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tity of inert vegetable matter that it contains. The 

 solution of the question whether marie, mild lime, or 

 powdered limestone ought to be applied, depends upon 

 the quantity of calcareous matter already in the soil. 

 All soils are improved by mild lime, and ultimately 

 by quicklime which do not effervesce with acids j and 

 sands more than clays. 



When a soil deficient in calcareous matter contains 

 much soluble vegetable manure, the application of 

 quicklime should always be avoided, as it either tends 

 to decompose the soluble matters by uniting to their 

 carbon and oxygene so as to become mild lime, or it 

 combines with the soluble matters, and forms com- 

 pounds having less attraction for water than the pure 

 vegetable substance. 



The case is the same with respect to most animal 

 manures ; but the operation of the lime is different in difc 

 ferent cases, and depends upon the nature of the animal 

 matter. Lime forms a kind of insoluble soap with oily 

 matters, and then gradually decomposes them by se- 

 parating from them oxygene and carbon. It combines 

 likewise with the animal acids ; and probably assists 

 their decomposition by abstracting carbonaceous mat- 

 ter from them combined with oxygene ; and conse- 

 quently it must render them less nutritive. It tends to 

 diminish likewise the nutritive powers of albumen from 

 the same causes ; and always destroys to a certain 

 extent the efficacy of animal manures, either by com- 

 bining with certain of their elements, or by giving to 

 them new arrangements. Lime should never be ap- 

 plied with animal manures, unless they are too rich, 



