ABOUT FRUITS, FLOWERS AND FARMING. 57 



acid expelled by strong heat, and in that state applied to 

 seeds, will assist the germination. If exposed to the air it 

 attracts carbonic acid and becomes again a carbonate, and 

 useless to seeds. 



Where lime is employed upon the soil, it is either as a 

 mere article of vegetable food, or, as a chemical agent, to 

 change the condition of other, ingredients of the soil. All 

 good soils contain lime ; of ninety-four different cultivated 

 soils in Rhode Island, analyzed by Professor 0. T. Jackson, 

 eighty-nine contained lime. Ruffin, in his essay on calcare- 

 ous manures, says, after a large induction of fact, " that all 

 soils naturally poor, are certainly destitute of calcareous 

 earth." When there exists in the soil, already, enough lime 

 for the wants of vegetation, the addition of more will pro- 

 duce no effect upon the crop. New lands, and old land not 

 run down, and naturally rich in lime, may require none. 

 But lime is applied not alone as food directly offered to 

 vegetation, but to act upon and change the soil itself. 



It neutralizes free acids which exist in the soil. This is 

 done with quick-lime or air-slaked ; the first combining 

 directly with the acid the second by liberating its carbonic 

 acid and then combining with the acid of the soil, leaving 

 the carbonic acid to be food for plants. It is very well 

 known by those accustomed to use peaty substances for 

 manures, and meadow mud, that they will rather injure than 

 benefit soils, until their acid has been neutralized. 



Lime decomposes vegetable fibre, and reduces tough lig- 

 neous substances, to a consideration in which they can be 

 appropriated by plants. For this purpose quicklime should 

 be used and may be applied at the rate of from twenty to 

 thirty bushels t the acre. 



Lime enters into combination with sand or silex, forming 

 a substance different from either of them. Even strong 

 clays will be found to contain much silex ; and lime, by com- 

 bining with it, makes the soil friable or crumbling. 



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