merous fossil remains, while Humboldt found a rock, similarly characterized, among the Andes, at the height of 14000 feet. The ancient philosophers, who, in other departments of physical science, were far behind the moderns, seem in this alone to have pursued a process of inductive reasoning, which led to results far more accurate than any attained by the moderns, until within a very few years. The dogmatism which determined to find in every fossil aquatic remain a proof of the particular Noachic deluge, and the timidity of those whose researches had made them better informed, left the world wholly in the dark as to the real inferences to be drawn from a study of the structure of the earth; but what modern geologist could better express what are now admitted opinions, than the words which the Roman poet puts in the mouth of Pythagoras. "Vidi ego, quod quondam fuerat solidissima tellus, Quæque sitim tulerant, stagnata paludibus hument. Clausit et antiquis concussa tremoribus orbis : Flumina prosiliunt; aut excæcata resident.” The order in which fossil remains are found to succeed each other in the successive formations that are to be traced from the oldest rocks to the diluvial deposit, are well illustrated in the words of a late distinguished philosopher, whom we shall quote. "In those strata which are deepest, and which must consequently be supposed to be the earliest deposited, forms, even of vegetable life, are rare; shells and vegetable remains are found the next in order; the bones of fishes and oviparous reptiles exist in the following class; the remains of birds, with those of the same genera mentioned before, in the next order; those of quadrupeds of extinct species in a still more recent class; and it is only in the loose and slightly consolidated strata of gravel and sand, and which are usually called diluvial formations, that the remains of animals such as now people the globe are found, with others of extinct species. But in none of these formations, whether called secondary, tertiary, or diluvial, have the remains of man, or any of his works, been discovered: and whoever dwells upon this subject, must be convinced that the present order of things, and the comparatively recent existence of man as the master of the globe, are as certain as the destruction of a former and different order, and the extinction of a number of living forms, which have types in being. In the oldest secondary strata there are no remains of such animals as now belong to the surface; and in the rocks which may be regarded as most recently deposited, these remains occur but rarely, and with abundance of distinct species;-there seems, as it were, a gradual approach to the present system of things, and a succession of destructions and creations preparatory to the existence of man." We have stated that the zoophytes and shell-fish have left the most numerous fossil remains. Those of other families are not however rare. Fish, for instance, are found in great abundance, near Glarus in Switzerland, in clay slate; in Germany, at Papenheim, in a slaty marle, in the cupriferous slate of Eisleben, in the fetid limestone of Oehningen. They are also found in Egypt, and we have specimens of the same sort from Lyria, in a limestone apparently belonging to the oolitic or Jura formation. China and the coast of Coromandel have also fossils of this sort, but by far the greatest quantity have been procured from Mount Bolca, near Verona. A splendid suite from the last locality are to be seen in the Gibbs' Cabinet at New-Haven. Besides the impressions of entire fish, separate portions are very abundant, and perhaps the most frequent of these are the teeth of sharks, which are sometimes of a magnitude vastly greater than those of any living species. Animals of the class of amphibia appear not to have existed until after the æra that gave birth to fish. The oldest are probably the tortoises, of which a specimen has been found in sandstone near Berlingen. They have also been found in England, in the Netherlands near Brussels, at Aix in Provence, and in the quarries near Paris. The most remarkable fossils of this class belong, however, to the lizard family. Of these the most remarkable are the plesiosaurus, the megalosaurus, the iguanodon, and the crocodile of Maestricht, all belonging to extinct species. The marine animals that are met with in a fossil state, are in great part foreign to the climates in which they are found buried. It has been shown that the fish of Bolca have their nearest living prototypes in the seas of Otaheite. The perpites of Gothland have been supposed to be petrifactions of the medusæ of India. The madrepores, so abundant in Russia and in the frozen deserts of Siberia, only live now in seas within the tropics. Shells analogous to a great part of those found fossil in England, are only to be seen in the Atlantic, in a living state, on the coasts of Florida and Cuba. A shell-formed fossil at Havre is only to be met with recent at Amboyna. Of the shells found in Italy, fossil in the sub Appenine hills, many are common to the Mediterranean and the Indian oceans. But while those in the fossil state and the recent specimens from the tropics correspond in size, individuals of the same species from the Mediterranean are dwarfish and degenerate. Thus then the remains of aquatic and amphibious animals appear to confirm the conclusion drawn from vegetable fossils, that a climate of temperature as elevated as that now found in the tropics, once extended into high northern latitudes. It has been seen that the fossil remains and impressions of shells have been found at great heights upon the sides, and even upon the tops of mountains; and that in the older of the strata no trace is to be found of any but aquatic animals. Thus before our existing mountains and the minerals they contain had arisen above the general surface; before diluvial and alluvial deposits, or even the great formations of sandstone and conglomerate had arisen from their disintegration, the globe was covered, in a great degree, and as it appears from considerations we have not space to enter into, by various successive eruptions, with waters, sometimes fresh, sometimes saline. These waters have, it could be readily made to appear, often rested long on the surface in a quiet state, after having been in violent agitation; and long ages of tranquillity have been succeeded and closed by, convulsions of the most violent character. In all the regularly stratified formations, animals of the mammiferous or cetaceous classes are wholly wanting; at least we have no proof that can be relied upon of any having been found in formations which took place prior to the last great deluge, that covered so much of the land with diluvium. In this last formation, however, they are often found in great abundance. Some of them are of recent, others of extinct species. Among the most remarkable of the latter are, the palæotherium, and anoplotherium, found near Paris; the megalonyx, an animal of the sloth genus, but of the size of an ox, found in Virginia; a still larger sloth, called the megatherium, found near Buenos Ayres ; the fossil elephant, as different from the living elephants of India or Africa, as the horse is from the ass, and which has been found in Europe, in Asia, and in America. The mastodon, of which several species have been discovered on the banks of the Hudson, in Kentucky, in Louisiana, in the plains of Quito, in France, and finally on the borders of the Irrawaddy. The bones of rhinoceroses, bears, elephants, and hyænas, have been found mixed in confusion in caverns; and it has been shown by Buckland that the latter animal had inhabited these caverns, and drawn thither the carcasses of the others as his prey, in one of the most perfect inductive arguments which has been produced, since Bacon propounded the rules of that species of reasoning. "The moveable earths that fill the bottoms of valleys, and which cover the surface of great plains, have furnished us in the above two orders, of pachidermata and elephants, the bones of twelve species, to wit: one rhinoceros, two hippopotami, two tapirs, an elephant, and six mastodons. All these twelve species are now absolutely extinct in the climates in which their bones are found. The mastodons alone may be considered as forming a separate genus, now unknown, but closely approaching to the elephant. All the others belong to genera now existing in the torrid zone. Three of these living genera are now found only in the ancient continent, to wit: the rhinoceros, the hippopotami, and the elephant; the fourth, that of the tapirs, only exist in the new. The distribution of the fossil species is different; the tapirs have been found only upon the old continent, while elephants have been discovered in the new." The fossil species, although belonging to known and existing genera, are essentially different in species from those which now live upon the earth. The former are not mere varieties, but have marked specific differences. This at least is beyond all doubt in respect to the smaller of the hippopotami, and the gigantic tapir, as well as the fossil rhinoceros, and is extremely probable in respect to the elephant and the smaller tapir. If there be any question of the fact, it is only in respect to the greater hippopotamus. "These different bones are buried in all different places in beds that resemble each other. They are often mixed indiscriminately with those of other animals, identical with those which exist at present. These beds are generally moveable, sandy, or marly, and always within a short distance of the surface. It is therefore probable that these bones have been enveloped by the last catastrophe of the globe. In a great number of places, they are accompanied by the accumulated spoils of marine animals; in other places, but these are less numerous, the remains of marine animals are not found, and sometimes the sand or marle that covers them contains only fresh-water shells. Although a small number of shells attached to fossil bones indicate that they have remained some time under water, yet is there no authentic account of their having been found covered with regular stony beds, filled with marine remains, nor, in consequence, is there any proof of the sea having made a long and peaceable stay above them. "The catastrophe that has covered them, would appear then to have been a great marine inundation, of no long duration, were it not that they are found upon the tops of high mountains, whither the waters of our present ocean could never have reached in their most violent agitations. On the other hand, these bones presenting no appearance of having been rolled, being occasionally only fractured, as the remains of our present domestic animals may occasionally be, and being sometimes found in entire skeletons, and accumulated as if in a common cemetery, demonstrate that the living beings to which they have belonged, must have met their fate in the very parts of the globe in which we now find the fossil monuments of their existence." All the animals of which we have particularly spoken, are of genera now only found in the torrid zone, and the abundance of food which their great size would have caused them to require, renders their existence in numbers only possible in a warm climate. Their remains are, however, found in almost polar regions, whence we obtain a third link in the chain of evidence, that before the last great catastrophe to which the globe was subjected, its surface must have been warmer than at present. We have seen in a former place, that such a change of temperature may have gradually occurred in consequence of a cooling of the external surface of the globe by an excess of its radiation above the quantity of heat received from the sun. The final cooling of its solid crust, down to the mean temperature at which we now find it, might, as is obvious, have been effected by a great irruption of waters, like that of which we have distinct evidence in the diluvial deposits, and the animal remains upon its surface. From that time, a state of equilibrium in the action of solar and terrestrial radiation having been attained, while the mean temperature still continues to depend upon the internal structure and nature of the globe, the distribution of heat upon the surface, and the vicissitudes of the seasons, have been solely influenced by the varying relation between these two radiations, which if equal to each other in their total amounts, differ in every different latitude, for every successive day in the year, and during each varying hour of the day. It has been attempted to explain this change that has unquestionably taken place in the temperature of climate, by conceiving a change in the situation of the earth's axis. This hypothesis, however, is shown to be untenable by the calculations of physical astronomy: no other cause then remains but an actual change in the condition of the earth itself. The most remarkable of all the phenomena which the earth presents, are the great changes of weight that have taken place in identical formations which must have arisen from the prevalence of water, and therefore nearly if not exactly upon the same level. The primitive or lowest stratified rocks, probably had not water for their cause; still, however, they must have been in the fluid state, and these are not only found beneath all other rocks, and in the lowest places to which the industry of man has penetrated, but they also rise and form the greatest part in bulk of many of the highest mountains; indeed, if we except volcanic mountains, of all the more elevated masses. The transition and secondary formations are subject to similar although less changes of level, rising, as has been seen, to the tops of the Pyrenees, and to even a greater height on the sides of the Andes. The tertiary or superior formations are found in Italy and Sicily, forming mountains several thousand feet in height, while the latest of all, the diluvial with its embedded mammalia, exists in the lofty table land of Quito. The inference is irresistible, that we do not now find these deposits at the levels where they were left by the ocean, as in the case of the primitive rocks by their own crystallization from a fluid state, but that they have been altered in their positions by actions of a character totally distinct from that by which they were originally formed. This inference is still further confirmed by the great and sudden changes of level that are frequently to be seen in similar strata, faults, as they are styled by miners, in which the same bed has its level sometimes changed hundreds, nay even thousands of feet. These faults, if in greatest abundance in the more ancient rocks, are to be found even in the newest, and sometimes affect several formations incumbent on each other, of ages the most different. Thus, then, we have distinct and conclusive evidence, that as we inferred from theory, the solid crust of the globe has been shattered and fractured repeatedly, and at all the different epochs of its history. This fracturing and cracking we have shown, must, in conformity with strict mechanical laws, have been attended with the rise of the molten liquid from beneath, which ought in some cases to have formed veins and dykes, in the places where the fractures occurred. It is however possible, that the rise of the fluid from beneath, may not have taken |