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tals; the remaining foot and a half to the bottom, contained an aggregate of water-worn stones which were from the size of a goose's egg to that of a small walnut, and consisted of red jaspers, yellowish-white flints, white quartz, and bluish-white agates, firmly combined by a yellowish brown stalactitical calcareous spar. In this breccia I could not discover any fragment of the mountain rock, or any other calcareous matter, except the cement with which it was combined. This pot is 940 feet above the level of the sea."

The red argillaceous earth forms the diluvial matrix of the bones in the caves and fissures immediately below; and the pebbles lodged with it on the summit of an insulated and precipitous mountain of limestone, are analogous to the blocks of Mont Blanc granite lodged on the high slopes of the Jura mountains; both having been forced up into their present places by the deflux of the deluge.

All these circumstances concur to establish an identity of time and manner in the formation of the osseous breccia that fills the fissures and caves of Gibraltar, &c., with that of the conglomerate loam, which occurs in the caves and fissures of Germany and England. Had the mud and pebbles been introduced into the caves before they were inhabited, they would have formed the lower stratum of the floor, over which the animal exuvia would have been strewed; a condition totally different from the reality. The bones are indiscriminately distributed throughout the diluvium of mingled loam, sand, and pebbles, forming a paste, which the deeper we descend into the caverns, becomes thicker and thicker, till in the lower regions and under-vaultings, it chokes up the whole rocky excavation, thus affording the most graphic traces of the deluge, pouring down its debacle. That the bones were not washed into these vaults, from the open surface of the earth, is proved by the fact, that while every cave contains nearly the same proportion of

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pebbly detritus, the occurrence of bones is limited to a small number; and in these they are crowded in such enormous quantities, and are so distributed as to demonstrate their pre-occupancy of the chambers. Nor has there been a succession of these mighty cataclysms; for there is only one crust of stalagmite, covering one agglomeration of gravel and bones; whereas on the former supposition, alternate strata would have been found.

The appearances in the Oreston caves near Ply. mouth, assimilate them more with the fissures of Gibraltar and Duncombe Park, than with the Kirkdale and other antediluvian dens. There was in the former, a nearly perpendicular hole, containing bones quite untouched by violence of any kind, lodged in irregular heaps in the lowest pits, and in recesses along the lateral enlargements of the hole, mixed with mud, pebbles, and fragments of limestone, in a manner precisely similar to the osseous breccias of the Mediterranean shores. Professor Buckland therefore concludes that the animals had fallen during the antediluvian period into the open fissures, and there perishing, had remained undisturbed in the spot on which they died, till drifted forwards by the diluvian waters to their present place in the lowest vaultings with which these fissures had communication. The wolves and hyænas may have either fallen by accident like the horses, oxen, and deer, into natural pitfalls in the Oreston rocks, or have recklessly leaped into them to devour the dead carcasses of the graminivorous animals. The large proportion of the latter animals to the carnivorous is quite consistent with this

hypothesis. In the districts of mountain limestone in Monmouth and Glamorganshire, the cattle have to be protected from such accidents, by the erection of walls round the open crevices.

The lamantine and dugong are two large cetaceous animals somewhat similar to seals, which now frequent, the former, the coasts of South America and Africa, the latter the Indian seas. They are both graminivorous, living on sea-weed, are accordingly furnished with grinders in their jaws, and never recede far from the shore, but sometimes advance into the mouths of rivers. Some bones of the lamantine have been extracted from a coarse shell limestone on the banks of the little river Layon, in the department of the Maine-et-Loire, as also in several other parts of France. M. Cuvier infers that it is very certain that an animal of the lamantine genus-a genus now peculiar to the torrid zone, dwelt in the ancient sea, which has covered the lands of Europe with its shells at a period posterior to the chalk formation, but anterior to that in which the gypsums were deposited, when the palæotheriums, and their contemporary genera lived in these latitudes.

Fossil Dolphins.-In 1800, M. Cortesi of Piacenza, collected some bones of the elephant and rhinoceros on the summit of Mount Pulgnasco, one of the hills which descend from the lofty Appenines towards the plain of the Po. They lie almost on the surface. Parallel to Mount Pulgnasco, to the east, and separated from it by the small stream called Stramonte, there is another hill much lower named Torazzo, from the remains of an old tower, and

FORMER AND PRESENT EARTH COMPARED. 593

composed, like the base of Pulgnasco, of a bluish clay, filled with sea shells. In this hill, about 120 feet above the Stramonte, M. Cortesi, attracted by a vertebra which had been brought to him from this place, made excavations, and discovered the nearly entire skeleton of a dolphin; a success which excited him to very zealous researches since that time. The fish to which that skeleton belonged must have been about thirteen feet long. M. Cuvier considers it to be of a different species from the dolphins now known to naturalists. Fossil remains of another dolphin. have been found at Sort, a village in the department of Landes, two leagues from Dax, buried in a bed of broken shells and other marine productions. The whole length of the animal when alive must have been 9 feet; and it seems also to differ from existing species. Some other fossil fragments of dolphins have been found in other places.

CHAP. VII.-THE PRESENT EARTH, AND ERA OF ITS

EMERGENCE.

THE original dry lands having been upheaved from the circumfluent abyss, prior to the creation of the animal tribes, were truly primitive formations, affording naturally to the husbandman a dense and stubborn soil. But the mineral strata formed under the ocean during the antediluvian interval, were planes of argillaceous and siliceous loam, through which, calcareous matter, in a friable state, was largely and universally distributed by organic secretion. That term of the terraqueous constitution may therefore be compared to the larva state of some animals,

during which the grand metamorphosis was slowly preparing for the production of a better and more enduring earth, when that ancient ocean should transfer its mass to a new bed, possibly that of our present Pacific, Mediterranean, &c. while the secondary strata, as of Italy, France, England, and other countries, were elevated and laid dry. The physical proofs of such changes have been fully detailed in the former chapters of this work.

Calcareous matter is indispensable both as a stimulus and a food to plants, but the compact semi-crystalline texture of primitive limestone, and its insulation in detached mountain blocks, are unpropitious to its agricultural influence. When disseminated in the form of pulverised shells and marl, it becomes so beneficial to vegetation, that mixed in due proportions with alumina and silica, it may constitute a soil inexhaustibly fertile.* Hence primitive and transition districts of country, like Cornwall and Northumberland, are as readily recognised by the farmer as by the geologist.

The antediluvian dens, so skilfully deciphered by Dr. Buckland, serve unquestionably to show, that certain strata of submarine formation, richly replenished with shell limestone, had been elevated into habitable land long prior to the deluge, a corol lary from our principles of the unstable equilibrium of the primeval globe. And the whole phenomena of geology concur to prove, that much of the richest

* A very productive soil, from the banks of the river Parret, in Somer setshire, afforded to Sir H. Davy four-fifths of its weight of carbonate of lime; and another yielding excellent pasture, from the valley of the Avon, near Salisbury, gave three-fifths.—Agricultural Chem. pp. 201, 202.

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