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CHAPTER IX.

Organic Remains.—Evidences derived from them.-Erroneous Theories of Continuous Stratification.-Diluvial Fossil Remains. Diluvial Origin of Coal.-Unfounded Theories on this Subject.-The Belgian Coal Fields.Tropical Productions in Polar Regions.-Buffon's Theory. -High Importance of the Evidence of Fossils.-Natural and unavoidable mode of Transport.—Instances in Proof.Buoyant nature of Bodies after Death. Rate at which they might have been Transported.-The thick-skinned Animals floated longest.

HAVING thus found a further corroboration of the truth of Scripture, in examining the appearances still existing on the general surface of the earth, we now come to the consideration of a most important part of the evidence, by which the record is still further supported, and in a still more remarkable degree: I mean, that of the fossil remains of animal and vegetable productions, so abundant in the secondary and diluvial formations. This most interesting part of our subject is much too extensive to be here entered upon at great length; but as many of the theories of Geology have been formed on the evidence of fossils, viewed under a false light, it becomes highly necessary to take a general view of the subject; and this general view may, perhaps, prove sufficient for our present general purpose: for it must be evident, that a

few facts, unequivocally proved, and supported both by reason, and by history, are of more value in leading to a just conclusion, than a thousand theories, however plausibly and ably composed, where both reason, and history, are directly contradicted.

The observations of the last half century, in various parts of the world, have served to give us a tolerably extensive view of this wide field for enquiry but when we consider, that Geology is but yet in its youth, and is only gradually rejecting the wild fancies of its more childish years; and, further, when we remember the comparatively few spots upon the surface of the whole earth, where we can have free access to a view of the interior structure of its upper strata, it may, perhaps, be worthy of admiration, that our knowledge is already so extensive as it is. As every day, however, adds to the number of ardent enquirers who bring in their stores of information, to add to the common stock, we may hope, in a short time, to obtain much more correct and certain data than we even yet possess, in order to secure the foundations of the whole structure, which have been, hitherto, but too generally laid in the sand.

In tracing the strata on the earth's surface, we discover, first, that no organic substances exist in the primitive rocks; nor do we meet with any marine remains, until we rise several

stages in the secondary strata. As we mount, however, towards the surface, the quantity of shells increases, in some of the strata, while in others they are almost entirely wanting, as we may observe is the case in the visible parts of the present seas: but as we approach still nearer to the surface, and examine the rocks and soils which were formed at the period of the Deluge, we find a vast increase in the fossil remains, and also a much greater variety in the species that have become embedded.

In the course of our examination into the laws of nature, by which secondary formations have been, and are still in the act of being formed, we found that it could not be expected that we should discover any fossil remains in the transition rocks, and but few in the earlier secondary formations; because, in the first case, the rocks so called, having been formed from the first fragments of the primitive earth, (by the depression of a part of which, the bed for the "gathering together of the waters" was first formed,) were arranged by the currents of the ocean, before that ocean became thickly peopled; and, in the second case, because the empty shells of the tribes, as they perished, would be comparatively few, for many years after the rivers, and the ocean, had been at work in forming secondary deposits. As time

advanced, however, the sea would naturally become loaded with the shelly remains of past generations; and we should, therefore, expect to find a proportioned increase, contained in the tenacious soils which have since been hardened into stone.

As we have seen that the laws which are in constant action in the waters, have a power of assorting, and arranging different materials, in different, and separate situations, we should expect to find shells more abundant in one formation, than in another; and as we now find recent beds of sea sand, of the most equal grain, and of vast extent, without almost a vestige of entire sea shells, we cannot be surprised, on finding that the same law had obtained in the early sand-stone formations, and that free-stone rocks are consequently, in general, destitute of these fossil remains; while the calcareous rocks, which, when soft and moist, must have been of a tenacious and muddy consistency, retain shells in extraordinary quantities. We have also found, that there was little probability of discovering the remains of either fish or quadrupeds in the gradually formed secondary rocks, because, in the case of such deposits, the dead of both classes must generally have been devoured by the voracious tribes of the sea, before they could have been covered up and protected.

It has been too long and too generally the custom with geologists to reason, upon the age of particular formations, from the nature of the fossils which they may be found to contain. We have thus arrived at many erroneous conclusions, with respect both to the actual age of our globe, and to the gradual production of new species in the animal kingdom. As the whole science of geology may be considered to be founded on the evidence of organic fossils, it is of the highest importance, on entering upon this subject, to endeavour to correct our evidence, before coming to a final conclusion. And it is, therefore, highly necessary to discover, whether the theory of continuous stratification is well founded; and also, whether a distinct identity of fossil species can, in general, be traced in the same formations, in every situation. On this most important part of the subject I cannot produce stronger reasoning than has already been made use of by one of our most distinguished writers on Geology and Mineralogy; and the author of the very able article on Organic Remains, in the Edinburgh Encyclopædia. Although my opinions, on many parts of these subjects, differ widely from those expressed by this able writer, yet we here so completely coincide, that I shall not hesitate to introduce his line of reasoning in this place.

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