NITROGEN 125 



displace potassium, sodium, or calcium. Ammonia salts 

 are constantly forming in the soil; thus nature has fur- 

 nished a means for their conservation if the nitrification 

 is not rapid enough to take up the ammonia formed. The 

 fact that the four basic materials enumerated above are 



FIG. 45.* Blasting a test hole in caliche to obtain nitrate of soda. 



held in the relative order of their agricultural value is 

 significant. 



There is another action which may cause calcium to 

 liberate sodium, potassium, or ammonium; sodium to 



* Figs. 45-50 are furnished by The Nitrate of Soda Propaganda, 

 William S Myers, Director. 



