390 V. KOZAI, M. TOYOXAGA AND M. NAGAOKA. 



rhcsphoinc 





Increas 



e per 



frame. 





Increas 



e caused. 



acid 

 applied 

 pel" frame 

























Kinds of phospliatic 

 manure. 



in 



in 



i]T 



in 



in 



by 100 grms. of 



unrecovereu 

 phosphoric acid 



bj- 100 



grms. of 

 original 

 phosphoric 

 acid in the 



ill 



1892 



i8q^ 



1894 



I S91 



1S90 



in 



in 



in 



in 



1890. 















1892 



1893 



1S94 



1 89 1 



first season 

 (^1890). 



Grm?. 















Orn.v 



Gr... 



Grn.j 





Grms, 



3-^9 



Doul'le surcrpho=pliate 





21 





34 



243 



— 



752 



— 



•153 



6247 



7 7S 





32 



22 





97 



352 



561 



3S4 



— 



1516 



4524 



4-59 



1 Vccpita tc<l phosj >ha le. . 



2o 



21 





49 



307 



913 



704 



— 



1424 



Dt)00 



9.1S 





35 



20 





144 



416 



507 



38S 



— 



1912 



4532 



6.97 



I'eruvian tjuano 



21 



T c 



lo 



34 



122 



146 



354 





59- 



1^08 



2095 











1394 





69 



51 



41 



186 



195 



564 



429 



352 



1428 



1393 



6.SS5 



Tlioma? phosphate 



37 



41 



19 



133 



213 



671 



771 



370 



2240 



3093 



1377 





95 



70 



35 



204 



322 



845 



642 



32S 



1652 



2339 



6.8S5 



Steamed h>oiie dust .... 



19 



20 





142 



229 



348 



4SI 





2393 



3326 



13.77 





hg 



55 



41 



243 



3»i 



831 



532 



410 



2084 



2;0O 



G.8S5 



Crude bone dust 



14 



33 





lOI 



259 



260 



610 





1717 



3762 



13 77 





37 



55 



23 



I So 



454 



344 



526 



225 



1545 



5295 



6.885 

 1377 





26 



5 





34 

 76 



125 

 259 



413 

 218 



82 





529 



1S16 





26 



25 



12 



204 



99 



595 



1S74 



6.S85 





22 



20 



25 



40 



56 



328 



304 



385 



561 



313 









i:>-77 





44 



21 



-* -> 

 0- 



136 



50 



327 



155 



245 



S26 



■» ^ ^ 



We sec from the above table that the after effect of various 

 phosphatic manures, though perceptible in the fourth or e\ en in the 

 fifth season after their application, are not so great as one might 

 anticipate. Already in the second season their action Avas con- 

 siderably diminished, with the only exception of the peruvian guano 

 Avluch increased the crops by nearly the same proportion. Double 

 superphosphate and precipitated phosphate showed a verj- insigni- 

 ficant after-effect, and in the fifth season, not the least action was to 

 be observed. Steamed and crude bone dusts showed a more long 

 continued action than the two kinds of manure just mentioned, but 

 in small doses they were also no longer effective in the fiftli year. 



