Essay on the Theory of the Earth, 1813

Georges Cuvier

• Publisher: Routledge
• Year: 2018
• ISBN:
  9781136977558
• Edition: 1
• Topic: History
• Subtopic: Ancient History
• Index: History

Based at the Parisian Museum of Natural History, Cuvier was able to compare the fossil bones he dug from the quarries of Montmartre with those of animals alive today. Guided by the principle of correlation, that all the parts of an animal must cohere, and by analogy, with living species, Cuvier boldly reconstructed extinct creatures from the incomplete skeletons he unearthed. This process is described in his Essay on the Theory of the Earth.

ESSAY
ON
THE THEORY OF THE EARTH.
======

§ 1. Preliminary Observations.

It is my object, in the following work, to travel over ground which has as yet been little explored, and to make my reader acquainted with a species of Remains, which, though absolutely necessary for understanding the history of the globe, have been hitherto almost uniformly neglected.

As an antiquary of a new order, I have been obliged to learn the art of decyphering and restoring these remains, of discovering and bringing together, in their primitive arrangement, the scattered and mutilated fragments of which they are composed, of reproducing, in all their original proportions and characters, the animals to which these fragments formerly belonged, and then of comparing them with those animals which still live on the surface of the earth; an art which is almost unknown, and which presupposes, what had scarcely been obtained before, an acquaintance with those laws which regulate the coexistence of the forms by which the different parts of organized beings are distinguished. I had next to prepare myself for these enquiries by others of a far more extensive kind, respecting the animals which still exist. Nothing except an almost complete review of creation in its present state, could give a character of demonstration to the results of my investigations into ita,ancient state; but that review has afforded me, at the same time, a great body of rules and affinities which are no less satisfactorily demonstrated; and the whole animal kingdom has been subjected to new laws in consequence of this Essay on a small part of the theory of the earth.*

The importance of the truths which have been developed in the progress of my labours, has contributed equally with the novelty of my principal results to sustain and encourage my efforts. May it have a similar effect on the mind of the reader, and induce him to follow me patiently through the difficult paths in which I am under the necessity of leading him !

The ancient history of the globe, which is the ultimate object of all these researches is also of itself one of the most curious subjects that can engage the attention of enlightened men; and if they take any interest in examining, in the infancy of our species, the almost obliterated traces of so many nations that have become extinct, they will doubtless take ‘a similar interest in collecting, amidst the darkness which covers the infancy of the globe, the traces of those revolutions which took place anterior to the existence of all nations.

We admire the power by which the human mind has measured the motions of globes which nature seemed to have concealed for ever from our view : Genius and science have burst the limits of space, and a few observations, explained by just reasoning, have unveiled the mechanism of the universe. Would it not also be glorious for man to burst the limits of time, and, by a few observations, to ascertain the history of this world, and the series of events which preceded the birth of the human race ? Astronomers, no doubt, have advanced more rapidly than naturalists; and the present period, with respect to the theory of the earth, bears some resemblance to that in which some philosophers thought that the heavens were formed of polished stone, and that the moon was no larger than the Peloponnesus; but, after Anaxagoras, we have had our Copernicuses, and our Keplers, who pointed out the way to Newton; and why should not natural history also have one day its Newton ?

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*This will be seen more at large in the extensive wort upon Comparative Anatomy, in which I have been employed for more than twenty-five years, and which I intend soon to prepare for publication.

§ 2. Plan of this Essay.

What I now offer comprehends but a few of the facts which must enter into the composition of this ancient history. But these few are important; many of them are decisive; and I hope that the rigorous methods which I have adopted for the purpose of establishing them, will make them be considered as points so determinately fixed as to admit of no departure from them. Though this hope should only be realised with respect to some of them, I shall think myself sufficiently rewarded for my labour.

In this preliminary discourse I shall describe the whole of the results at which the theory of the earth seems to me to have arrived. I shall mention the relations which connect the history of the fossil bones of land animals with these results, and the considerations which render their histoiy peculiarly important. I shall unfold the principles on winch is founded the art of ascertaining these bones, or, in other words, of discovering a genus and of distinguishing a species by a single fragment of bone,—an art on the certainty of which depends that of the whole work. I shall give a rapid sketch of the results to which my researches lead, of the new species and genera which these have been the means of discovering, and of the different strata in which they are found deposited. And as the difference between these species and the species which still exist is bounded by certain limits, I shall show that these limits are a great deal more extensive than those which now distinguish the varieties of the same species; and shall then point out how far these varieties may be owing to the influence of time, of climate, or of domestication.

In this way I shall be prepared to conclude that great events were necessary to produce the more considerable differences which I have discovered : I shall next take notice of the particular modifications which my performance should introduce into the hitherto received opinions respecting the primitive history of the globe ; and, last of all, I shall enquire how far the civil and religious history of different nations corresponds with the results of an examination of the physical history of the earth, and with the probabilities afforded by such examination concerning the period at which societies of men had it in their power to take up fixed abodes, to occupy fields susceptible of cultivation, and consequently to assume a settled and durable form.

§ 3. Of the first Appearance of the Earth.

When the traveller passes through those fertile plains where gently flowing streams nourish in their course an abundant vegetation, and where the soil, inhabited by a numerous popular tion, adorned with flourishing villages, opulent cities, and superb monuments, is never disturbed except by the ravages of war and the oppression of tyrants, he is not led to suspect that nature also has had her intestine wars, and that the surface of the globe has been much convulsed by successive revolutions and various catastrophes. But his ideas change as soon as he digs into that soil which presented such a peaceful aspect, or ascend, the hills which border the plain; they are expended, if I may use the expression, in proportion to the expansion of his view; and they begin to embrace the full extent and grandeur of those ancient events to which I have alluded, when he climbs the more elevated chains whose base is skirted by these first hills, or when, by following the beds of the descending torrents, he penetrates into their interior structure, which is thus laid open to his inspection.

§ 4. First Proofs of Revolutions on the Surface of the Globe.

The lowest and most level parts of the earth, when penetrated to a very great depth, exhibit nothing but horizontal strata composed of various substances, and containing almost all of them innumerable marine productions. Similar strata, with the same kind of productions, compose the hills even to a great height. Sometimes the shells are so numerous as to constitute the entire body of the stratum. They are almost every where in such a perfect state of preservation, that even the smallest of them retain their most delicate parts, their sharpest ridges, and their finest and tenderest processes. They are found in elevations far above the level of every part of the ocean, and in places to which the sea could not be conveyed by any existing cause. They are not only inclosed in loose sand, but are often incrusted and penetrated on all sides by the hardest stones. Every part of the earth, every hemisphere, every continent, every island of any size, exhibits the same phenomenon. We are therefore forcibly led to believe not only that the sea has at one period or another covered all our plains, but that it must have remained there for a long time, and in a state of tranquillity ; winch circumstance was necessary for the formation of deposits so extensive, so thick, in part so solid, and containing exuviae so perfectly preserved.

The time is past for ignorance to assert that these remains of organized bodies are mere lusus nature,—productions generated in the womb of the earth by its own creative powers. A nice and scrupulous comparison of their forms, of their contexture, and frequently even of their composition, cannot detect the slightest difference between these shells and the shells which still inhabit the sea. They have therefore once lived in the sea, and been deposited by it : the sea consequently must have rested in the places where the deposition has taken place. Hence it is evident that the basin or reservoir containing the sea has undergone some change at least, either in extent, or in situation, or in both. Such is the result of the very first search, and of the most superficial examination.

The traces of revolutions become still more apparent and decisive when we ascend a little higher, and approach nearer to the foot of the great chains of mountains. There are still found many beds of shells; some of these are even larger and more solid; the shells are quite as numerous and as entirely preserved; but they are not of the same species with those which were found in the less elevated regions. The strata which contain them are not so generally horizontal; they have various degrees of inclination, and are sometimes situated vertically. While in the plains and low hills it was necessary to dig deep in order to detect the succession of the strata, here we perceive them by means of the vallies which time or violence has produced, and which disclose their edges to the eye of the observer. At the bottom of these declivities, huge masses of their debris are collected, and form round hills, the height of which is augmented by the operation of every thaw and of every storm.

These inclined or vertical strata, which form the ridges of the secondary mountains, do not rest on the horizontal strata of the hills which are situated at their base, and serve as their first steps; but, on the contrary, are situated underneath them. The latter are placed upon the declivities of the former. When we dig through the horizontal strata in the neighbourhood of the inclined strata, the inclined strata are invariably found below. Nay, sometimes, when the inclined strata are not too much elevated, their summit is surmounted by horizontal strata. The inclined strata are therefore more ancient than the horizontal strata. And as they must necessarily have been formed in a horizontal position, they have been subsequently shifted into their inclined or vertical position, and that too before the horizontal strata were placed above them.

Thus the sea, previous to the formation of the horizontal strata, had formed others, which, by some means, have been broken, lifted up, and overturned in a thousand ways. There had therefore been also at least one change in the basin of that sea which preceded ours; it had also experienced at least one revolution; and as several of these inclined strata which it had formed first, are elevated above the level of the horizontal strata which have succeeded and which surround them, this revolution, while it gave them their present inclination, had also caused them to project above the level of the sea, so as to form islands, or at least rocks and inequalities; and this must have happened whether one of their edges was lifted up above the water, or the depression of the opposite edge caused the water to subside. This is the second result, not less obvious, nor less clearly demonstrated, than the first, to every one who will take the trouble of studying carefully the remains by which it is illustrated and proved.

§ 5. Proofs that such Revolutions have been numerous.

If we institute a more detailed comparison between the various strata and those remains of animals which they contain, we shall soon discover still more numerous differences among them, indicating a proportional number of changes in their condition. The sea has not always deposited stony substances of the same kind. It has observed a regular succession as to the nature of its deposits; the more ancient the strata are, so much the more uniform and extensive are they; and the more recent they are, the more limited are they, and the more variation is observed in them at small distances. Thus the great catastrophes which have produced revolutions in the basin of the sea, were preceded, accompanied, and followed by changes in the nature of the fluid and of the substances which it held in solution; and when the surface of the seas came to be divided by islands and projecting ridges, different changes took place in every separate basin.

Amidst these changes of the general fluid, it must have been almost impossible for the same kind of animate to continue to live :—nor did they do so in fact Their species, and even their genera, change with the strata; and although the same species occasionally recur at small distances, it is generally the case that the shells of the ancient strata have forms peculiar to themselves; that they gradually disappear, till they are not to be seen at all in the recent strata, still less in the existing seas, in which, indeed, we never discover their corresponding aperies, and where several even of their genera are not be found ; that, on the contrary, the shells of the recent strata resemble, as it respects the genus, those which still exist in the sea; and that in the last-formed and loosest of these strata there are so...

Table of contents

• Cover Page
• Half Title
• Title Page
• Copyright Page
• Dedication
• Preface
• Contents
• 1. PRELIMINARY Observations
• 2. Plan of this Essay
• 3. Of the first Appearance of the Earth
• 4. First Proofs of Revolutions on the Surface of the Earth
• 5. Proofs that such Revolutions have been numerous
• 6. Proofs that the Revolutions have been sudden
• 7. Proofs of the Occurrence of Revolutions before the Existence of Living Beings
• 8. Examination of the Causes which act at present on the Surface of our Globe
• 9. Of Slips, or Falling Down of the Materials of Mountains
• 10. Of Alluvial Formations
• 11. Of the Formation of Downs
• 12. Of the Formation of Cliffs, or steep Shores
• 13. Of Depositions formed in Water
• 14. Of Stalactites
• 15. Of Lithophytes
• 16. Of Incrustations
• 17. Of V olcanoes
• 18. Of Astronomical Causes of the Revolutions on the Earth’s Surface
• 19. Of former Systems of Geology
• 20. Diversities of the Geological Systems, and their Causes
• 21. Statement of the Nature and Conditions of the Problem to be solved
• 22. Of the Progress of Mineral Geology
• 23. Of the Importance of Extraneous Fossils, or Petrifactions, in Geology
• 24. High Importance of investigating the Fossil Remains of Quadrupeds
• 25. Of the small Probability of discovering new Species of the larger Quadrupeds
• 26. Enquiry respecting the Fabulous Animals of the Ancients
• 27. Of the Difficulty of distinguishing the Fossil Bones of Quadrupeds
• 28. Results of the Researches respecting the Fossil Bones of Quadrupeds
• 29. Relations of the Species of Fossil Bones, with the Strata in which they are found
• 30. Proofs that the extinct Species of Quadrupeds are not Varieties of the present existing Species
• 31. Proofs that there are no Human Bones in the Fossil State
• 32. Proofs of the recent Population of the World, and that its present Surface is not of very ancient Formation
• 33. Proofs, from Traditions, of a great Catastrophe, and subsequent Renewal of Human Society
• 34. Proofs derived from several miscellaneous Considerations
• 35. Concluding Reflections
• SUPPLEMENT, being an extract from the Researches of M. de Prony, on the Hydraulic System of Italy: containing an Account of the Displacement of that Part of the Coast of the Adriatic which is occupied by the Mouths of the Po
• APPENDIX, containing Mineralogical Notes, and an Account of Cuvier’s Geological Discoveries