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Show 72 ERA. OF THE S'UPERFICFA.L FORMATlONI .. A 11 of these speculations are as yet far too deficien1 in thcts, to be of much value ; and I must freely own that,. for one, I attach little importance to them. All that we can legitimately infer from the diluvium is, that the northern parts of Eqrope and America were then under the sea, and rhat a strong current set over them. Connected with the di1uvi urn is the history of ossife?"OlUI cave1·ns, of which specimens singly exist at Ki1·kdale, in Y01·kshire, Gaile.nreuth in Franconia, and other places. T hev occur in the calcareous strata, as the great caverns generally do, but have in all instances been naturally closed up till the 1·ecent period of their discovery. , Th\3 floors are covered with what appears to be a bed. of the diluvial clay, ove1· which rests a crust of stalagmite, the result of the droppings from the roof since the time whe:n the clay-beu was laid down. In the instances above specified, and several others, there have been found, under the clay-bed, assemblages flf the bones of animals, of many various kinds. At K.irkdale, for example, the 1·emains of twenty-four species were ascertained-namely, pigeon, lark, raven, duck, and partridge; mouse, water-rat, rabbit, hare, deer, (three species,) ox, horse, hippopotamus, rhinoceros, elephant, weazel, fox, \Volf, bear, tiger, hyena. From many of the bones of the gentler of these animab being found in a broken state, it is supposed that the cave was a haunt of hyenas and other predaceous animals, by which the smaller ones we1·e here consumed. This must have been at a time antecedent to the submersion which :>roduced the diluvium, since the bones are covered by a bed of that formation. It is in1possible not to see here a very natural series of incidents. First, the cave is frequented by wild beasts, who make it a kind of charnel- . house. Then, submerged in the cunent which has been spoken of, ~t receives a clay flooring from the waters containing that matter in suspension. Finally, raised from the water, but V{ith no mouth to the open air it remain9 unintruded on for a long series of ages, during which the clay flooring receives a new calcareous covering from the droppings of the roof. Dr. Buckland, who examined and described the Kirkdale cave, was at first of opinion that it presenter! a physical evidence of the N oachian deluge; but he afterwards saw reason to consider its phenomena as of a time far apart from that event, which rests on evi dence of an entirely different kind. CO.l\!MENCEMENT OJ" PRESENT SPECIES. 73 Our attention is next drawn to the erra~ic b~ocks or ooulde1.-s, which in many parts of the earth are thicldy strewn over the surface, pa·rticularly in the north of Europe. Some of th~se blocks are many tons in weight, yet <:.t.r~ clearly ascert~Ined to have belonged originally to situation_ s at a great d1stance. Fragments, fc: example, of the granite ?f Shap Fell are found in every direction around, to the d1.stance of fif~y miles, one piece being placed high upon Cnffel Mounta1n, on the opposite side of the Sol·.vay estuary; so also are fragments of the Alps found far up the slopes of the Jura. There are even blocks on the east coast of England, supposed to have travelled from Nor\ Vay. The only rational conjecture which can be formed as to tl~e transp?rt of such massses from so great a distance, Is one which presumes them to have been carried and dropped by icebergs, while the space between their original and final sites was under ocean. Icebergs do even no~ carry off EiUch ~a~ses ~rom . the polar coasts, ·which, f~lhng when the retaining Ice melts, 1nust take up situations at the bottOin of the sea, analogous to those in which we find the erratic blocks of the present day. As the diluvium and erratic blocks clearly suppose one last l?ng subme~sion of the surface, (last, geologically spea~Ing,) there Is another set of appearances which as rnanifest.ly show the steps by which the land was made afterwards to reappear. These consist of terrac€s, which have been detected near, and at some distance inland from the coast of Scandinavia, Britain, America and other regi. o~s; being ev~dently ancient beaches, or' platforms, on whiCh the margin of the sea at one time rested. They have been observed at different heights above the present sea-level, from twenty to above twelve hundred feet · and in many places they are seen rising above each oth~r in successiOn, to the number of three, four, and even more. T~e s~oo_th ~atness of these terraces, with generally a sl!ght Inclination tow~rds the ~ea, the sandy composition Of manr of them, ~nd, Ill some Instances, the preservation of. man~e. shells In the ground, identify them perfectly With ~xtstn~g. sea-beaches, notwithstanding the cuts and scooptngs which have every here and there been effected In them by water-courses. The irresistible inference from the phenomen~ is, that the highest was first the coast-line ; then an elevation took place, and ~he second highest became so, the first being now raised into the air and thrown |