1902-3] The Chemistry of Wheat Gluten. 501 



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GLUTEMN. 



1 1. — Observations. 



While working at the composition of wheat flour, Professor 

 Macallum suggested that 1 should trace to its source the phosphorus 

 which he found to be present in the cellular elements of the wheat 

 grain. It was sought for and found in gluten, no matter how carefully 

 prepared or how long it had been washed in tap or distilled water. 

 Gluten was prepared in the usual manner by kneading dough in a 

 stream of water until free from starch, dried at no C. until the weight 

 was constant and the phosphorus estimated according to Neumann's-^'' 

 method, which was found by experiment on known solutions of phos- 

 phoric acid to be perfectly accurate. Two quantities of gluten yielded 

 O. II and 0.12 per cent, of phosphorus respectively. 



In order to determine next which of the constituents of gluten {i.e., 

 gliadin or glutenin) contained phosphorus, gliadin was prepared by 



