Читать книгу Essay on the Theory of the Earth - Georges baron Cuvier - Страница 27

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To quit the language of mathematics, it may be asserted, that almost all the authors of these systems, confining their attention to certain difficulties which struck them more forcibly than others, have endeavoured to solve these in a manner more or less plausible, and have left unnoticed others, equally numerous, and equally important. For example, the only difficulty with one consisted in explaining the changes that had taken place in the level of the sea; with another, it consisted in accounting for the solution of all terrestrial substances in one and the same menstruum; and with a third, in shewing how animals that were believed to be natives of the torrid zone could live in the frigid zone. Exhausting all the powers of the mind upon these questions, they conceived that they had done every thing that was necessary when they had contrived some method of answering them; and yet, while they neglected all the other phenomena, they did not always think of determining with precision the measure and limits of those which they had endeavoured to explain.

This is peculiarly the case with regard to the secondary formations, which constitute, however, the most important and most difficult part of the problem. During a long time, all that was done with respect to these, consisted of feeble attempts to determine the order of superposition of their strata, and the connections of these strata with the species of animals and plants whose remains they contain.

Are there certain animals and plants peculiar to certain strata, and not found in others? What are the species that appear first in order, and what those which succeed? Do these two kinds of species sometimes accompany each other? Are there alternations in their appearance; or, in other words, do the first reappear a second time, and do the others then disappear? Have these animals and plants all lived in the places where their remains are found, or have they been transported thither from other places? Do they all live at the present day in some part of the earth, or have they been partially or totally destroyed? Is there any constant connection between the antiquity of the strata and the resemblance, or non-resemblance, of the fossils contained in them to the animals and plants which now exist? Is there any connexion, in regard to climate, between the fossils and such living beings as resemble them most? May it be concluded, that the transportation of these living beings, if such a thing ever happened, has taken place from north to south, or from east to west; or were they irregularly scattered and mingled together; and can the epochs of these transportations be determined by the characters which they have impressed upon the strata?

What can be said regarding the causes of the existing state of the globe, if no reply can be made to these questions,—if there be no sufficient grounds to determine the choice between answering in the affirmative or negative? It is but too true, that, for a long time, none of these points was satisfactorily determined; and scarcely even would geologists seem to have had any idea of the propriety of clearing them up before constructing their systems.