PROPERTIES OF LIME. 61 



million pounds, seven thousand pounds of hydrate 

 )f lime would be made soluble for the use of 

 plants, if that amount were present. 



Burnt lime is more beneficial than the car- 

 bonate, because it more readily neutralizes the 

 acids contained in the soil, and causes the de- 

 composition of the vegetable matter therein. 

 This change is effected as follows : Most soils 

 contain a considerable amount of organic or 

 vegetable matter, surrounded by and saturated 

 with an atmosphere of carbonic acid, which 

 prevents free access of oxygen, the free access 

 of which is absolutely necessary to the decom- 

 position of this organic and vegetable matter 

 Now, if burnt lime be intimately mixed with the 

 soil, it absorbs this carbonic acid, and oxygen 

 takes its place, and decomposition of this matter 

 is the result. The lime, after indirectly pro- 

 ducing this result, answers all the useful pur- 

 poses of carbonate of lime in the form of ground 

 limestone, and as it is found in marl ; hence its 

 greater value, independent of other considerations. 



The office of lime in the liberation of nitrogen, 

 as ammonia, from organic substances, is another 

 valuable property. As nitrogen is an element 

 necessary to the healthy growth of grains and 

 plants used for food, its value herein is apparent. 



Lime has also a beneficial effect on the 

 inorganic or mineral matter in soils. Should 



