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It can scarcely, we think, be denied that the facts above enumerated point to something very like a progressive developement of organic life; though they will not support the doctrine to the extent contended for a few years ago, and though the terms in which it was announced might be open to objection. It is possible to repudiate the monstrous and absurd notions of Lamarck, respecting the transmutation of one species into another,-it is possible to admit that fishes, reptiles, and mammalia occur, respectively, in older strata than was supposed at the time Sir Humphry Davy wrote his Consolations in Travel,—we may admit the absence from the coal strata of fungi, lichens, and mosses, which are the simplest forms of flowerless vegetation, and the presence of ferns and Lycopodiaceæ, which are the most highly organized of the cryptogamic* plants, we may admit that the monocotyledonst of the same period consisted of the most highly-developed of that class of plants, and that it was not destitute of its dicotyledons.. It

may be true that an orthoceratite or a nautilus, though they have no back-bone, are, for the purposes for which they were designed, as perfect in their organization as an elephant or a crocodile; and that palms and bread-corn, though they have but one seed-lobe, are not inferior in dignity to an oak and a nettle which have two: and yet, admitting all this, we may contend with Professor Sedgwick, that a doctrine may be abused and yet contain the elements of truth,—that it is one thing to refute it, and another to point out the errors and overcharged statements of its supporters. “With reference," he says "to the functions of the individual, one organic structure is as perfect as another; but I think that in the repeated, and almost entire, changes of organic types in the successive formations of the earth,-in the absence of mammalia in the older, and their rare occurrence (and then in forms entirely unknown to us) in the newer secondary groups,-in the diffusion of warm-blooded quadrupeds (frequently of unknown genera) through the older tertiary systems,-in their abundance (and frequently of known genera) in the upper portion of the same series,—and, lastly, in the recent appearance of man on the surface of the earth, now universally admitted, -in one word, from all these facts combined we have a series of proofs, the most emphatic and convincing, that the existing order of Nature is not the last of an uninterrupted succession of mere physical events, derived from causes now in daily operation, but on the contrary, that the approach to the present system has been gradual, and that there has been a progressive developement of organic structure, subservient to the purposes of life 8."

While these changes were taking place in the organic world, changes as great were taking place in the inorganic. Land was converted into sea, and sea into land, and land again into sea. The same portions of the earth's surface have been subject to repeated oscillations, so as to be alternately above and below the ocean level. We have already alluded to the indications of a change of climate, discoverable in the crust of the globe. We shall not at present enter into a detail of all the evidence on which this rests; suffice it to say, that from the testimony of the imbedded organic remains, it appears that, during the formation of the

* Plants whose fructification is concealed. # Plants having two seed-lobes. + Plants having only one seed-lobe. S Sedgwick's Anniversary Address.

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older strata, a tropical, if not an ultra-tropical, climate prevailed over the northern hemisphere, and that even at a period so comparatively recent as the commencement of the tertiary series, a very high temperature existed over what are now the cool regions of Europe; when a great part of England was yet beneath the waves, when her mountain-chains formed a cluster of spice islands, haunted by the crocodile and the turtle, and when, on the spot where London now stands, the nautilus of the tropics, spreading his sail to the breeze, was the only representative of the fleets that crowd her port. But if the earth's crust furnishes us with evidence, that great and repeated changes have taken place in the organic and inorganic world, it furnishes us with proofs no less clear, that great epochs of time elapsed while these changes were in progress, epochs so great that we are tempted to connect them with the secular periods of astronomy to which we have before alluded. There is, however, this difference between the phenomena of astronomy and geology; that in the former we have a series of events recurring, in a fixed order, after the lapse of fixed intervals of time, whereas in geology (if we except the interchange between land and sea, and the recurrence of volcanic action after long intervals of repose) we have no evidence of the repetition of a single phenomenon, much less have we evidence of geological cycles, in which the same events are repeated, again and again, in a stated order, and at stated intervals. We have proofs of a change from a hot to a colder climate; but we have no proofs of a change from a cold climate to a hotter. Whole orders of fishes characteristic of the older strata become extinct, and are succeeded by new races, which in their turn give place to others. This class of vertebrated animals affords an unbroken record, from the earliest to the most recent geological epoch, and the changes which occur in it are more rapid than those which take place among invertebrate animals; but, as we ascend in the series of strata, we meet with no instance of the revival of any of the extinct genera or species. By means of a series of geological monuments, we can trace the commencement and decay of the family of the Ichthyosauri; but once extinct they reappear no more, except in the humorous sketch of Mr. Delabeche*: and, lastly, man becomes an inhabitant of the earth, but there is not a particle of evidence that the race had previously existed, though at some very remote period, and had been destroyed to revive on the completion of a great geological cycle. Again, to use the language of Professor Sedgwick, “each formation of geology may have required a very long period for its complete developement: but, after all, the successive formations about which we speculate, however complex in their subdivisons, are few in number; and after deciphering a series of monuments, we reach the dark ages of our history, when having no longer any characters to guide us, we may indulge at will in the creations of our fancy. We may imagine indefinite cycles, and an indefinite succession of phenomena, and in the physical

Allusion is here made to a lithographic | brethren, on a human skull, which he prosketch from the pencil of that gentleman, nounces to belong to one of the inferior entitled, “Reappearance of Ichthyosauri animals, on account of the insignificance of -man only found in a fossil state;" in the teeth, and the trifling powers of the which Professor Ichthyosaurus is repre- jaw, expressing wonder how the creature sented lecturing to an audience of his procured its food.

world as well as in the moral, we may have our long periods of fabulous history. But these things belong not to inductive geology; and all I now contend for is, that in the well-established facts brought to light by our investigations, there is no such thing as an indefinite succession of phenomena*."

When the Copernican system of astronomy was established, and the earth, no longer regarded as the centre of the universe, was proved to be one of a system of bodies revolving round the sun, the question naturally arose were the other bodies of that system habitable and inhabited; and, reasoning from analogy, astronomers were disposed to answer the question in the affirmative. It was true, that as regards the distribution of light and heat, and the intensity of gravitation, a very different state of things must prevail in most of those planets from what obtains on the earth; but seeing that every part of this earth was crowded with sentient beings, possessing an organization so adapted to the conditions of existence assigned them, as to render that existence a state of enjoyment, it appeared highly improbable that all the variety here displayed should be limited to one planet, and that all the others should be mere blanks, made only to be gazed at by us, and destitute of beings suited to their respective states. And when the modern researches of astronomy extended to the fixed stars, showed them to be suns, like that which forms the centre of our system, and when it was found that they were arranged in groups circling round each other, the argument from analogy was carried further, and the probability was inferred of each of these suns being attended by its system of planets, with their satellites, the whole teeming with life under a countless variety of forms, and under a countless variety of conditions. Geology comes in aid of these conjectures, by showing that this our planet has existed under a different distribution, of land and sea, of heat, and perhaps of light, from that which it at present enjoys; and that, under these different circumstances, it was not a mere blank, but was as much crowded as now with living beings adapted to the then state of things. A contemplation of the variety of organization manifested in the world around us, cannot fail to excite our wonder; but if we extend our researches to the remains entombed in the earth's crust, our wonder will be increased at the increased variety we shall find; and we shall be convinced that the existing system of nature is but a part of what has been, and that the whole visible creation, past and present, may be but an atom compared with the invisible.

If we apply ourselves to the task of classifying organized bodies now existing, arranging them in groups as they differ from or resemble each other in their structure, we find that those forms of each group which are most dissimilar, are connected by a series of gradations, separated from each other by the most minute distinctions, and that the groups, whether we regard the larger or the subordinate divisions, are again connected by forms possessing some of the characteristics of two groups. There are, however, cases in which the transitions are more abrupt; and when these cases occur we frequently recover, among the extinct forms of an ancient state of nature, those connecting links which are wanting

Anniversary Address—Proceedings of Geological Society, p. 305.

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in the existing creation. As instances, we may mention the ichthyosauri, before alluded to, as combining some of the characters of a lizard with those of a fish, and occupying among saurians the place of the whale and seal among mammalia; and pterodactyles which bore the same analogy to lizards, that the bat now bears to mammalia. The pachydermatous* order of mammalia, as existing at present, consists of but few genera,the elephant, rhinoceros, hippopotamus, horse, hog, and tapir, genera possessing but slight resemblance to each other, and singularly poor in species. The tertiary strata of the Paris basin abounds, however, in remains of extinct animals of this order, supplying gradations between some of the above genera, and connecting this order with others. There are, in particular, above forty fossil species of one division of it which contains only four living species. Similar instances might be adduced from other divisions of the animal kingdom; and others are afforded by a comparison of fossil and recent vegetation.

Thus existing and extinct organic bodies can scarcely be said to belong to different systems, but must be considered as composing one great chain of being, formed on one general plan, agreeing, for the most part, in important points of structure, and differing only in minutiæ of detail. And if, on examining the organization of beings whose functions we understand, we discover a mechanism like the work of our own hands, but far surpassing in beauty, and excellence, and complexity any workmanship of man: and if in this we see proofs of contrivance, of structure designed for an end, and that end accomplished, we not only discover among fossil organic bodies new and unexpected instances of this, but we have proofs that the same contriving Intelligence has been exerted at the remotest period to which we can trace back the history of the globe, ages, we know not how long, before the existence of the human race.

We find, moreover, that with every change in the state of the earth there has been a corresponding change of organized bodies, and thus we have proofs, not only of an Intelligence adapting mechanism to an end, but that the same contriving Intelligence has been manifested at successive periods adjusting the mechanism to the altered conditions under which it was to exist. With what reverential ideas ought these views to impress us respecting that Being to whom all things owe their existence, eternal in duration, absolute in power, perfect in wisdom, in goodness infinite; and how can we refrain from exclaiming in the language of Holy Writ, “ O Lord, how manifold are thy works, in wisdom hast thou made them all: they shall perish but Thou shalt endure; yea, all of them shall wax old as doth a garment, and as a vesture shalt Thou change them, and they shall be changed, but Thou art the same and thy years have no end.”

We have now pointed out some of the leading facts which geology presents to us, and some of the lofty speculations to which they lead, and we have compared them with those of astronomy. Before we proceed to the details of the science, we shall offer a few observations on the advantages attending the study, and we shall endeavour to remove those scruples which

cause many well-meaning persons to view it with an unfavourable eye, as opposed to facts recorded in the Sacred Writings.

* Thick-skinned.

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THE SALT MOUNTAINS OF ISCHIL.

My object in turning out from the direct road to Salzburg, was to visit the Gmunden Lake and the salt mountains of Ischil, which I was told I should find on its southern shore. The road, after leaving Lambach, led by the Traun river, by which the 'lake discharges itself into the Danube, and down which the salt is conveyed in large flat-bottomed boats. It is an extremely turbulent and rapid stream, and at one spot, where is a high picturesque fall, a wood-shot has been constructed, down which the boats glide with frightful rapidity. At the head of the lake is the village of Gmunden, where is a depôt for salt, and a large manufactory of casks, both belonging to the government. I found here two German students, also pedestrians, with whom I kept company on to Salzburg. We hired a boat to convey us to the other end of the lake. It was rowed by two: men and a girl, there being scarcely any kind of manual labour from which the females of the lower class in Germany are exempted. The lake is romantically situated, having on the eastern side a range of mountains rising boldly from the water, and on the other a champaign country highly cultivated, and sprinkled with herrschaufts* and farmhouses. Among the former was the Traun Stein, which rises abruptly from the lake about two miles from its outlet. It was a bright morning; every object looked cheerful, and my companions when out on the lake commenced a song about freiheit and vaterland, to an air that I had often heard among the Germans of my own father-land Pennsylvania. Suddenly the boat stopped, and the father of the crew, rising up, sprinkled us with water, and with the usual ceremony of baptism gave us each the name of one of the surrounding mountains.

We landed at Ebens-see, a small village at the southern end of the lake, and in reply to our inquiries, they informed us that the salt was manufactured at this place, but that the salt-mines were several miles in the interior. I had supposed that the salt was dug in a solid state from the mountain, and was therefore surprised when they took us to a large building, in which was a sheet-iron pan about sixty feet in diameter and two in depth, with a brisk fire kept up beneath. Water was flowing into it from two huge cocks, and workmen were employed shoveling salt out from the bottom on to a draining-board, from which it was afterwards removed to small cone-shaped vessels, with holes at the bottom for further draining. In these it was suffered to remain until it became solid, when it was turned out, and the moist end of the cone being cut off, it was ready for transportation. Each lump contained about thirtythree pounds.

From Ebens-see we followed the windings of a deep valley for nine miles, when we arrived at Ischil, a pretty little village, frequented by valetudinarians for the benefit of its salt-baths. These are in a new and very handsome edifice, with a Grecian colonnade in front, and an inscription, In sale et sole omnia existunt. The salt mountains are about three miles to the southward of Ischil. They form part of a high and broken range extending eastward and westward, and in the exterior are not to be

* The residences of the titled proprietors.

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