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belong to the same age or period of formation in the chronological order of the strata.
Fossils reveal to us the important and wonderful fact, that the Author of Nature had created different species of animals and plants, at successive and widely distant intervals of time, and that many of those, that existed in the earlier ages of our globe, had become totally extinct, before the creation of others in later periods: that, prior to man being called into existence, innumerable species of living beings had covered the surface of the earth, for a series of ages, to which we are unable, and probably shall ever remain unable, to fix any definite limits. We further learn, that a very large proportion of those creatures, of the later periods, had become extinct, and had been replaced by the animals which now exist, before the creation of our first parents. When that great event took place, the crust of the earth had already undergone numerous changes, and we have already said, in alluding to those changes, that they appear to us to afford indisputable proofs of design; to be evidences most clear of the establishment of an order of things adapted to the predetermined nature of that more perfect creature, about to be sent as an inhabitant of the globe, to whom was to be given "dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth." We are also taught by the study of fossils, that, prior to the creation of man, there had existed a totally different condition of our planet, in so far as regards the distribution of land and water, from that which now exists; that where there are now vast continents, there must have been deep seas, and that extensive tracts of land must have occupied those parts of the globe, which are now covered by the ocean. In many parts of the interior of our continents, there must have been vast lakes of fresh water, which were drained by subsequent changes in the form of the land which bounded them, and were replaced by wide valleys, long antecedent to the existence of man. Thus, in the very heart of France, in a district along
the banks of the river Allier, of which the town of Vichy may be taken as the centre, vast strata, full of fresh-water shells, prove, that there must have existed, for many ages, a lake nearly a hundred miles long, and twenty miles in average breadth. It is proved, moreover, by the nature of organic remains, that changes of CLIMATE, no less remarkable, have taken place; and that a heat equal to that now existing in the equatorial regions must have formerly prevailed in latitudes far north of our islands.
All this, so far from contradicting the Scriptures, confirms the Mosaic account of what is usually called the Creation. Moses says, In the beginning God created the heavens and the earth. How long that beginning was before the time that he wrote, he does not furnish us with the means of ascertaining; but he goes on to say, that the earth was without form and empty. All living beings, that might have been upon it previously, had been destroyed: it was in darkness and covered with water. When it was in this condition, which is usually called chaos, God said, Let there be light; and there was light; and thus the creation was commenced; for it is immediately added, that the morning and the evening were the first day.
The organized bodies which are found in a fossil state, belong to classes of animals and plants that exist on the land, or in lakes and rivers, and to those also, which are inhabitants of the sea. The latter are by far the most numerous, as might be expected would be the case, when it is considered, that the greater proportion of the strata must have been deposited at the bottom of the ocean. Of marine productions, shells and corals constitute the chief part, and for this reason, that being almost wholly composed of mineral substance, they are not liable to decay. In all cases of petrified remains of animals, it is the hard parts only that we find; the whole of the flesh and softer parts have disappeared, so much so, that, with the exceptions of some instances of fishes and amphibious animals, no trace of the external form of the living animal can be discovered; and
where bones are found, it is very rarely that an entire skeleton is met with. There are fossil remains of
These several bodies are not found indiscriminately throughout the whole series of the secondary and ter tiary strata; some are peculiar to the lowest beds, some to the intermediate, and some to the superior. But all, of whatever description they may be, which occur in the secondary strata, belong to species now wholly extinct. By far the greatest proportion of those found in the tertiary strata, belong likewise to extinct species. It is only in the uppermost beds that there is any very considerable number of individuals, which are identical with animals now in existence; and there they preponderate over the others.
The bones of man are not more liable to decay than those of other animals; but in no part of the earth, to which the researches of geologists have extended, has there been found a single fragment of bone, belonging to the human species, incased in stone, or in any of those accumulations of gravel and loose materials which form the upper part of the series of strata. Human bones have been occasionally met with in stones formed by petrifying processes now going on, and in caves, associated with the bones of other animals;
but these are deposits possessing characters which prove them to have been of recent origin, as compared with even the most modern of the tertiary strata.
The geologist may be considered as the historian of events relating to the animate and inanimate creation, previous to that period when sacred history begins, or the history of man, in relation to his highest destiny. Although it belongs to the geologist to study the events that have occurred within his province during the more modern ages of the world, as well as those which are in progress in our own day, his special object is to unfold the history of those revolutions, by which the crust of the globe acquired its present form and structure. The solid earth, with its stores of organic remains, which now rises above the surface of the sea, may be compared to a vast collection of authentic records, which will reveal to man, as soon as he is capable of rightly interpreting them, an unbroken narrative of events, commencing from a period indefinitely remote, and which, in all probability, succeeded each other after intervals of vast duration. Unlike the records of human transactions, they are liable to no suspicion that they may have been falsified through intention or ignorance. In them, we have to fear neither dishonesty nor the blunders of unlettered and wearied transcribers. The mummies of Egypt do not more certainly record the existence of a civilized people in remote ages on the banks of the Nile, than do the shells, entombed in solid stone at the summit of the Alps, and Pyrenees, attest that there was a time, when the rocks of those mountains occupied the bottom of a sea, whose waters were as warm as those within the tropics, and were peopled by numerous species of animals, of which there does not now exist one single descendant.
Some scattered observations, and some fanciful theories founded upon them, show that a few of the philosophers of antiquity, and a few among the learned since the revival of letters, were not altogether unaware of the existence of these archives; but it is little more than half a century since their true value began to be.
understood. The cause of this is easily explained. Geology has grown out of the advanced state of other branches of knowledge. Until chemistry, mineralogy, botany, and above all, zoology, or the natural history and comparative anatomy of animals, had arrived at a considerable degree of perfection, it was impossible to comprehend the language in which these records are written. Many of the early geologists, and some even in the present day, appear indeed to find no difficulty in reading them; and when they meet with a passage which is obscure, they cut the knot, and reason upon some bold interpretation, which they arrive at by conferring upon Nature, powers which she herself has never revealed to us that she has employed. But since the discovery, in recent times, by Cuvier and others, of a key to the language of these precious documents, many have been unrolled; the errors of former interpretations have been discovered; and we may now entertain a well-grounded hope, that if we cease to guess at meanings, and patiently search and compare the materials that are accessible to us, we shall arrive at such sound conclusions, that geology will be placed on as secure a basis as the most exact of the sciences.
We find in the lowest beds of the series of the secondary strata, that the organic remains consist chiefly of corals and shells, that is, of animals having a comparatively simple anatomical structure; and that as we ascend in the series, the proportion of animals of more complicated forms increases, the bones of land quadrupeds being almost entirely confined to the more