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as are to be met with on the coasts of New Holland.
We can have a clear idea of them from the description
given by Péron.(1)


When, on the contrary, the coast is lofty, the sea,
which can deposite nothing, is perpetually destroying:
its waves wear away the bank, and destroy the summit,
because the higher parts, being left without
foundation, are incessantly falling away into the sea,
where they are tossed about by the waves until the
softer and looser particles are lost. The harder
portions, by dint of continued friction form those
round pebbles, or that accumulated strand which serves
to strengthen the base of the steeps.
Such is the action of the waters on terra firma,
which consists only in small levellings, and those not
indefinite. The falling materials of the mountain tops
into the valleys; their particles, those of the hills and
plains, conveyed to the sea; the alluvial deposites
extending the coasts at the expense of the heights, —
are the limited effects which vegetation has in some
degree put a boundary to; which suppose, besides the
pre-existence of mountains, valleys in short, of all the
inequalities of the globe, and which consequently
could not themselves have produced those inequalities.
The downs are a still more limited phenomenon, both
in height and horizontal extent; they have no relation
to those enormous masses into the origin of which
geology seeks to penetrate.
As to the operation of the waves in their own

(1) In his 'Voyage aux Terres Australes.'



although we cannot accurately ascertain it, yet we can
to a certain extent point out its effects.


Lakes, ponds, marshes, and sea-ports into which
streams flow, particularly when issuing from
neighbouring and rugged hills, deposite at their bottom
shoals of mud, which would in time choak them up, if
constant care was not taken to cleanse them; the sea
also leaves in harbours, creeks, and all parts where its
waters are most calm, mud and sediment. Currents are
formed amongst these deposites, or throw upon them
the sand which they collect from the sea; and thus are
shoals and shallows made.


Certain waters, after depositing the calcareous
substances, by means of the superabundant carbonic
acid with which they are impregnated, become
crystallized when the acid has evaporated, and form
stalactites and other concretions. There are mingled
crystallized layers in soft water, sufficiently extensive
to be compared with some of those left by the ancient
sea. Every one knows the famous Travertine quarries
in the vicinity of Rome, and the rocks of this stone
which the river Teverona accumulates and, produces,
perpetually varying in form. Its twofold action may be
thus accounted for: the accumulated deposites of the
sea may become hardened by stalactites; when,
perhaps, springs replete with calcareous matter, or
containing some other substance in solution, fall into
the places where these



masses are formed, and then become a combination
formed by the union of the marine deposites with the
fresh water. Such are the banks of Guadeloupe, which
contain marine and terrestrial shells and human
skeletons. Such, also, is the quarry near Messina,
described by Saussure, where the sandstone is produced
by the sands cast up by the sea, and which there


In the torrid zone, where litophytes are numerous in
species and propagate rapidly, their stony columns are
formed into rocks, reefs, &c.; and, reaching to the
level of the waves, block up the entrance of the ports,
and are the destructive foes of navigation. The sea
casting sand and slime on the top of these rocks,
frequently raises their surface above the proper level,
and thus generates islands which soon exult in rich


It is possible, also, that in certain places shell-fish
leave their testaceous coverings, which, amalgamated
with slime more or less concreted, or with some other
cements, form extensive deposites, or a kind of shelly
reef; but we have no evidence that the sea at present
can incrust these shells with a paste as solid as marble,
sand-stone, and even the compact limestone in which
we see the shells of our layers

(1) See Forster's 'Observations on the South Sea.'



embedded. Still less do we find that it deposites any
portion of those more solid and more flinty layers
which preceded the formation of shell-reefs.
All these causes united would not perceptibly affect
the level of the sea, would not raise a single layer
above that level, and assuredly would not produce the
least hillock on the surface of the earth. It has been
asserted, with some appearance of probability, that the
sea gradually decreases, and that observations to that
effect have been made on the shores of the Baltic.(1)
But whatever may be the causes of these variations, it
is certain that they are not universal; that in the
greatest number of ports, where there are so many
persons interested in observing the height of the sea,
and when fixed and ancient works afford so many
means of computing these variations, the mean level is
constantly the same; there is no general sinking; there
is no universal encroaching. In other places, as
Scotland and various parts in the Mediterranean, they
have supposed, on the contrary, that the sea has
become higher, and now covers shores formerly above
its level. (2)

(1) It is a prevalent opinion in Sweden, that the sea lowers,
and that we can ford or even walk dry-shod in many places
where formerly it was impassable. Very learned men have
espoused this popular idea, and to so great an extent is M. de
Bach imbued with it, that he supposes that gradually the whole
soil of Sweden will become dry land. But it is singular that no
regular and precise observations to confirm a theory broached
so long, have been made, and made public, which would leave
no doubt, if, as Linnæus says, this difference of level be as
much as four or five feet annually.
(2) Mr. B. Stevenson, in his observations on the bed of the
North Sea, and the British Channel, asserts that the level of
these seas has become constantly and sensibly higher during
the last three centuries. Fortis says the same thing of certain
places in the Adriatic; but the example of the temple of
Serapis, near Pozzuola, proves that the borders of this sea are
in many places of a nature occasionally to elevate themselves




The action of volcanoes is still more limited and
more locally confined than any others which we have
adverted to. Although we have no clear idea of the
means by which nature feeds these fierce furnaces at
depths so profound, we yet judge clearly, by their
effects, of the alterations which they have occasioned
on the earth's surface. When a volcano appears, after
some shocks, some earthquakes, it finds an opening.
Stones and ashes are thrown far and wide; lava is
vomited forth; the more fluid portion glides away in
long streams; the more solid is stopped at the edges of
the aperture which it serves to elevate, and forms a
cone terminated by a crater. Thus volcanoes
accumulate on the surface, (after having in a measure
modified them,) materials before buried in the depths
of the earth; they form mountains; they have in earlier
ages covered some parts of our continents with them;
they have suddenly produced islands in the midst of
the ocean; but these mountains, these islands are
always composed of lava, all their materials have
under gone the action of fire; they are distributed as
materials must be which emanate from an elevated
spot. Volcanoes do not elevate, nor overthrow the
layers which lie along their apertures; and if certain
causes have operated from their abysses, and assisted
in overthrowing vast mountains, it has not been

and sink again. But, on the other hand, there are thousands of
quays, roads, and other places made along the coast by the
Romans, from Alexandria to Belgium, the relative level of
which has never altered.



by means of volcanic agents of which we have any
Thus, we repeat, it is in vain to seek amidst the
forces now acting on the surface of the earth, for
causes sufficiently powerful to produce the revolutions
and catastrophes of which its exterior bears traces; and
if we have recourse to the external causes at present in
action, we shall not find them adapted for the purpose.


The pole of the earth moves in a circle about the
pole of the ecliptic; its axis inclines more or less
according to the ecliptic; but these two motions (which
are well understood) are performed within known
directions and limits, and have no proportion to the
effects, the extent of which we have just considered. In
every instance, their extreme slowness would preclude
the idea that they had any influence on the catastrophe
which we have proved to be violent and sudden.
This latter reason is applied to all the slow agencies
that have been imagined, doubtlessly, in the hope that
their existence could not be denied, because it would
be always easy to assert that their tardiness made them
imperceptible. True, or not, is of little consequence;
they explain nothing, for no slow causes can produce
sudden results. There may have been a gradual
diminution of the waters, the sea may have conveyed
every kind of solid matter, the temperature of the
globe may have increased or diminished, but none of
them have been the agents which have disturbed our
layers, which have clothed with ice great quadrupeds



with their flesh and skin; which have thrown on dry
land those testaceous remains, still as perfect as if they
contained living fish; which have, in fine, destroyed
whole species and genera.
These arguments have struck the majority of
naturalists: and amongst those who have sought to
explain the present state of the globe, there is scarcely
one who has attributed it entirely to slow causes, still
less to causes operating before our eyes. The necessity
they have experienced of discovering different causes
from those now in action has given rise to many
extraordinary speculations, and has involved them in
so many and so contrary suppositions, that the very
name of their science has been long a subject of
raillery for some prejudiced persons, who only look at
the various systems that have been broached, and
forget, or are ignorant of the long and important series
of positive facts that have been developed. (1)


For a long time only two events, only two changes
of the globe, have been admitted — the creation and
the deluge; and all the labours of geologists have
tended to explain the present state, by imagining a
certain primitive state, afterwards modified by the
deluge, and to which each speculist assigned his own
causes, action, and effects.
Thus, according to one,(2) the earth at first had

(1) When I say this, I announce a fact daily proved, but I
have not pretended to express my own opinion, as some
geologists have thought. As some ambiguity in my speech has
given rise to the error, I must apologize or it.
(2) Burnet Telluris Theoria Sacra. 1681.



an equal and light crust which covered the abyss of
waters, and which burst to produce the deluge; its
relics formed the mountains. According to another,(1)
the deluge was occasioned by a momentaneous
suspension of the cohesion in minerals; the whole mass
of the globe was dissolved, and the paste of it was
penetrated by shells. According to a third,(2) God
lifted up the mountains to allow the waters, which
produced the deluge, to escape; and removed them to
the places where there were more stones, because
otherwise they could not have been supported. A
fourth (3) created the earth with the atmosphere of one
comet, and deluged it through the tail of another; the
heat which remained to it from its first origin excited
all mankind to sin; thus they were all drowned except
the fishes, which had apparently passions less unruly.
We see, that, even in confining ourselves to the
limits fixed by Genesis, naturalists have a wide field
before them: they soon found themselves in
difficulties, and when they had succeeded in
attributing to the six days of creation indefinite
periods, ages costing them nothing, their systems took
a flight proportioned to the intervals which they could
dispose of.
The great Leibnitz amused himself, like Descartes,
in making the earth a quenched sun, (4) a vitrified
globe, on which vapours having fallen at the time of
its extinction, seas were formed, which in their turn
deposited calcareous formations.

(1) Woodward's Essay towards the Natural History of the
Earth. 1702.
(2) Scheuchzer, Mem. de l'Acad. 1708.
(3) Whiston. A New Theory of the Earth. Lond. 1708.
(4) Leibnitz, Protogæa. Act. Leips. 1683. Gott. 1749



Demaillet covered the whole globe with water for
thousands of years; he caused those waters gradually to
retire; all terrestrial animals had at first been marine;
man himself was at first a fish; and the author assures
his readers that it is not uncommon to find in the
ocean fishes which have only become half men, but
which will some day become entire human beings. (1)
The system of Buffon is only a development of that
of Leibnitz, with the sole addition of a comet, which
produced from the sun, by a violent shock, the
liquefied mass of the earth, together with all the
planets: whence result his positive data, for by the
actual temperature of the earth we can calculate how
long a time has elapsed since it grew cool; and, since
the other planets came from the sun at the same time as
the earth, we may reckon how many ages must elapse
before the larger ones cool, and to what extent the
smaller ones have become refrigerated. (2)


In our times imagination has exercised itself with
more freedom than before on this important subject.
Some writers have reproduced and greatly extended the
ideas of Demaillet; they say, that at first, every thing
was in a state of liquefaction; that the liquid at first
engendered animals of the simplest kind, such as
monads and others of the infusory and microscopic
species, that in the progress of time, and in assuming
different habits, the animalia complicated and
diversified their species to the extent which we now
have in existence. It is these animals who have
converted the waters

(1) Telliamed. Amster. 1748.
(2) Théorie de la Terre, 1749; et Epoques de Ia Nature, 1775.



of the ocean gradually into calcareous earth;
vegetables, on the origin and changes of which they
tell us nothing, have changed the water into clay; but
these two earths, by dint of being deprived of the
characteristics which life had impressed on them, were
resolved, by the last analysis, into flint; and that is the
reason why the oldest mountains are the most flinty.
All the solid portions of the earth owe their birth,
then, to life, and without life the whole globe would
be still wholly liquid. (1)
Other writers have given the preference to the
theory of Kepler. Like this great astronomer, they
assign vital powers to the globe; they say that a fluid
circulates around it; an assimilation is made as in
animate bodies; each of its component parts has life:
not only the very elementary atoms have instinct and
will, which attract and repel by sympathies and
antipathies: but every sort of mineral can convert
immense masses into its own proper nature as we
convert our aliments into flesh and blood. Mountains
are the organs of the respiration of the globe, and the
schists the secreting organs; it is by these that sea
water is decomposed to engender volcanic eruptions;
the veins in mines are the caries, the abscesses, of the
mineral kingdom; and the metals a production of
putrefaction and disease; and this accounts for their
bad smell. (2)
Still more recent is a philosophy which substitutes
metaphors for reasoning, setting out with a

(1) See La Physique de Rodig. p. 106. Leips. 1801; and p.
169, vol. ii. of Telliamed, as well as a great number of German
works. M. de Larnark has, with much research and talent
developed this system in his 'Hydrogeology and Zoological
(2) M. Patrin has shown much imagination in supporting
these fantastic ideas, in many articles in 'Le Nouveau
Dictionnaire d'Histoire Naturelle.'

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