Page images
PDF
EPUB

the largest of these equalled a rhinoceros in magnitude, others were of the sizes of the pig and the sheep, and the smallest was no larger than the hare. Of the Lophiodon, a genus that also bore a considerable resemblance to the Tapir, more than twelve species have been determined; the largest of these was about the size of the rhinoceros, and the smallest about that of a lamb three months old. Of the extinct genus Anoplotherium, which differs extremely in anatomical character from any now known, six species are already ascertained:-the largest came near in size to the ass; another to the gazelle, which it is supposed to have rivalled in the elegance of its form; another did not exceed the hare in size, and some were still smaller. The species most frequently met with in the gypsum of Paris was about the height of a wild boar, but had nearly the proportions of the otter; it had a thick and long tail, and probably swam well and frequented the lakes, in the bottom of which its bones have been incrusted with the gypsum there deposited.'§ Of the extent of these ancient lakes the geologist can still form some idea, when he has traced in his map the boundaries of strata replete with the remains of freshwater animals and plants. Of the genus Antracotherium, two species have been found, one of the size of a Rhinoceros, the other smaller: these were intermediate between the Palæotherium, Anoplotherium, and Hog. Of each of the genera Cheropotamus and Adapis, one species only is known, about the size of a rabbit. In the same formation with these herbivorous animals a few carnivorous ones are found; a Fox, a Gennet, a Bat, and a small Opossum, (a genus unknown till the discovery of America,) and some few others. Skeletons also of a dormouse and a squirrel occur, besides the bones of birds, crocodiles, freshwater tortoises, and fish; nor are shells wanting. The whole of these are either of extinct genera or of unknown species.

cies.

The plants on which these large herbivorous animals were supported differed as widely as themselves from all known spePalms, reeds, and many other kinds are met with in these strata, indicating upon the whole the vegetation not of tropical climates as does the flora of our secondary formations and parficularly of the coal-but rather such as now clothes the countries bordering on the Mediterranean.

No remains of the human species have been found with the above fossil animals, nor elsewhere in any stratum having pretensions to immemorial antiquity. It is nearly a century since Bishop Berkley remarked, that if Man had existed for so many

* Cuv. Discours sur les Rev. p. 315, 316. 1825.
† Ib. p. 319.
+ Ib. p. 320.

Ib. p. 321.

ages

[ocr errors]

ages as some nations and some philosophers have maintained, gems, medals, and implements, in metal or stone, would have lasted entire, as the shells and stones of the primeval world are preserved down to our time;'* he might have added that human skeletons would have also attested the fact, for Cuvier has shown that there are strong grounds for believing these to be as little perishable in their nature as those of other animals.+ But the entire absence of all Quadrumana-such as the durang-outang, ape, monkey, baboon, and many other genera-is a circumstance not less striking. The animals of this family are at present as numerous as other grand divisions of Mammalia, and in their osteological characters they approach much nearer to the human species than any others. They are almost exclusively confined at present to countries lying between the tropics, and never far exceed this limit;-but as the same may be said of the Elephant, Rhinoceros, Hippopotamus, Tapir, and other genera, as well as of the reptiles so abundant in a fossil state in Europe, some extinct species at least of the Quadrumana might have been looked for. An opinion was entertained soon after the commencement of the study of organic remains, that in ascending from the lowest to the more recent strata, a gradual and progressive scale could be traced from the simplest forms of organization to those more complicated, ending at length in the class of animals most related to man. And such is still the general inference to be deduced from observed facts, though some recent exceptions to this rule are too well authenticated to justify an implicit reliance on such generalizations.

But what is most important with regard to the history of the above-mentioned lost race of quadrupeds, is the circumstance that both in the environs of Paris and in those of Orleans, as well as in Berri, and in a district not far from the Rhine, near Strasburgh, the strata inclosing them are again covered with marine deposits. A careful examination of the contents of these leaves no doubt that the sea returned and covered the land on which the animals had lived, and where the rivers and lakes were situated, in the beds of which their remains had been buried. To such an event M. Cuvier has attributed with great probability the annihilation of the quadrupeds then inhabiting the ancient continents. But to what known agents in nature can we ascribe such destructive catastrophes ? The great winding sheets,' says Lord Bacon, that bury all things in oblivion are two, deluges and earthquakes. That these two causes have in fact conspired in former

Berkley, Min. Phil. vol. ii. p. 84.

Cuvier, Discours sur les Rev., &c. p. 157. 1825.
Essay on the Vicissitude of Things.

VOL. XXXIV. NO. LXVIII.

K K

periods

periods and at different intervals of time to destroy the animate productions of nature, modern industry has afforded ample proof; but the labours of geologists have also shown how much of the history of extinct races may yet be rescued from oblivion. It is now twenty years since Playfair observed, that the land has been raised by expansive forces acting from below, and there is reason to think, that continents have alternately ascended, and descended, within a period comparatively of no great extent.' When the Huttonians first advanced these doctrines, no geologists disputed that there existed proofs of former changes, in the relative level of land and sea, but Playfair's hypothesis appeared extravagant to many, and those were deemed 'fearless of paradox who,' as Mr. Greenough expressed it,* attributed to the waves constancy, mobility to the land.' Yet the Huttonians were conducted to these conclusions by the observation of a class of phenomena altogether distinct from what may now be considered as furnishing the most decisive evidence in favour of them. Playfair had examined with attention the dislocations and disturbances of rocks, but the alternation of a great series of marine and freshwater formations was not then established,-nay, has only been generally admitted since all the facts from which it is inferred have been rigorously examined by persons possessing a competent knowledge of organic remains, and who have compared recent with ancient freshwater deposits.

It

may not be superfluous to mention a few of the most striking of these facts. The strata associated with the Coal contain in many countries indications of a fresh-water origin; and the vegetable remains preserved in them prove the existence of dry land at the period of their deposition. The bituminous copper slate of Thuringia is of an older date than the magnesian limestone of the English series; it contains reptiles of the Saurian family, closely resembling the great monster that now lives in fresh water in the torrid zone,† and the unknown fish that abound in the same slate are regarded by Cuvier as related to freshwater genera. Strata of freshwater origin, and of considerable thickness, exist between the chalk and the oolitic series in the south-eastern districts of England. The chalk is exclusively a marine deposit; and, from its great extent in Europe, and the absence of vegetable matter, sand and transported materials, is considered to have been formed at the bottom of a deep and tranquil sea. But above the chalk, both in this island and on the continent, alternations of marine and freshwater strata occur. The lowest of these are

* A Crit. Exam. of the First Principles of Geology, 191.

+ Cuv. sur les Rev. p. 299.

See Mem. by Dr. Fitton, Ann. of Phil. Nov. 1814.

filled with vegetable matter, and in some localities in France with freshwater shells. Upon this group of strata a formation rich in a great variety of marine remains is placed, both here and in France: above that formation, again, is the freshwater deposit already referred to as including terrestrial quadrupeds; this is again covered in its turn by marine beds; and incumbent upon them in like manner another series of freshwater strata is found.

To explain such phenomena by supposing that the ocean has alternately risen and fallen, in other words, that its level has been, both frequently and permanently, changed over the whole globe, is an hypothesis unsupported by facts. But of changes in the level of the land we have ample testimony, and some are particu larly recorded in the volume before us,* where an account is given of the late memorable earthquake that visited Chili in 1822, and continued to be felt there till near the end of 1823. The shocks of this earthquake were experienced throughout a space of 1200 miles from N. to S., and at Valparaiso it appeared, on the morning of the 20th, (Nov. 1822,) that the whole line of coast from N. to S., to the distance of above 100 miles, had been raised above its former level;' an old wreck of a ship, which before could not be approached, was now accessible from the land. The alteration of level† at Valparaiso was about three feet, and some rocks were thus newly exposed, on which the fishermen collected the scallop, which was not known to exist there before the earthquake. At Quintero the elevation was about four feet.

[ocr errors]

'When I went to examine the coast,' says Mrs. Graham, although it was high-water, I found the ancient bed of the sea laid bare and dry, with beds of oysters, muscles, and other shells adhering to the rocks on which they grew, the fish being all dead, and exhaling most offensive effluvia. I found good reason to believe that the coast had been raised by earthquakes at former periods in a similar manner, several ancient lines of beach, consisting of shingle mixed with shells, extending in a parallel direction to the shore to the height of fifty feet above the sea. The country has in former years been visited by earthquakes, the last of any consequence having been 93 years ago.'‡

Part of the coast thus elevated is stated to consist of granite, in which great parallel fissures were caused by the earthquake. Besides the excellent account of these phenomena given by Mrs. Graham, the observations of several other persons were published in the Journal of the Royal Institution, where it is stated, that 'the whole country, from the foot of the Andes to far out at sea, was raised, the greatest rise being at the distance of about two

[blocks in formation]

miles from the shore;' the supposed area over which the earthquake extended on the land was estimated at 100,000 square miles. The rise upon the coast was from two to four feet:— at the distance of a mile inland it must have been from five to six, or seven feet.'*

Nearly at the same period, when these stupendous events were occurring in South America, Dr. Jack was, by a singular coincidence, composing his paper (which also appears in the present volume) on the geology of Pulo Nias, near Sumatra, to which island the author accompanied the late amiable and lamented Sir Stamford Raffles.

Near the surface on all the hills,' he observes, f masses of coral origin are found lying immediately above the rocky strata, and, to all appearances, precisely in their original position, in general so little altered, that their different species can be determined with certainty.' These species are described as obviously the same with those which now abound in the neighbouring sea, such as the madrepora muricata, and other branched kinds,

and sometimes,' he continues, the transition from the recent to the fossil coral, is only effected by the gradual rise of the land from the shore. Large kima shells (chama gigas) are also found on the hills, exactly as they occur in the present reefs, and are collected by the inhabitants for the purpose of cutting into rings for the arms and wrists. Every thing seems to indicate that the surface of the island must at one time have been the bed of the ocean.'‡

From the great inclination of the strata of Pulo Nias, and the dislocation they sometimes appear to have suffered, and from the absence of similar unchanged and unfossilized corals and shells on the adjacent coast of Sumatra, Dr. Jack inclines to the hypothesis that there has been a heaving up of the island by a force from beneath;-Nay,

[ocr errors]
[ocr errors]

although it must be regarded,' he adds, as a phenomenon of a most singular kind, that so large an island, diversified with numerous hills from 800 to 3,000 feet in height, should have been heaved up from the sea with so little disturbance to the fragile marine productions on the surface,—the appearance and nature of these productions would indicate a comparatively recent date to the event.'§

In a paper by Mr. Strangways on the geology of Russia, (also included in the volume now under review,) are some very important observations on the great changes in the distribution of land and sea that seem to have occurred at no distant period in one of those few portions of the globe of which we have any an

Jour. Roy. Inst. for 1824. vol. xvii. pp. 40. 45. + Page 403. + Page 404.

§ Ibid.

« PreviousContinue »