394 KOZAi, M. tovoxa(;a and m. nacaoka. 



Phosphoric acid 



Ivind of phosphntie 

 manure. 



Phosphoric acid 

 aljsorbed from 

 ll'.c residue. 



J'hosphoric acid 

 absorljed from the 

 iriginal manure 



o 



00 



In 0 

 ■r. 



N 



left in the soil 1893 

 (Jrnis. 



Orms. 



U 



3 



in the ist, 2nd, 3rd, 

 4th, & 5th seasons, 

 /n 



•3 



> 

 < 







2.624 



1 )ouble supeqihi ■>phate . 









,,-5 ( 





7.7S 



30.0 



5438 





— 





" — * 



f 



30.0 : 



3 1 -3 



4-59 



36.8 





Precipitated pliosiiliate.. 









i6 S 1 





















33-5 



9.18 





6.418 





— 











30. 1 ' 





6,07 



17-') 



5-744 



Peruvian i^uano 



0.050 



0.0 



0 7 



18.6 ) 





»3-94 



16.6 



U.643 



,. 



0.073 



0.6 



c-5 



17.1 ) 



•7-9 



0.003 



-5o 



5.142 



'1 homas jihosphate 



0.0. 



0-,1 



C-4 



25-7 ) 



















22.6 i 



24.2 



13-77 



22.2 



10.686 





0.055 



0-5 



0.4 





6.S8s 





- 5-289 



Steamed hone dust 













13-77 



26.0 



10.059 





0.071 



0.7 



C'-5 



27.4 ) 



25-3 



6.885 



23-i 



5.279 



Crude hone dust 















25.6 















24-7 



13-77 



10.245 





0.035 



0-3 



0.3 



25.9 ! 





6.885 



11.4 



6.103 











11.4 j 





















11.6 



13-77 



II.7 



12.158 





0.010 



0.1 



0.1 



,,.8 f 





6.885 



5-7 



6.49c 





0-035 



0.5 



o-S 





















5.6 1 



5-9 



13-77 



5-3 



13-043 





0.03S 



0-3 



0-3 





In harnvjny with the action of the various phosphatic manures 

 in increasing the yield of grain we find from the above tables that 

 the projjortions of the phosphoric acid assimilated from the residues 

 are much smaller than those absorbed from the freshly applied 

 phosphates and that a large fraction of assimilable ijhosphoric acid 

 of the manures was converted in the course of time into difficultly 

 assimilable forms and was simply left unrecovered in the soil. This 

 fact is, as already stated, of great practical importance and warrants 

 the ajDplication of easily soluble jihosphatic manures for each crop, as 

 we do wish rapidly acting nitrogenous manures. 



