It is a very difficult matter to tell how men came to know anything of
iron, and the art of employing it: for we are not to suppose that they
should of themselves think of digging it out of the mines, and
preparing it for fusion, before they knew what could be the result of
such a process. On the other hand, there is the less reason to
attribute this discovery to any accidental fire, as mines are formed
nowhere but in dry and barren places, and such as are bare of trees
and plants, so that it looks as if nature had taken pains to keep from
us so mischievous a secret. Nothing therefore remains but the
extraordinary circumstance of some volcano, which, belching forth
metallic substances ready fused, might have given the spectators a
notion of imitating that operation of nature; and after all we must
suppose them endued with an extraordinary stock of courage and
foresight to undertake so painful a work, and have, at so great a
distance, an eye to the advantages they might derive from it;
qualities scarcely suitable but to heads more exercised, than those of
such discoverers can be supposed to have been.

As to agriculture, the principles of it were known a long time before
the practice of it took place, and it is hardly possible that men,
constantly employed in drawing their subsistence from trees and
plants, should not have early hit on the means employed by nature for
the generation of vegetables; but in all probability it was very late
before their industry took a turn that way, either because trees,
which with their land and water game supplied them with sufficient
food, did not require their attention; or because they did not know
the use of corn; or because they had no instruments to cultivate it;
or because they were destitute of foresight in regard to future
necessities; or in fine, because they wanted means to hinder others