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been exterminated at the "wreck" of the world, which they regard as having immediately preceded the six days' creation. According to the axioms, however, by which they profess to be governed, they cannot assume such a stupendous occurrence and make it the basis of their theory, unless it can both be proved from the strata in which those relics are imbedded, and shown that it was produced by the chemical and mechanical forces to which they refer the geological facts on which they reason. But neither of these propositions can they prove. They do not undertake it. It were preposterous to attempt a demonstration from their nature, position, numbers, or any other consideration, that none of them descended from those that were created on the third, fifth, and sixth days of the Mosaic epoch. It were equally absurd to attempt to produce evidence that they were destroyed by chemical agents, volcanic .fire, or the mechanical force of water. If it could be shown that those agents were adequate to their destruction, if brought in great force in contact with them, it is not possible to prove the fact of their contact. Here is thus another indispensable condition to the verification of their theory, that is taken for granted by them without evidence, and in contravention of their own principles, which prohibit their assuming the occurrence of any geological events that are not demonstrable from the earth's strata, and that are not the result of chemical and mechanical forces.

In the third place, there not only is no geological evidence that the animals that are fossilized were not either derived from those that were called into life in the six days of the Mosaic creation, or at a later epoch, but belonged to races of an anterior date; but there is positive and unanswerable proof to the contrary, in the fact that great numbers of those imbedded in the tertiary strata are of identically the species that now inhabit the seas and the earth. Thus Sir Charles Lyell says:

"M. Deshayes, of Paris, well known by his conchological works, at my request, drew up in a tabular form a list of all the shells known to him to occur both in some tertiary formation and in a living state, for the express purpose of ascertaining the proportional number of fossil species identical with the recent, which characterized successive groups; and this table, planned by us in common, was published by me in 1833. The number of tertiary fossil shells examined by M. Deshayes was about 3,000; and the recent species with which they had been compared, about 5,000. The result then arrived at was, that in the lower tertiary strata, or those of London and Paris, there were about 3£ per cent, of species identical with recent; and in the middle tertiary of the Loire and Gironde, about 11 per cent. ; and in the upper tertiary or sub-alpine beds, from 35 to 50 per cent. In formations still more modern, some of which I had particularly studied in Sicily, where they attain a vast thickness and elevation above the sea, the number of species identical with those now living was believed to be from 90 to 95 per cent. ...

"Since the year 1830, the progress of conchological science has been most rapid, and the number of living species obtained from different parts of the globe has been raised from about 5,000 to more than 10,000. New fossil species have also been added to our collections in great abundance; and at the same time a more copious supply of individuals, both of fossil and recent species, some of which were previously very rare, have been procured, affording more ample data for determining their specific character. . . .

"I have adopted the term post-pliocene for those strata which are sometimes called post-tertiary, or modern, and which are characterized by having all the imbedded fossil shells identical with species now living, whereas even the newer-pliocene, or newest of the tertiary deposits above alluded to, contain always some small proportion of shells of extinct species.

"These modern formations thus defined, comprehend not only those strata which can be shown to have originated since the earth was inhabited by man, but also deposits of far greater extent and thickness, in which no signs of man or his works can be detected. In some of those of a date long anterior to the times of history and tradition, the bones of extinct quadrupeds have been met with of species which probably never co-existed with the human race, as for example, the mammoth, mastodon, megatherium, and others, and yet the shells are the same as those now living.

"In Ischia, near Naples, ... Dr. Phillipi collected in the stratified tuff and clay ninety-two species of shells of existing species. ... In the centre of Ischia, on the lofty hill called Epomeo, at the height of about 2,000 feet, ... I collected in 1828 many shells of species now inhabiting the neighboring gulf. It is clear, therefore, that the great mass of Epomeo was not only raised to its present height, but was also formed beneath the waters within the post-pliocene period.

"Such an upward movement has been proved to be in progress in Norway and Sweden throughout an area about 1,000 miles north and south, and for an unknown distance east and west. . . . Accordingly, we find near Stockholm, in Sweden, horizontal beds of sand loam and marl containing the same peculiar assemblage of testacea which now live in the brackish waters of the Baltic.

"On the opposite coast of Sweden, post-pliocene strata containing recent shells, . . . such as now live in the northern ocean, ascend to the height of 200 feet; and beds of clay and sand of the same age attain an elevation of 300 and even 700 feet in Norway.

"Judging by the uniformity of climate now prevailing from century to century, and the insensible rate of variation in the organic world in our own times, we may presume that an extremely lengthened period was required even for so slight a modification of the molluscous fauna, as that of which the evidence is here brought to light. On the other hand, we have every reason for inferring, on independent grounds, namely, the rate of upheaval of land in modern times, that the antiquity of the deposits in question must be very great. For, if we assume that the mean rate of continuous vertical elevation has amounted to 2£ feet in a century, and this is probably a high average, it would require 27,500 years for the sea-coast to attain the height of 700 feet, without making allowance for any pauses, such as are now experienced in a large part of Norway, or for any oscillations of level." —Manual of Geology, pp. 110-115.

Species that are now living occur in great numbers in the newer pliocene strata, the upper of the tertiary.

"M. Murchison and De Yerneuil found in 1840 that the flat country between St. Petersburgh and Archangel, for a distance of 600 miles, consists of horizontal strata, full of shells similar to those now inhabiting the Arctic Sea, on which rested the boulder formation.

"In Sweden in the neighborhood of Upsala, I observed in 1834 a ridge of stratified sand and gravel, in the midst of which is a layer of marl, evidently formed originally at the bottom of the Baltic, by the slow growth of mussel, cockle, and other marine shells, intermixed with some of the fresh-water species. The marine shells are all of dwarfish size, like those now inhabiting the brackish waters of the Baltic; and the marl in which myriads of them are imbedded is now more than 100 feet above the level of the Gulf of Bothnia. Upon the top of this ridge repose several huge erratics, consisting of gneiss, . . . which must have been brought into their present position since the time when

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