species, introduced since the conclusion of the Tertiary Formation. It must now be owned that there are insurmountable objections to such an hypothesis. First, it is not true that the specific forms of the tertiary epoch have all of them disappeared. There are several-for example, a badger of the Miocene-which are not in the slightest degree distinguished from living species. Many reptiles, now living in India, have been proved to be coëval with the Himalayan Anoplothere, Mastodon, and Hippopotamus. Second, the specific distinctions alleged in a great number of cases between tertiary and existing animals are extremely slight, and such as we have no fixed principle by which to be assured that they mark new species, in the sense of a new creation. Finally, the tertiary animals of America indicate an approximation to the character of existing animals in that region, and tertiary animals of the other great continent equally approximate to those at present occupying it; showing that the demarcations of the present great zoological provinces had been already marked out, and have never been obliterated. There is therefore enough to justify us in believing that no entire submergence of the earth took place at the time of the Diluvium, though how nearly it might approach completeness we cannot say.

There are some other superficial formations, of less consequence on the present occasion than the diluvium—namely, lacustrine deposits, or filled-up lakes; alluvium, or the deposits of rivers beside their margins; deltas, the deposits made by great rivers at their efflux into the sea; peat mosses; and the vegetable soil. The animal remains found in these generally testify to a zoology on the verge of that now prevailing, or melting into it, there being included many species which still exist. In a lacustrine deposit at Market-Weighton, in the Vale of York, there have been found bones of the elephant, rhinoceros, bison, wolf, horse, felis, deer, birds, all or nearly all presenting peculiarities different from existing species, associated with thirteen species of land and fresh-water shells, "exactly identical with types now

living in the vicinity." In similar deposits in North America, are remains of the mammoth, mastodon, buffalo, and other animals of extinct and living types. In short, these superficial deposits show precisely such remains as might be expected from a time at which the present forms of the animal world had been generally assumed, but yet so far remote in chronology as to allow of the dropping of many species, through familiar causes-perhaps we should only say the obliteration of many peculiarities called specific-in the interval. Still, however, several of the most important living species have left no record of themselves in any formation beyond what are, comparatively speaking, modern. Such are the sheep and goat, and such, above all, is our own species. We thus learn that, compared with many humbler animals, man is a being, as it were, of yesterday.

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GENERAL CONSIDERATIONS

RESPECTING

THE ORIGIN OF THE ANIMATED TRIBES.

THUS concludes the wondrous section of the earth's history which is told by geology. It takes up our globe at an early stage in the formation of its crust; conducts it through what we have every reason to believe were vast spaces of time, in the course of which many superficial changes took place, and vegetable and animal life was gradually evolved; and drops it just at the point when man was apparently about to enter on the scene. The compilation of such a history, from materials of so extraordinary a character, and the powerful nature of the evidence which these materials afford, are calculated to excite our admiration, and the result must be allowed to exalt the dignity of science, as a product of man's industry and his reason.

It is now to be remarked, that there is nothing in the whole series of operations displayed in inorganic geology, which may not be accounted for by the agency of the ordinary forces of nature. Those movements of subterranean force which thrust up mountain ranges and upheaved continents, stand in inextricable connexion, on the one hand, with the volcanoes which are yet belching forth lavas and shaking large tracts of ground, as, on the other, with the primitive incandescent state of the earth. Those forces which disintegrated the early rocks, and of

the detritus formed new beds at the bottom of seas, are still seen at work to the same effect in every part of the globe. To bring these truths the more clearly before us, it is possible to make a substance resembling basalt in a furnace; limestone and sandstone have both been formed from suitable materials in appropriate receptacles; the phenomena of cleavage have, with the aid of electricity, been simulated on a small scale, and by the same agent crystals are formed. In short, the remark which was made regarding the indifference of the cosmical laws to the scale on which they operated, is to be repeated regarding the geological. A common furnace will sometimes exemplify the operation of forces which have been concerned in the production of a Giant's Causeway; and in a sloping ploughed field after rain, we may often observe, at the lower end of a furrow, a handful of washed and neatly deposited mud or sand, capable of serving as an illustration of the way in which Nature has produced the deltas of the Nile and Ganges. In the ripple-mark on sandy beaches of the present day, we see Nature's exact repetition of the operations by which she impressed similar features on the sandstones of the carbonigenous era. Even such marks as windslanted rain would in our day produce on tide-deserted sands, have been read upon tablets of the ancient strata. It is the same Nature that is to say, God through or in the manner of nature -working everywhere and in all time, causing the wind to blow, and the rain to fall, and the tide to ebb and flow, inconceivable ages before the birth of our race, as now. So also we learn from the conifers of those old ages, that there were winter and summer upon earth, before any of us lived to liken the one to all that is genial in our own nature, or to say that the other breathed no airs so unkind as man's ingratitude. Let no one suppose there is any necessary disrespect for the Creator in thus tracing his laws in their minute and familiar operations. There is in reality no true great and small, grand and familiar, in nature. Such only appear, when we thrust ourselves in as a point from which to start in judging. Let us pass, if possible, beyond

immediate impressions, and see all in relation to Cause, and we shall chastenedly admit that the whole is alike worshipful.

The Creator, then, is seen to have formed our earth, and effected upon it a long and complicated series of changes, in the same manner in which we find that he conducts the affairs of nature before our living eyes: that is, in the manner of natural law. This is no rash or unauthorized affirmation. It is what we deduce from the calculations of a Newton and a Laplace, on the one hand; and from the industrious observation of facts by a Murchison and a Lyell, on the other. It is a point of stupendous importance in human knowledge; here at once is the whole region. of the inorganic taken out of the dominion of marvel, and placed under an idea of divine regulation which we may endlessly admire and trust in.

Mixed up, however, with the geognostic changes, and apparently as a final object connected with the formation of the globe itself, there is another set of phenomena presented in the course of our history-the coming into existence, namely, of a long suite of living things, vegetable and animal, terminating in the families which we still see occupying the surface. The question arisesIn what manner has this set of phenomena originated? Can we touch at and rest for a moment on the possibility of plants and animals having likewise been produced in a natural way; thus assigning immediate causes of but one character for everything revealed to our sensual observation; or are we at once to reject this idea, and remain content, either to suppose that creative power here acted in a different way, or to believe unexaminingly, that the inquiry is one beyond our powers?

Taking the last question first, I would reply, that I am extremely loath to imagine that there is anything in nature which we should, for any reason, refrain from examining. If we can infer aught from the past history of science, it is, that the whole of nature is a legitimate field for the exercise of our intellectual faculties; that there is a connexion between this knowledge and our well-being; and that, if we may judge from things once despaired of by our

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