136 



Percentage relation of the fixing power of one soil for bases. 



ABSORPTIVE POWER OF SOILS FOR PHOSPHORIC ACID. 

 OBSERVATIONS BY O. KULLENBERG.* 



In the experiments here cited 100 grams of soil were digested 

 3 days in 250 c. c. of solution hefore the determinations, were 

 made the soil used being the same as that cited on. p. 118. Three 

 phosphate salts were used in these trials, and each in solutions 

 having five concentrations. The results are next given. 



Amounts of phosphoric acid absorbed by one soil from solutions of 

 different kinds and strengths. 



The mean fixation of phosphoric acid from the potash solu- 

 tions is much larger than that from the other two salts, the per- 

 centage relations being: 



"Hoffman's Jahresbericht der Agrikultur-Chemie, 1865, p. 17. 



