Improving the Condition of the Soil 



possibility of reclaiming much land that without 

 their aid would be uncultivable. 



The rdles played by the two improvements are 

 very different in their effects, so that we shall have 

 to discuss them separately. Let us first examine 

 the calcareous improvements. 



Calcareous Improvements. 



There are many calcareous improvements. Their 

 action varies, evidently, according to the chemical 

 form of their constituents, the proportions in which 

 these are encountered, and the soil on which they 

 are employed. 



Among them lime is the most important. After 

 it comes limestone, chalk, gypsum, etc., coal 

 ashes, turf ash, etc. We will treat each of these 

 substances separately, establishing at the beginning, 

 however, a well-defined distinction between lime and 

 the carbonates of calcium or limestone, because these 

 frequently give rise to confusion. 



Although derived from carbonate of calcium 

 (CaCos), caustic lime (CaO), whether quick or slaked, 

 has very distinct and important properties which 

 the carbonate does not possess, and which make its 

 value, whilst the lime becoming recarbonated in the 

 soil very rapidly acquires the properties of limestone. 

 It is obvious that we should not pay the cost of 

 burning lime where limestone will suffice, but, on the 

 other hand, we should not apply limestone when 

 lime is necessary. 



Thus when wishing to destroy rushes one would 

 use lime. 



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