6o6 



Journal of Agricultural Research 



Vol. VI, No. 16 



Table XI. — Yields of wheat and soybeans (in grams per pot on the water-free basis) in 

 dolomite, magnesite, and sand — series I and J 



Table XII shows the analyses of wheat grown in series I. 



Table XII. — Analysis of straw of wheat grown in dolomite, magnesite, and sand — 



series I 



Pot No. 



174 

 173 

 176 



175 

 178 

 177 

 180 

 179 



Composition of plants. 



Calcium. 



Mgm. 



I.32 



I. 21 



IO.88 



21.36 



8.87 



16. 16 



10. 26 



24. II 



Per cent. 

 O.44 



135 



68 



445 

 493 

 305 



54 

 455 



Magnesium. 



Mgm. 

 O.38 

 I. 26 

 13.04 

 36.78 

 18.03 

 40. 54 

 11.38 

 22. 15 



Per cent. 



0. 127 



• 14 

 .815 



.783 



1. 002 



.765 

 •599 

 .418 



Molecular 

 ratio of 

 calcium 

 to mag- 

 nesium. 



5: 2.4 

 5: 7-i 

 5: 9-9 

 5:14.6 

 5:16.9 

 5:21 

 5: 9-2 

 5: 7-6 



Comparisons of the contents of plants at different stages of growth are 

 reported in Table XIX. 



THE EFFECT OF MAXIMUM QUANTITY OF CALCIUM AND MAGNESIUM UPON 

 WHEAT AND SOYBEANS IN SAND (SERIES K) 



Analysis of sand treated by different methods shows the hot-extracted 

 sand to contain only slightly less calcium but considerably less magne- 

 sium than the cold-extracted sand. 



Table XIX shows the analysis of wheat and soybeans grown in such 

 sands. It can be seen that the soybeans contained only slightly more of 

 these two elements than was in the seed, but it must be remembered that 

 scarcely any growth occurred. However, the wheat, pots 193 to 196, 

 contained from 12 to 22 times as much calcium and 4 times as much 



