EXPERIMENT STATION BULLETINS. 



325 



TABLE 4. — Fixation of calcium from Ca{NOi)z and CASOi. 



Calcium added 0.4019 gm. NO' added 1.260 gm. 

 Calcium added 0.3085 gm. SO^ added 0.7423 gm. 



TABLE 5. — Fixation of calcium and magnesium from the chlorides. 



Calcium added 0.408 gm. Chlorine added 0.7002 gm. 

 Magnesium added 2581 gm. 

 Chlorine added 0T7523 gm. 



Tables 4 and 5 contain some interesting and important results and estab- 

 lish quite conclusively that the fixation of calcium in these soils depends 

 upon their content of replaceal^le magnesium and the fixation of magnesium 

 upon their content of replaceable calcium. The alkaline soils fixed greater 

 cjuantities of calcium and magnesium than did the acid soils of the same 

 class except, again, the acid clay loam which fixed a greater quantity of 

 magnesium and released a greater ciuantity of calcium than the alkaline clay 

 loam, a result comparing with the fixation of potassium and ammonia by 

 these soils from the salts studied. The alkaline clay loam, however, fixed 

 more calcium from the calcium salts and released more magnesium from the 

 potassium and ammonia treatments than did the acid clay loam. Mag- 



