Manure consists of all kinds of substances, whether of vegetable or animal origin, which have undergone the putrid fermentation, and are consequently decomposed, or nearly so, into their elementary principles. And it is requisite that these vegetable matters should be in a state of decay, or approaching decomposition. The addition of calcareous earth, in the state of chalk or lime, is beneficial to such soils, as it accelerates the dissolution of vegetable bodies. Now, I ask you, what is the utility of supplying the soil with these decomposed substances?
CAROLINE.
It is, I suppose, in order to furnish vegetables with the principles which enter into their composition. For manures not only contain carbon, hydrogen, and oxygen, but by their decomposition supply the soil with these principles in their elementary form.
MRS. B.
Undoubtedly; and it is for this reason that the finest crops are produced in fields that were formerly covered with woods, because their soil is composed of a rich mould, a kind of vegetable earth, which abounds in those principles.
EMILY.
This accounts for the plentifulness of the crops produced in America, where the country was but a few years since covered with wood.
CAROLINE.
But how is it that animal substances are reckoned to produce the best manure? Does it not appear much more natural that the decomposed elements of vegetables should be the most appropriate to the formation of new vegetables?
MRS. B.