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Essay on the Theory of the Earth

Chapter 51: General Conclusion relative to the Period of the last Revolution.
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The essay assembles geological observations and fossil evidence to reconstruct Earth's successive changes, arguing that strata and petrified remains record numerous abrupt revolutions of the surface that caused mass extinctions and replacement of faunas. It examines how current agencies—erosion, slips, alluvial deposition, coastal cliffs, stalactites, lithophyte growths, incrustations, and volcanic activity—operate, and distinguishes their slow effects from the sudden events inferred in the rock record. It uses stratigraphic sequences and fossil assemblages to date relative episodes and to argue that many major revolutions preceded the appearance of existing life forms, offering a systematic account of Earth's physical and organic history.

General Conclusion relative to the Period of the last Revolution.

I agree, therefore, with MM. Deluc and Dolomieu, in thinking, that if any thing in geology be established, it is, that the surface of our globe has undergone a great and sudden revolution, the date of which cannot be referred to a much earlier period than five or six thousand years ago; that this revolution overwhelmed and caused to disappear the countries which were previously inhabited by man, and the species of animals now best known; that, on the other hand, it laid dry the bottom of the last sea, and formed of it the countries which are at the present day inhabited; that it is since the occurrence of this revolution that the small number of individuals dispersed by it have spread and propagated over the newly exposed lands, and, consequently, that it is since this epoch only, that human societies have assumed a progressive march, that they have formed establishments, raised monuments, collected natural facts, and invented scientific systems.

But the countries which are at present inhabited, and which the last revolution laid dry, had already been previously inhabited, if not by men, at least by land animals, and, therefore, one preceding revolution at least had put them under water; and if we may judge by the different orders of animals the remains of which are observed in them, they had perhaps been subjected to two or three irruptions of the sea.