THE PHYSICAL ACTION OF LIME ON CLAY SOILS 



21 



ADSORPTION OF METHYLENE BLUE BY SOILS TREATED FOR 100 DAYS 

 (Readings in divisions equivalent to 100 of standard) 



ADSORPTION OF METHYLENE BLUE BY SOILS TREATED FOR 225 DAYS 



Each figure in the preceding tables is the average of triplicate deter- 

 minations. While calcium hydrate decreases adsorption the most when 

 10 ton treatments are used, precipitated carbonate and gypsum are more 

 efficient with slight applications. 



Studies were conducted with safranine in order to observe the effect 

 of salts in the adsorptive power of the organic matter. Preliminary 

 experiments indicated that adsorptions could not be conducted with 

 safranine in the presence of sodium and magnesium carbonates. The 

 results are as follows : 



ADSORPTION OF SAFRANINE BY SOILS TREATED FOR 45 DAYS 



ADSORPTION OF SAFRANINE BY SOILS TREATED FOR 225 DAYS 



