354 SOILS, PBOFEBTIES AND MANAGEMENT 



This, however, has no significance so far as danger 

 from loss of a soluble fertilizer constituent is concerned, 

 since water, even after a heavy rain, would not pass so 

 quickly through the soil that absorption would not take 

 place, except possibly in the case of soil of a very coarse 

 texture. The depth through which the substance is 

 distributed in the soil may, however, be influenced by 

 the time required for its absorption. Ordinarily ferti- 

 lizers do not penetrate very far into the soil. Demolon 

 and Bronet ^ have investigated the rate and distance of 

 penetration of certain soluble salts in soils, and find that 

 a total rainfall of ten inches is not sufficient to carry down 

 sodium nitrate in a sandy soil to a depth of eight inches. 



253. Insolubility of certain absorbed substances. — 

 Although bases once absorbed may be easily displaced 

 by other bases, it is difiicult to dissolve them from the 

 soil with pure water. Peters^ treated 100 grams of soil 

 with 250 cubic centimeters of water containing potassium 

 chloride, of which 0.2114 gram of IV2O was absorbed. 

 The soil was then leached with distilled water, using 125 

 cubic centimeters of water daily for ten days. At the 

 end of that time 0.0875 gram of K2O had been removed, 

 or at the rate of 28,100 parts of water to one part of 

 K2O dissolved from the soil. Henneberg and Stoh- 

 mann^ found that it required 10,000 parts of water 



1 Demolon, A., and Bronet, G. Sur la Penetration des 

 Engrais Solubles dans les Sols. Ann. Agron., Tome 28, pp. 

 401-418. 1911. 



2 Peters, E. Ueber die Absorption von Kali durch Aeker- 

 erde. Landw. Vers. Stat., Band 2, Seite 113-151. 1860. 



3 Henneberg, W., and Stohmann, F. Ueber das Verhalten 

 der Aekererde gegen Losungen von Ammoniak und Ammoniak- 

 salzen. Jour, f . Landw., Neue Folge, Band 3 (Der ganze Reihe 

 siebenter Jahrgang), Seite 25-47. 1859. 



