33 



mined according to the method described under artificial soils, 

 the quantities taken being calculated on a basis of the original 

 air dry soil. The quantities of phosphoric acid in the following 

 tables are calculated to this basis, and are therefore comparable 

 in all cases. 



SOIL "A." SOLVENT I PER CENT CITRIC ACID 



I,i me added. P2Os soluble. Per cent of 



total. 



None 0.028% 19.3 



None 0.030% 20.7 



One gram 0.031% 21.3 



One gram 0.032% 22.0 



Two grams 0.037% 25.5 



Two grams 0.038% 26.2 



SOIL "B." SOLVENT I PER CENT CITRIC ACID 



L,ime added. 1*20.5 soluble. Per cent of 



total. 



None 0.0068% .4.3 



None 0.0067% 4-3 



One gram 0.0132% 8.5 



One gram 0.0130% 8.3 



Twograms 0.0100% 6.4 



Two grams 0.0102% 6.5 



SOIL "A." SOLVENT HYDROCHLORIC ACID 



2OO 



L,ime added. P 2 O 5 soluble. Per cent of 



total. 



None 0.0030% 2.0 



None 0.0030% 2.0 



One gram 0.0043% 2 -9 



One gram 0.0041% 2.8 



Twograms 0.0040% 2.8 



Twograms 0.0038% 2.7 



n 



SOIL "B. SOLVENT HYDROCHLORIC ACID 



2OO 



The amount of phosphoric acid was too small to be deter- 

 mined. The addition of lime (one and two grams), seemed to 

 produce no effect on the solubility of the phosphoric in this soiL 



