31

THE SURFACE OF THE GLOBE

system of absolute identity, or pantheism, produces all
phenomena or (what it thinks the same thing) all
beings by polarization similar to the two electricities;
and calling polarization, all opposition, every obstacle,
whether we consider its situation, nature, or functions,
it seems to oppose God and the world; in the world the
sun and planets; in each planet solidity and liquidity,
and pursuing this system, changing when needful its
figures and allegories, it reaches at last to the minutest
details of organized species. (1)
We must allow thatwe have selected the most
opposite examples, and that all geologists have not
carried the boldness of their conceptions as far as those
we have cited. But amongst those who have advanced
with more caution, and have sought arguments beyond
physics or ordinary chemistry, how much diversity of
opinion and contradiction have arisen!

OPPOSITION OF ALL THESE SYSTEMS.

According to one, all is precipitated successively by
crystallization: all was deposited as it now is; but the
sea which covered all has retired gradually.(2)
With another the materials of mountains are
incessantly lowered and carried away by rivers to the
depths of the ocean, there to become heated beneath
enormous pressure, and to form layers which the heat
that hardens them will one day elevate with violence.
(3)

(1) We particularly find this application of pantheism to
geology in the works of M. Steffens and M. Oken.
(2) M. Delamétherie admits crystallization as a principal cause
in his Geology.
(3) Hutton and Playfair: Illustrations of the Huttonian Theory
of the Earth. Edinb. 1802.

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ON THE REVOLUTIONS OF

A third supposes the liquid divided into a multitude
of lakes, amphitheatrically one above another, which,
after having deposited our layers of shells, have
successively broken down their banks to fill the basin
of the ocean.(1)
It is the theory of a fourth that the tides of seven or
eight hundred fathoms have, on the contrary, carried
off from time to time the bottoms of the sea, and cast
them as mountains and hills in the valleys, or on the
primitive plains of the continent. (2)
A fifth has thought that meteoric stones have fallen
successively from heaven, which have been the
component parts of the earth, and which bear the
imprint of their strange origin in the unknown beings
whose relics they contain. (3)
A sixth makes the earth hollow, and places in the
centre a diamond, which conveys itself by intervention
of comets from one pole to another,drawing with it the
centre of gravity and the mass of waters, and thus
alternately drowning the two hemispheres. (4)
We could quote twenty other systems, equally
contradictory with these. And do not let us be
understood as criticising the authors of them; onthe
contrary, we know that these opinions have generally
been elicited from men of genius and understanding,
who were not ignorant of facts to examine which many
of them had travelled far and long, and have added
many and important truths to the science.

(1) Lamanon, in many parts of the Journal de Physique, after
Michaelis, and many others.
(2) Dolomieu, ibid.
(3) MM. de Marschall: Recherches stir l'Origine et le
Developpement de l'ordre actual du Monde. Giessen 1802.
(4) M. Bertrand: Renouvellement Periodique des Continens
Terrestres. Hambourg, 1799.

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THE SURFACE OF THE GLOBE

CAUSES OF THESE CONTRADICTIONS

How then can such opposing facts occur in the
results of those who have started with the same first
principles to resolve the same problem?
Must it not be that the terms of the problem have
not all been thoroughly considered; which has left it to
this day undetermined, though capable of many
solutions, all equally plausible when this or that
condition Is overlooked; all equally unworthy of
adoption when a new condition arises, or when
attention is arrested by some well-known but neglected
fact.

THE NATURE AND TERMS OF THE PROBLEM.

To quit the language of mathematics, we will say
that nearly all the authors of these systems, having
only regarded certain difficulties which opposed them
more forcibly than others, have solved them in a
manner more or less plausible, and have thrown aside
others as numerous and important. One, for instance,
has only contemplated the difficulty of changing the
level of the sea; another, that of dissolving all
terrestrial substances in one and the same liquid; a
third, that of accounting for the existence of animals
in the frigid zone, which he supposed could only live
in the torrid zone. Exhausting on these points the
whole powers of their imagination, they thought they
had effected all in devising a means of answering
them. Besides, in neglecting other phenomena, they did
not always think of determining precisely the measure
and limits of those which they attempted to explain.
This is particularly true in reference to the

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ON THE REVOLUTIONS OF

secondary formations, which form the most important
and difficult part of the problem. For a long time
naturalists employed themselves very unavailingly in
determining the superstrata of their layers and the
relation of these layers with those sorts of animals and
plants whose remains they contain.
Are there animals and plants peculiar to certain
layers, and which are not met with in others?  What is
the species of those which first appear, or which come
after? Are those two species ever found together? Are
there variations in their return; or, in other words, do
the first again recur, and do the second then disappear?
Have these animals and plants all lived in the places
where their remains are found, or have some of them
been conveyed elsewhere? Do they all exist at present
any where, or have they been wholly or partly
destroyed? Is there a perpetual uniformity between the
antiquity of the layers and the resemblance or non-
resemblance of the fossils with living beings? Is there
a similarity of climate between fossils and those of
living beings which most resemble them? Can we
determine that the removal of these beings (if there has
been any) has been from north to south or from east to
west, or by scattering and mixture; and can we
distinguish the epochs of those removals by the layers
which have these marks impressed on them?
How can we decide on the actual state of the globe,
if we cannot answer these questions; if we have not
sufficient grounds to enable us to determine in the
affirmative or negative? Besides, it is but too true that
during a long period none of these points have been
absolutely cleared up; in fact, it was scarcely deemed
expedient to clear them up previous to the formation
of a system.

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THE SURFACE OF THE GLOBE

REASON WHY THESE PRELIMINARIES HAVE BEEN
NEGLECTED.

It may be assigned as a cause of this peculiar
neglect, that geologists have all been either naturalists
of the closet, who had themselves but very
superficially examined the structure of mountains, or
mineralogists who had not studied in sufficient detail
the innumerable varieties of animals, and the infinite
complication of their different component parts. The
former have only framed systems; the latter have made
admirable observations; they have in fact laid down the
foundations of the science, but were inadequate to the
task of elevating the superstructure.

PROGRESS OF MINERAL GEOLOGY.

In truth, the mineral portion of the great problem of
the theory of the earth has been studied with admirable
care by Saussure, and brought to a wonderful
development by Werner, and by the numerous and
talented disciples of his school.
The former of these celebrated men, scrutinizing
with indefatigable toil for twenty years the most
inaccessible mountainous districts, in a manner
attacking the Alps themselves in every direction, in
every defile, has laid open to us all the confusion of
the primitive formations, and has clearly traced the
secondary formations. The latter, availing himself of
the numerous excavations made in countries containing
the oldest mines, has fixed the laws relating to the
succession of layers; he has pointed out their relative
antiquity, and traced each through its respective

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ON THE REVOLUTIONS OF

change. It is he, and he only, who has given a date to
geology, as far as regards the mineral nature of the
layers; but neither Saussure nor Werner has determined
the fossilized organized species in each sort of layer,
with that necessary exactness which is so requisite,
from the prodigious number of known animals which
they contain.
Other men of science indeed studied the fossil relics
of organized bodies; they collected and published
drawings of them by thousands: their works will be
valuable collections of materials; but, more engrossed
with animals or plants, considered as such, than with
the theory of the earth, or regarding these petrifactions
or fossils. as curiosities rather than historical
documents, or, in truth, contenting themselves with
partial explanations on the relative bearings of each
relic, they have almost always neglected to seek for the
general laws of position, or the relation of fossils with
the layers. 

IMPORTANCE OF FOSSILS IN GEOLOGY.

And yet the idea of such a research was very
natural. How was it overlooked that it is to fossils
alone that must be attributed the birth of the theory of
the earth; that, without them we could never have
surmised that there were successive epochs in the
formation of the globe, and a series of different
operations? Indeed, they alone prove that the globe has
not always had the same crust, by the certainty of the
fact that they must have existed at the surface before
they were buried in the depths where they are now
found. It is only by analogy that we extend to
primitive formations that conclusion which fossils
enable us definitively to ascribe

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THE SURFACE OF THE GLOBE

to secondary formations; and if there were only
formations without fossils, no one could prove that
these formations were not simultaneously produced.
Again, it is to fossils, small as has been our
acquaintance with them, that we owe the little
knowledge we have attained respecting the nature of
the revolutions of the globe. They have taught us, that
the layers which comprise them have been
undisturbedly deposited in a liquid; that their
alterations have corresponded with those of the liquid;
that their exposure was occasioned by the removal of
this liquid; that these exposures have taken place more
than once. None of these facts could have been decided
on without these fossils.
The study of the mineral portion of geology, which
is not less necessary, which is even of still greater
utility with regard to the mechanical arts, is yet much
less instructive with relation to the object of which we
are treating.
We are in positive ignorance regarding the causes
which can have produced the changes of the substances
composing the layers; we do not even know the agents
which could have held certain of them in solution; and
— it is yet a matter of controversy, whether certain of
them owe their origin to water or fire. To come at
once to the point, we observe that there is a general
agreement on one point only; namely, that the sea has
changed its situation. And how should we know that if
we had no fossils?
Fossils, which have given birth to the theory of the
earth, have also furnished it with its principal lights,
the only ones which have been generally recognised
down to the present period.
It is this idea which has encouraged us to take up
the subject; but the field is immense; a single person

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ON THE REVOLUTIONS OF

could only glance over but a very trifling part. A
choice was to be made therefore, and we did not
hesitate. The class of fossils which forms the object of
this work at once determined us, because we saw that it
is at the same time more pregnant with precise results,
and yet less known and more rich in novel matters of
research.(1)

PARAMOUNT IMPORTANCE OF THE FOSSIL BONES OF
QUADRUPEDS.

It is apparent that the bones of quadrupeds conduct us,
by various reasonings, to more precise results than any
other relics of organized bodies.

In the first place, they characterize more clearly the
revolutions which have effected them. Shells prove
that the sea was once where they are now found; but
their change of species could only at the utmost
proceed from slight variations in the nature of the
liquid, or merely in its temperature.

They might have had relation to causes still more
accidental. There is nothing to assure us that at the
bottom of the sea, certain species, even certain genera,
after having occupied for a larger or shorter period
determinate situations, have not been forced away by
others. Here, on the contrary, all is precise; the
appearance of the bones of quadrupeds,

(1) My work has in fact proved the situation of this subject
when I took it up in spite of the admirable labours of Camper,
Pallas, Blumenbach, Merk, Sœmmering, Rusenmuller, Fischer,
Faujas, Home, and other learned men, whose works I have
quoted with much care in those chapters of my books to which
they relate.

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THE SURFACE OF THE GLOBE

particularly the whole carcases in the layers, betokens
either that the layer itself which contains them was
formerly dry land, or that there was terra firma in its
immediate vicinity. Their disappearance renders it
certain that this layer was inundated, or that this dry
land ceased to exist. It is then by these that we learn in
a positive manner the important fact of the repeated
irruptions of the sea, with which shells and other
marine productions could not have made us acquainted;
it is by studying them profoundly that we may hope to
ascertain the numbers and periods of these irruptions.
Secondly, the nature of the revolutions which have
altered the surface of the globe must have exercised a
more entire action over terrestrial quadrupeds than
marine animals. As these revolutions have in a great
measure consisted in changes of the bed of the sea, and
the waters must have destroyed all the quadrupeds
which they reached, if the irruption were general the
whole class must have perished; or, if only operating
on certain continents, it must have destroyed at least
the species peculiar to these continents, without
exercising the same influence upon marine animals. On
the contrary, millions of aquatic individuals might
have been left on dry land, or buried under new layers,
or thrown with violence on the shore; and their race be
still preserved in some places more tranquil, where it
might again be propagated after the disturbance of the
waters had ceased.
Thirdly, this action, as more complete, is more
easily seized on; it is more easy to demonstrate its
effects, because, the number of quadrupeds being
limited, the greater part of their species, at least of the
larger kind, being known, we have still farther

40

ON THE REVOLUTIONS OF

means afforded us of ascertaining whether the fossil
bones belong to one of them, or if they formed a part
of a species now extinct. As we are, on the contrary,
very far from knowing all the marine testacea and sea
fish; as we are probably ignorant yet of the greater
part which are in the depths of the ocean, it is
impossible to know with certainty if a species found
fossilized be or be not extinct. Thus we observe
learned men obstinately bent on giving the name of
pelagian shells, that is, shells of the deep sea, to
belemnites, to cornua-amonis, and other shelly relics,
which have as yet only been observed in ancient layers;
meaning by that, that if they have not been yet found
in a living state, it is because they inhabit depths
beyond the reach of our nets.

Certainly naturalists have not yet traversed every
continent, and do not even know all the quadrupeds
which inhabit the countries over which they have
travelled. New species of this class are from time to
time discovered; and those who have not attentively
examined all the circumstances of these discoveries,
might believe also that the unknown quadrupeds whose
bones are found in our layers have remained concealed
to the present time in some islands not yet discovered,
or in some of the vast deserts which occupy the middle
of Asia, Africa, the two Americas, and New Holland.

LITTLE PROBABILITY OF FINDING NEW SPECIES OF
GREAT QUADRUPEDS.

However, if we examine what species of quadrupeds
have been recently found, and in what