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STATE BOARD OF AGRICULTURE) 



GENERAL DISCUSSION 



The causes of the reaction of soils must be considered fundamentally 

 the same as for other chemical agents, and that soil acidity is due to. 

 an excess of hydrogen ions and soil alkalinity to an excess of 

 hydroxyl ions. Since mineral soils neutralize both acids and bases 

 the active chemical constituents must be amphoteric in nature. This 

 assertion may also be applied to alkaline soils as data are herein 

 presented showing that the reaction between soil and Ca(0H)2 does 

 not stop when soils are neutralized with this reagent. Evidently al- 

 kaline soils contain salts or acids with replaceable hydrogen in their 

 structure or produce hydrogen ions through their dissociation with 

 water. The specific nature of active mineral soil compounds is be- 

 lieved to be largely alkali soil bases combined with complex silicic 

 acids forming amphoteric salts, together with free complex silicic 

 acids. In this work only major reactions or resultant effects were 

 studied and hence it was not known if the reactive soil compounds 



