174 WHEAT. 



are given above, by means of washing, is how^ever far from being 

 very accurate ; it is impossible to prevent the loss of some gluten 

 which passes with the starch, and the vegetable albumen is entirely 

 lost by reason of its solubility in water : and then to dry gluten is a 

 very long and delicate process ; and if we would pretend to any de- 

 gree of accuracy, we must ascertain the quantity of fatty matter 

 contained in the samples. I therefore thought that with reference 

 to the azotized principles particularly, the better way would be by 

 proceeding to ascertain these by immediate ultimate analysis. 



The four azotized principles which we have already admitted 

 have very nearly the same elementary composition ; the mean propor- 

 tion of azote in each is 0.16. With this datum, it is evident that if a 

 particular sample of flour is found to contain 0.04 of azote, it may be 

 inferred that this azote represents 0.25 of gluten, albumen, fibrine, 

 and caseine, dried at 140° C. (284° F.,) and as these are the most 

 valuable elements in flour, I took the pains to ascertain their pro- 

 portion in a considerable number of vaHeties of wheat, the whole of 

 which were grown in the same year, in the same soil, which was 

 well manured, and under climatic influences that were identical ; nor 

 did I restrict myself to the azotized matters of these samples ; I also 

 endeavored to ascertain the precise relative quantities of bran and 

 of flour. The following table contains the results of my experi- 

 ments. 



