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Show 46 UZZORO MORO.-OENEREJ,LJ, h ld h .l' unded the world upon such laws, as that nature s ou ave 10 d 1 d l d h ld for ever be growing smaller, an at ast the ry ahn lis oubmerged beneath the waters? Is it credible become w o y su . l h ld that, am1' d so man y created things ' the m. ountamhs a obn e. s ou . 1 d' · · 1 in number and bulk, without t ere emg any dat ~ Ifmtthm~ l losses ? 'I.' his would be contrary to that order repair o elr ll h h. . h of Providence wliich is seen to reign in a ot er t mgs m t c um·v erse. Where.~:11o re I deem it J. u~t to conclude, that the • • d . hl'c}1 1'n the beginning of time, ra1se mountams ~~m~w , . from the abyss, has, down to the present day,, contmued to produce others, in order to restore from time to time the losses f 11 such as sink down in different places, or are rent asunder, ~r ~n other ways suffer disintegration. If this be admitted, we can easily understand why there should now be found upon many mountains so great a number of crustacea and other marine animals.'' 'l'he reader will remark, that although this admirable essay embraces so large a portion of the principal objects of geological research, it makes no allusion to the extinction of certai.n classes of animals ; and it is evident that no opinions on th1s head had, at that time, gained a firm footing in Italy. That Lister and other English naturalists &hould long before have declared in favour of the loss of species, while Scilla and most of his countrymen hesitated, was natural, since the Italian museums were filled with fossil shells, belonging to species of which a great portion did actually exist in the 1\tiediterranean, whereas the English collectors could obtain no recent species from their own strata. The weakest point in Moro's system consisted in deriving all the stratified rocks from volcanic ejections, an absurdity which his opponents took care to expose, especially Vito Amici*. Moro seems to have been misled by his anxious desire to represent the formation of secondary rocks as having occupied an extremely short period, while at the same time he wished to employ known agents in nature. 1.'o imagine torrents, rivers, currents, partial floods, and all the operations of moving water, to have gone on exerting an energy many thousand times greater than at present, would have appeared preposterous and incredible, and would have * Sui Testacci della Sicilia, DONATJ.-UUFFON, 47 required a hundred violent hypotheses; but we are so unacquainted with the true sources of subterranean disturbances tl~at thei~· form~r vio:ence may in theory be multiplied indefi~ mtely, without Its bemg possible to prove the same manifest contradiction or absurdity in the conjecture. For this reason, perhaps, Moro preferred to derive the materials of the strata from. volcanic ejections, rather than from transportation by runnmg water. Marsilli, in the work above alluded to by Generelli, had been prompted to institute inquiries into the bed of the Adriatic, by discovering in the territory of Parma, (what Spada had observed ncar Verona, and Schiavo in Sicily,) that fossil shells were not scattered through the rocks at random but disposed in regular order, according to families. But with a view of throwing further light upon these questions Donati m. . 175 0, u?dertook a more extensive investigation of th' e Adri-' atic, and discovered, by numerous soundings, that deposits of sand, marl, and tufaceous incrustations, most strictly analogous to those of the Subapennine hills, were in the act of accumulating there. He ascertained that there were no shells in some of the submarine tracts, while in other places they lived together in families, particularly the genera Area, Pecten, Venus, M~rex, and some others. A contemporary naturalist, Baldassal'l~ had shewn the same grouping of organic remains in the tertiary marls of the Sienese territory. Buffon first made known his theoretical views concerning t?e for~er changes of the earth in his Natural History, pubhshed m 1749. His opinions were directly opposed to the systems of Hooke, Ray, and Moro, for he attributed no influence whatever to subterranean movements and volcanoes but returned to the universal ocean of Leibnitz. By this aq~eous envelope the highest mountains were once covered. Marine CUrt'~nts then acted .violently, and formed horizontal strata, by washmg away land m some parts, and depositing it in others; they also excavated deep submarine va11eys. He was greatly at a Joss for some machinery to depress the level of the ocean, and cause the land to be left dry. He therefore speculat~d on tl~e possibility of s~bterranean caverns having opened~ mto wluch the water entered, so that he involuntarily approximate~ to Hooke's theory of subsidences by earthquakes. |