ich would impede the growth of the plant, &c. we may obtain a
produce an hundred fold more abundant than the earth would spontaneously
supply.

EMILY.

We have a very striking instance of this in the scanty produce of
uncultivated commons, compared to the rich crops of meadows which are
occasionally manured.

CAROLINE.

But, Mrs. B., though experience daily proves the advantage of
cultivation, there is still a difficulty which I cannot get over.
A certain quantity of elementary principles exist in nature, which it is
not in the power of man either to augment or diminish. Of these
principles you have taught us that both the animal and vegetable
creation are composed. Now the more of them is taken up by the vegetable
kingdom, the less, it would seem, will remain for animals; and,
therefore, the more populous the earth becomes, the less it will
produce.

MRS. B.

Your reasoning is very plausible; but experience every where contradicts
the inference you would draw from it; for we find that the animal and
vegetable kingdoms, instead of thriving, as you would suppose, at each
other's expense, always increase and multiply together. For you should
recollect that animals can derive the elements of which they are formed
only through the medium of vegetables. And you must allow that your
conclusion would be valid only if every particle of the several
principles that could possibly be spared from other purposes were
employed in the animal and vegetable creations. Now we have reason to
believe that a much greater proportion of these principles than is
required for such purposes remains either in an elementary state, or
engaged in a less useful mode of combination in the mineral kingdom.
Possessed of such immense resources as the atmosphere and the waters
afford us, for oxygen, hydrogen, and carbon, so far from being in danger
of working up all our simple materials, we cannot suppose that we shall
ever bring agriculture to such a degree of perfection as to require the
whole of what these resources could supply.

Nature, however, in thus furnishing us with an inexhaustible stock of
raw materials, leaves it in some measure to the ingenuity of man to
appropriate them to its own purposes. But, like a kind parent, she
stimulates him to exertion, by setting the example and pointing out the
way. For it is on the operations of nature that all the improvements of
art are founded. The art of agriculture consists, therefore, in
disco