286 AGRICULTURAL ANALYSIS 



ing the action which takes place in the soil will show that the 

 plant itself exudes no solvent material as has been assumed by 

 many investigators, unless it be the excretion of carbon dioxid. 

 The processes of solution which take place in the soil, from a 

 study of all the conditions which obtain, must be regarded more 

 as operations depending upon the soil itself than as largely in- 

 fluenced by the growing plant. At the present time, however, 

 the solution of the problem, experimentally, in so far as fineness 

 of subdivision is concerned, has perhaps been well answered and 

 it is now clearly understood that in so far as the assimilation 

 processes go on in the soil, they are favored more particularly by 

 the fineness of the subdivisions than by any other factor. Even 

 in soils which are not distinctly acid the fineness of subdivision 

 greatly favors solution, and in regard to the other causes of solu- 

 tion and absorption of these bodies, excluding those due to 

 weathering, it is probable that our ideas in the near future must 

 undergo fundamental revision. Just at present we are unable to- 

 specify whether or not the frequent application of these par- 

 tially insoluble phosphatic fertilizers is advisable or not. Some 

 authors urge that when the crop is to be planted in the spring these 

 fertilizers should be applied in the autumn, while some are of the 

 opinion that equally good results are obtained by applying them 

 at the time of sowing. 44 



Reitmair concludes from his investigations that the extraction- 

 of bones in such a way as to remove practically all of their nitro- 

 gen does not unfit them for fertilizing purposes, since the resid- 

 ual phosphate of lime when reduced to a proper state of fineness 

 is still valuable for its phosphoric acid. 



** Reitmair, Wiener landwirtschaftliche Zeitung, 1905, 55 : 879, 889. 



