142 Report of Farmees' Institutes 



amendment, is due largely to acid silicates wliicli are formed 

 during the leaching process. These acid silicates neutralize lime 

 just as do the acids. The acid silicate formation is represented 

 by the following equation, simply expressed, together with its 

 analogy, rock phosphate: 



Lime Lime 



(NaoO) or (K^O) or Lime (Silicic acid) 3 (neutral) Lime (Phosphoric acid), 



(NaoO) or (KnO) or Lime Lime 



(after leaching) (after leaching) 



Water Water 

 (NaaO) or (KoO) or Lime (Silicic acid) 3 (acid Lime Phosphoric acid) j 



(NaoO) or (K^O) or Lime reacting) Lime 



]!^ow the neutralization of lime requirement, which is in reality 

 the fixation or decomposition by the soil of applied carbonate of 

 lime through reaction with such acid salts, transpires both ex- 

 tensively, if not entirely, when leaching is not transpiring, and 

 when the free-moving soil water is not heavily impregnated with 

 carbonic acid gas. In other words, if in the laboratory we shake 

 up a mixture of carbonate of lime, soil and distilled water, we get 

 a greater decomposition, fixation or neutralization of lime than we 

 do if carbonated water be used instead of the gas free water. 

 This, then, is what theoretically becomes of the lime which we 

 apply. 



FIELD DATA 



Having thus considered the influence of source upon fineness 

 and that of fineness of the carbonate upon reaction with and con- 

 servation in soil, we come to the meagre available supply of 

 field data. 



Since the Pennsylvania Station results were obtained from 

 amounts of CaO and ground limestone not chemically equivalent, 

 together with the fact that the treatments are excessive and not 

 equally distributed, we have in so far as we know only the results 

 of the Rhode Island and Cornell stations. These we are able to 

 give through the courtesy of Doctors Hartwell and Lyon for their 

 respective stations. 



