n
reasoning upon the subject of mineral concretion, is this: They see,
that by means of water a stony substance is produced; and, this stony
body so much resembles mineral marble as to be hardly distinguishable in
certain cases. These mineral philosophers then, reasoning in the manner
of the vulgar, or without analysing the subject to its principle,
naturally attribute the formation of the mineral marble to a cause
of the same sort; and, the mineral marble being found so intimately
connected with all other mineral bodies, we must necessarily conclude,
in reasoning according to the soundest principles, that all those
different substances had been concreted in the same manner. Thus, having
once departed one step from the path of just investigation, our physical
science is necessarily bewildered in the labyrinth of error. Let us
then, in re-examining our data, point out where lies that first devious
step which had been impregnated with fixed air, or carbonic acid gas,
(as it is called), dissolves a certain portion of mild calcareous
earth or marble; consequently such acidulated water, that is, water
impregnated with this gas, will, by filtrating through calcareous
substances, become saturated with that solution of marble; and, this
solution is what is called a _petrifying water_. When this solution is
exposed to the action of the atmosphere, the acid gas, by means of which
the stony substance is dissolved, evaporates from the solution, in
having a stronger attraction for the atmospheric air; it is then that
the marble, or calcareous substance, concretes and crystallises,
separating from the water in a sparry state, and forming a very solid
stone by the successive accretion from the solution, as it comes to
be exposed to the influence of the atmosphere in flowing over the
accumulating body. Here is the source of their delusion; for, they do
not distinguish properly the case of this solution of a stony substance
concreting by means of the separation of its solvent, and the case of
such a solution being in a place where that necessary condition cannot
be supposed to exist; such as, e.g., the interstices among the particles
of sand, clay, etc. deposited at the bottom of the sea, and accumulated
in immense stratified masses.

No example can better illustrate how pernicious it is to science to have
admitted a false principle, on which a chain of reasoning is to proceed
in forming a theory. Mineral philosophers have founded their