COMPOSITION OF WHEAT FLOUR 269 



In a paper published in 1857 they gave the results of a 

 series of experimental millings of wheat grain from three of the 

 plots the unmanured plot, that which receives nitrogen only in 

 the shape of ammonium-salts, and one that is completely 

 manured with both minerals and ammonium-salts. The grind- 

 ing was done by an ordinary millstone, then the only method 

 of grinding wheat. Figures were obtained showing the relative 

 weights of the nine mill products flour of various grades of 

 fineness, tails, sharps, pollard, and bran figures which 

 are unfortunately of little interest nowadays since the roller- 

 milling which has become universal has introduced quite a 

 different series of separations. Holler- milling, also, no longer 

 bruises the bran in the way that was inevitable with stone 

 grinding, so that the composition even of the finest products 

 has been to some extent altered. Further determinations were 

 then made of the dry matter, ash, nitrogen, and phosphoric acid 

 in the various products, as had previously been done for several 

 seasons with the whole grain. The results showed that the 

 percentage of nitrogen was lowest in the products at the head 

 of the dressing-machine, i.e., in the flour itself, but increased 

 considerably in the more branny portions, being at its highest 

 in the sixth product, the so-called " coarse sharps." The ash 

 increased to a still greater degree in the coarser portions, being 

 ten times as great in the coarsest bran as in the finest flour, and 

 the percentage of phosphoric acid augmented with the increase 

 in the percentage of ash. 



But Lawes and Gilbert protested most strongly against the 

 idea which was then beginning to be held, and which has never 

 ceased to be promulgated as a sort of creed that the whole 

 meal of the wheat grain is the most nutritive food, and that 

 ordinary white bread is deprived of much of its value because of 

 the removal of the bran. 



For example, Gilbert wrote in 1881 : " The higher per- 

 centage of nitrogen in bran than in fine flour has frequently 

 led to the recommendation of the coarser breads as more 

 nutritious than the finer. We have already seen that the 



