of the University of Pennsylvania. 45 



I. " Nutritive salts" (Niihrsalze of Liebig). 

 II. Carbohydrates. 



III. Proteids, notably gluten. 



The facts, also, that branny foods in common 

 with many others will spur an atonic bowel to 

 activity, give due bulk to its contents, and induce 

 the passage of stools of the normal or feculent con- 

 sistency are noteworthy, but their further consider- 

 ation is beyond the limits of the present paper. 

 The other reasons for the retention of bran in wheat- 

 flour will be discussed seriatim. 



I. The fact that fine flour contains a much smaller 

 percentage of salts than does either bran or the whole 

 wheat a fact evidenced by the relatively small 

 amount of ash which it yields forms the basis of 

 the theory of Liebig, 1 that in the removal of bran 

 nutritive salts of value are lost. The investigations 

 of Meyer 2 and Forster 3 are often cited as showing 

 that after the removal of bran, these salts are still 

 present in quantity sufficient for the needs of the 

 economy. 



Our experiments upon young pigs, described fur- 

 ther on, show that although survival is quite pos- 



1 Chemische Briefe, 1851. 



2 Zeitschrift f. Biologie, vol. vii. p. 33. 



3 Ibid., vol. ix. pp. 293-380. 



