that we are able to trace those indications.

The material proximate causes (as they are termed,) of the production of organized life are causes of a different kind from that moral causation which, in the imposition of laws on matter, and in calling that matter into its existing combinations, we recognise as creative power.

Evidences of Creation.

JUST and sober inductive science, applied to the examination of the actual structure of the earth's crust, enables us with satisfaction and certainty to trace the changes which have taken place on the surface of a globe possessing the same nature as the existing earth, and in the structure and habits of organized beings analogous to those now inhabiting the world. It investigates the alterations which have been effected by physical agents resembling those now in operation, and in accordance with general laws the same as those now recognised in the economy of nature.

But it does not, and cannot rise to the disclosure of what occurred under a different state of things, or owing to the action of causes of a different order from those now discovered by physical research. It cannot show a chaos, or trace the evolution of a world out of it. It cannot reason upon a supposed state of universal confusion and ruin, and the immediate reduction of it into order and arrangement.

It can investigate the changes of things, but not their origin; in a word, sound geology will never aspire to the character of cosmogony.

Geology is, indeed, pre-eminently distinguished from other branches of physical science in this, that while they teach us only the existing order of nature, this carries us back in time, and shows a period when the present races of organized beings did not exist; and by consequence, establishes the fact of a creation, that is, more properly, of a series of creations; and these manifestly not brought about at any one marked period, or extending to all animated nature at once, but by the slow and gradual introduction of each new species as the older disappeared.

The successive strata are the sepulchres of successive races of organized beings, differing more or less from existing species; and those of the least antiquity containing extinct species, co-existent with those now tenanting the globe, and bearing decisive evidences of progressive, local, gradual deposition and elevation. The marks of sudden violence, indeed, are occasionally seen in all formations; but their occurrence is the exception, not the rule; and in its most extreme cases, always limited to a narrow local extent. No one simultaneous universal change has ever taken place on the surface of the globe; but all effects, however great, have been accomplished by a series of local and partial changes; and even where we may be left to conjecture as to the violence or suddenness of those changes with respect

to time, we have ocular proof of their extent in space. All that geology establishes, then, in this particular, is the fact of the gradual origination of new species, but by no means the particular method or process by which it has been brought about.

It is true there have not been wanting theories to explain these processes on natural principles. Yet of these, the most celebrated have failed to stand the test of increasing observation; while none, perhaps, have been altogether satisfactory or free from material objections. Physical research cannot bring us to any distinct idea of the nature of creation. If we consider the simple case of the introduction of a single new species, or even individual of a new species, there is an obvious limit imposed on our speculations. On the other hand, it is freely open to the physical inquirer to trace, as closely as possible, the secondary means, as far as the nature of the case admits; to investigate rigorously, for example, all the modifications which change of climate, domestication, crossing of breeds, &c., may produce. Such inquiries may be far from successful; they may lead only to some few imperfect conclusions utterly insufficient to ground any theory upon; but certainly this is the only course open to the inductive inquirer.

The question respecting the immutability of speeies, and the possibility of a transition from one into another; of such modifications as we observe in intermediate races being perpetuated; of new species being thus eventually introduced; with the

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various collateral topics which are involved in these inquiries, have all formed the subjects of anxious debate, and even of animated controversy, among physiologists. There has undoubtedly been a preponderance of evidence against the notion; and the high authority of Cuvier has been claimed as heading the phalanx of the opponents. Whilst on the other hand, Geoffroy St. Hilaire has spoken of the age of Cuvier" as approaching its termination, and the immutability of species as a conviction fast fading away from men's minds. All that I presume to observe on such a subject is this: that it is a question fairly open to philosophical discussion; and one which is at any rate the only avenue to a scientific solution of the problem. If natural science be ever able to conduct us to the knowledge of such a point, it must be by some such route as this. And we have no more reason to despair of its doing so in this case than in any of the other instances of philosophical discovery, which in a past age might have been pronounced as hopeless and visionary as some are now disposed to consider this. While we must also recollect that all the conclusions which have been deduced from the observed facts relating to the modifications of species are restricted by the condition of the short period of time during which their operation has been contemplated; and that we must admit as essentially influential the very different circumstances which might affect similar operations continued through unlimited periods of past duration.

The appeal to another kind of evidence, to knowledge derived from another source than that of physical inquiry conducted on the principles of established natural analogies, would merely transfer our inquiry out of the pale of physical science into that of moral authority, and would consequently divest it of all force in respect to the purpose of substantiating the great truths of natural theology. The proper conclusions of physical inquiry are to be directed only to the two simple points, the actual occurrence of successive originations of species, and the elucidation, as far as possible, of the secondary means by which those originations may have been brought about.

Geology, then, affords abundant proof of the fact that there was a time when the present races of organized beings did not exist, and consequently bears direct testimony to the occurrence of what we term creation; that is, the introduction of new species; as it does also of the previous introduction of a vast series of other species, of which it also shows the successive extinction. But the evidence is perfectly clear as to the gradual character of this introduction of species. Those now existing are found to have co-existed with others now extinct, as these did in their turn with those of older date, until we arrive at periods when whole genera and classes were entirely different. But at no period do we find an absence of organized life followed by a simultaneous universal production of it.