organic remains, would be no less absurd than to undertake to write the history of any ancient people, without reference to the documents afforded by their medals and inscriptions, their monuments, and the ruins of their cities and temples. The study of Zoology and Botany has therefore become as indispensable to the progress of Geology, as a knowledge of Mineralogy. Indeed the mineral character of the inorganic matter of which the Earth's strata are composed, presents so similar a succession of beds of sandstone, clay, and limestone, repeated irregularly, not only in different, but even in the same formations,[1] that similarity of mineral composition is but an uncertain proof of contemporaneous origin, while the surest test of identity of time is afforded by the correspondence of the organic remains: in fact without these, the proofs of the lapse of such long periods as Geology shows to have been occupied in the formation of the strata of the Earth, would have been comparatively few and indecisive.
The secrets of Nature, that are revealed to us, by the history of fossil Organic Remains, form perhaps the most striking results at which we arrive from the study of Geology. It must appear almost incredible to those who have not minutely attended to natural phenomena, that the microscopic examination of a mass of rude and lifeless limestone should often disclose the curious fact, that large proportions of its substance have once formed parts of living bodies. It is surprising to consider that the walls of our houses are sometimes composed of little else than comminuted shells, that were once the domicile of other animals, at the bottom of ancient seas and lakes.
It is marvellous that mankind should have gone on for
- ↑ The same formation which in England constitutes the argillaceous deposites of the London Clay, presents at Paris the sand and freestone of the Calcaire Grossier; whilst the resemblance of their Organic remains proves the period of their deposition to have been the same, notwithstanding the difference in the character of their mineral ingredients.
