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By this kind of operation, lime renders matter 
which was before comparatively inert, nutritive ; 
and as charcoal and oxygene abound in all vege- 
table matters, it becomes at the same time converted 
into carbonate of lime. 
Mild lime, powdered limestone, marles or chalks, 
have no action of this kind upon vegetable matter ; 
by their action they prevent the too rapid decom- 
position of substances already dissolved ; but they 
have no tendency to form soluble matters. 
It is obvious from these circumstances, that the 
operation of quicklime, and marie or chalk, depends 
upon principles altogether different. — Quicklime, 
in being applied to land, tends to bring any hard 
vegetable matter that it contains into a state of 
more rapid decomposition and solution, so as to 
render it a proper food for plants. — Chalk, and 
marie, or carbonate of lime, will only improve the 
texture of the soil, or its relation to absorption ; 
it acts merely as one of its earthy ingredients. — 
Quicklime, when it becomes mild, operates in the 
same manner as chalk ; but in the act of be- 
coming mild, it prepares soluble out of insoluble 
matter. 
It is upon this circumstance that the operation 
of lime in the preparation for wheat crops depends ; 
and its efficacy in fertilizing peats, and in bringing 
into a state of cultivation all soils abounding in hard 
roots, or dry fibres, or inert vegetable matter. 
The solution of the question, whether quicklime 
ought to be applied to a soil, depends upon the 
quantity of inert vegetable matter that it contains. 
The solution of the question, whether marie, mild 
