CHAPTER XXVII 



The Use of Lime in Agriculture. 



In order to be fertile, besides the organic 

 matters contained in humus and manure, 

 the ground must hold chalk, sand and clay. 

 It may happen that the ground in its natural 

 condition does not contain enough of these, 

 or that it may be altogether deficient in one 

 or other of them. In this case the nature 

 of the ground must be corrected by the 

 supply of that which is lacking. So land 

 which is too sandy is improved by chalk 

 and clay ; while that which is too strong and 

 contains too much clay, is improved by sand, 

 and still more by chalk. The mineral sub- 

 stances which are added to the ground to 

 correct its nature also help in the nutrition 

 of plants, and may therefore be looked upon 

 as mineral manures. 



One of the most valuable of these is lime, 

 which is not only indispensable for land that 

 contains no chalk, but is also required for the 



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