146 



From the data in this table it will be seen that the results are 

 in some ways very different from those just cited. In but one 

 case was quite all the phosphoric acid removed from the solution 

 but the solution was a little stronger as used on this soil. Silica 

 was more soluble in the salt solution than in distilled water, but 

 not as much so as in the Janesville Loam, except in the third and 

 fourth feet. 



The lime has behaved very differently, except in the fourth 

 foot, very large amounts of it going into solution in the first and 

 second feet, while in the fourth absorption has occurred. 



The different depths have absorbed the potash very unequally, 

 the surface foot taking nearly double what the second has taken. 



In the case of the sulphuric acid, too, there is a strong con- 

 trast, very much larger amounts having been absorbed, except 

 in the second foot, where a notable amount has gone into solu- 

 tion from the soil itself. 



If it be held that the comparison should be made between the 

 amounts added to the soil in the solution and the amounts 

 recovered from the solution afterwards, of course, quite dif- 

 ferent statements would be made, but we see little reason to 

 ignore the readily water-soluble salts present in the soil at the 

 start. 



Another set of soil samples, duplicates of those just described, 

 were treated in the same way, except that contact of the solution 

 with the soil was continued 72 hours instead of 24, the identical 

 solution being used. 



The results obtained are recorded in the next table. 



