384 Y. KOZAI, M. TOVOXAGA AXD ^r. XAGAOKA. 



Thus the residues left from the smaller doses of phosphoric acid 

 were no longer available, while the residues from the larger doses 

 were assimilated by the plants to a certain extent. But the freshly 

 api^lied phosphoric acid was far more accessible to the plants than the 

 residues left in the soil. In order to show how much phosphoric 

 acid was assimilated from the sodium phosphate originally applied, 

 the following table has been prepared : 





I 





3 



4 



5 



('1 



Phosphoric acid applied per frame 

 in iSSo. Grnis 



[ 4oS 



j-9.i.^ 



■ 13.77 



[1836 



[22 95 



[ 27.54 



rerccntage consumption of the 

 phosphoric acid originally appU- 



|-20.5 



... 







|«5-9 



|i5-4 









3-5 



4-5 



5 4 



5-7 



.. 1891 



2.6 



4-7 



4-7 



4.6 



50 



3-9 



,. 1892 ... 









03 



I 0 







23-1 



27-5 



29-3 



28.8 



27-3 



26.3 



To study still further the after-action of sodium phosphate in 

 the fifth year after its application, we cultivated rice again on the 

 same plots in 1893, manuring them only with nitrogen and potash 

 in the form of the same salts and in the same proportions as in the 

 preceding year. The following table shows the quantities of 

 pIiosi:)lioric acid originally applied and tliose left unrecovered, as 

 well as the produce in the fifth season: 



