MOVKMK.XTS OK SALTS I .\ SOILS. 



87 



Relative concentrations of magnesia in the surface inch of 8 



soil types. 



From the data of the table it is seen that the movement of 

 magnesia into the surface inch has been enough to increase that 

 which may be recovered by water alone to 345.46 parts per 

 million, as an average of the 8 soil types after 50 days of cap- 

 illary action. There was magnesia enough added to these soils 

 with the solution to represent about 9 parts per million, which, 

 added to 22.92, gives 31.92 as the amount which should be re- 

 covered from the bottom layer if no change had taken place as 

 the result of the treatment. The mean amount which was re- 

 covered from the bottom layer was 18.66 parts per million, only 

 a little more than one-half the amount called for with no 

 change. The top layer of soil had increased its content of re- 

 coverable magnesia, after 50 days, about 18-fold, which is rela- 

 tively more than had occurred with the lime, that increase being 

 12-fold. 



The differences between the magnitudes of the movements 

 of magnesia in the two groups of soils appear to be about such 

 as would be expected from the differences in the amounts of 

 the water-soluble magnesia which has been recovered from the 

 untreated soils of the two groups. 



