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ILLINOIS STATE ACADEMY OF SCIENCE 



TABLE 4. 



Phosphorus extracted with distilled water and fifth normal nitric 

 acid from different phosphatic fertilizers. 250 c.c. of either acid or 

 water were used on fertilizer which contained per sample 4 mgs. of 

 phosphorus. 



Water Soluble Fifth normal HN0 3 Soluble 



Tennessee rock phosphate. 

 Double acid phosphate.... 



Slag A 



Slag B 



Slag C 



Slag D 



Birmingham Slag , 



Blue Rock 



Florida Soft Rock 



Apatite 



Iron phosphate 



Aluminum phosphate 



Acid phosphate 



Steamed bone meal 



Acid alone 



Recovery of phosphorus from 25 gms. of Brown Silt Loam and 

 Brown Gray Silt Loam treated with 4 mgs. of phosphorus of either 

 Tennessee Rock Phosphate or Double Acid Phosphate. Five consecu- 

 tive extractions were made with fifth normal nitric acid. 



Brown Silt Loam Brown-gray Silt Loam 



