e an effect upon
mineral substances different from that of the subterraneous power which
I would employ.

He then sets about combining metals with sulphur in the moist way, as if
that were any more to his purpose than is the making of a stalactite for
the explanation of marble. Silver and lead may be sulphurated, as he
says, with hepatic gas; but, Has the sulphurated solid ores of those
metals, and that of iron, been formed in the moist way, as in some
measure they may be by the fusion of our fires? But, even suppose that
this were the case, Could that explain a thousand other appearances
which are inconsistent with the operation of water? We see aerated lead
dissolved in the excavations of our mines, and again concreted by the
separation of the evaporated solvent, in like manner as stalactical
concretions are made of calcareous earth; but, so far from explaining
mineral appearances, as having had their concretions formed in the same
manner, here is the most convincing argument against it; for, among the
infinite variety of mineral productions which we find in nature, Why
does no other example of aqueous concretion ever occur upon the surface
of the earth except those which we understand so well, and which we
therefore know cannot be performed in the bodies of strata not exposed
to the evaporation of the solvent, a circumstance which is necessary.

I have given a very remarkable example of mineral fusion, in reguline
manganese, (as the reader will see in page 68.) It is not that this
example is more to the purpose of my theory than what may be found in
every species of stone; but this example speaks so immediately to
the common sense of mankind, (who are often convinced by a general
resemblance of things, when they may not see the force of demonstration
from an abstract principle) that I thought it deserved a place on that
account, as well as being a curious example, But more particularly to my
antagonist, who has been pleased (very improperly indeed) to try some
part of my theory in the fire, here is an example which should have
been absolutely in point, and without any manner of exception:--Has he
acknowledged this?--No; he has, on the contrary, endeavoured to set this
very example aside.

On this occasion, he says, "Manganese has been found in a reguline state
by M. de la Peyrouse, and in small grains, as when produced by fire.
True; but it was mixed with a large quantity of iron, which is often,
found in that for