152 



BULLETIN 



The final results of Voelcker's determinations are given in the 

 next table. 



Composition of liquid manure before and after filtration through 



two soils. 



The amount of soil used in these cases was 20,000 grains. 

 The 70,000 grains of solution contained 09 parts per million of 

 phosphoric acid and from this solution the pasture land increased 

 its phosphoric acid content 154.5 parts per million and the sandy 

 soil 145.5 parts. From a solution containing 241. T parts per 

 million of potash the pasture land absorbed 586.5 parts per mil- 

 lion of itself and the sandy soil 245.5 parts per million. 



It will be further observed that the manure solution reduced 

 the amount of lime carried by the pasture land, taking into itself 

 13. 73 grains, whereas the sandy soil exerted an opposite effect, 

 withdrawing 3.35 grains. The two soils differ, therefore,, in 

 their effects upon this solution by the sum of these amounts, or 

 17.08 grains; one of them yielding from itself 686.5 and the 

 other taking to itself 167.5 parts per million of its dry weight. 

 One of these soils showing that it possessed so much lime, in sol- 

 uble form, that it could, under the conditions imposed, give up 

 about a ton per acre-foot; while the other was in so different a 

 condition that it must draw from the same solution and fix about 

 its grains, more than 500 Ibs. of lime per acre-foot With differ- 

 ences like these between the effects of two soils upon one and the 



