342 



now r-Rors fkkb. 



This f:ict is made evident hy the following data furnish- 

 ed by PctiTS. The soils employed were 



No. 1. Unaltered Soil. 



No. 2. Soil heated with hydrochloric acid for some 

 time, then thorouglily washed with water. 



No. 3. No. 2, boiled with 10 grams of sulphate of lime 

 and water, and washed. 



No. 4. No. 2, boiled with solution of 10 grams of chlo- 

 ride of calcium, and well washed with water. 



No. 5. No. 2, boiled with water and 10 grams of car- 

 bonate of lime. 



No. 6. No. 2, boiled with solutiou of bicarbonate of 

 lime, and washed. 



Portions of 100 grams of each of the above were placed 

 in contact with 250 c.c. of ' \^^ solution of chloride of po- 

 tassium for tlirce days. Tlie results are subjoined: 



It is seen that the soil which had been waslied with 

 acid, absorbed but one-ninth as much as tlie unaltered 

 earth. The treatment with the various lime-salts increas- 

 ed the absorbent power, in the order of the Table, until 

 in the last instance it surpassed that of the original soil. 

 Here, too, we observe that the absorption of potash ac- 

 companies and is made possible by the displacement of 

 other bases, (in this case almost entirely lime, since the 

 treatment with acid liad nearly removed the others). We 

 observe further that the quantity of chlorine remained 

 the same throughout (within the limits of experimental 

 error,) not being absorbed in any instance. 



Way first showed that the absorptive power of the soil 



