40 THE CEREALS IN AMERICA 



what with the season, as docs the nitrog^en, on account of irreg- 

 ularities in the ripening of the seed, and only slightly on account 

 of different modes of manuring except in cases of abnormal soil 

 exhaustion. From three plats manured as indicated in the table 

 below, Lawes and Gilbert found the average annual yield of total 

 mineral constituents during sixteen years to be as follows : ' 



In Grain In Straw Total 



Lb. Lb. Lb. 



By farm yard manure . 36.3 20T.1 237.4 



Without manure . . 16.6 89.5 106. i 



With ammonium salts alone 23.0 119.2 142.2 



Where ammonium salts alone were used the grain showed 

 exhaustion both of potash and phosphoric acid — especially the 

 latter, while in the straw there was a marked deficiency of the 

 former. 



69. Protein. — In 310 analyses of American grown wheats 

 compiled to September ist, 1890, the protein (N x 6.25) varied 

 from 8.1 to 17.2 per cent, with an average of 11.9 per cent in 

 samples containing an average of 10.5 per cent water, or in 

 other words, the protein was 13.3 per cent of the dry matter of 

 the grain. Koenig reports the range in protein of the wheat 

 grain from various parts of the world to be from five to twenty- 

 four per cent, but that seventy-five per cent of all analyses fall 

 within eight to fourteen per cent. ^ 



The nitrogenous compounds of wheat consist principally, if 

 not wholly, of proteids, of which five have been recognized and 

 studied by Osborne and Voorhees as follows:^ (i) 2. globulin, 

 0.6-0.7 per cent of the grain; (2) an albumin, 0.3-0.4 per cent; 

 (3) a proteose, 0.2-0.4; (4) gliadin, 4.25 per cent; and (5) 

 glutenin, 4-4.5 per cent. (71, 72) 



1 Jour. Am. Chem. Soc. Vol. XLV (1888), p. 20. 

 a U. S. Dept. of Agr., Div. of Chem. Bui. 4, p. 69. 



8 The Proteids of the Wheat Kernel. By Thomas B. Osborne and Clark C 

 Voorhees. Am. Chem. Jour. XV (1893), pp. 392-471. 



