in the 

 crude chemical view of a century ago, that the percentage of 

 nitrogen alone measures the value of a food, without taking 

 any account of its digestibility and the amount of these 

 nitrogenous materials which can be assimilated by the body. 

 As to the extra value of the phosphoric acid, there is no 

 evidence to show that the ordinary dietaries are in any way 

 deficient in phosphates. The whole subject has, during the 

 last few years, been elaborately tested experimentally in the 

 course of the nutrition investigations of the United States 

 Department of Agriculture, with the result that Lawes and 

 Gilbert's opinion of the superior nutritive value of white bread 

 has been fully confirmed. 



The other question raised by Lawes and Gilbert in the 1857 

 paper, that of the effect of the different systems of manuring 

 upon the baking quality of the wheat and the differences in 



