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Show IMBEDDING OF ORGANIC REMAINS [Ch.XIII. · The same author observed in every cave examined by him in Germany, a deposit of mud or sand, sometimes with, and sometimes without, an intermixture of rolled pebbles and angular fragments of rock, and having its surface covered over with a single crust of stalagmite * · In the English caves he remarked a similar absence of alternations of alluvium and stalagmite. On the banks of the Meuse, however, at Chockier, about two leagues from Liege, a cavern has been recently discovered where there are three distinct beds of stalagmite, between each of which occur breccia and mud, mixed with some quartz pebbles, and the bones of extinct quadrupeds t· But this exception does not invalidate the generality of the phenomenon observed by the Professor, and of which we have as yet seen no satisfactory explanation. The principal cause we suspect to be, that if several floods pass at different intervals of time through any subterranean passage, the last, if it has power to drift along fragments of rock, will also tear up any alternating stalagmitic and alluvial beds that may happen to have been previously formed. Another cause may be, that in a country in which torrents and rivers are gradually deepening their channels, and cutting through masses of cavernous limestone (an excavating process which is most rapid during epochs of subterranean disturbance, when the levels of a dis· trict are altered), it will only happen once that the stream will break into hollows or fissures communicating with a certain series of caverns. When the erosive action has proceeded farther, and the river has sunk to a greater depth, the drainage of the country will be effected in a valley at a level inferior to that of the caves, and consequently no transported matter will afterwards be introduced into them. In the cave of Paviland, called Goat's Hole, on the coast of Glamorganshire, besides the bones of many extinct animals which occur in a mass of loam, a modern breccia has been formed, consisting of earth cemented by stalagmite, and con- * Rel. Dil. p. 108. t Joum. de Geologie, tome i. p. 266. July, 1830. Ch. XIII.] IN THE MUD OP CAVES AND FISSURES. ta,i ning marine-sh.e lls an.d bI' r d s , b ones, all of recent speC.i es. 'I he mouth of this cave IS from thirty to forty feet above high-water mark ' being si't ua t ed m· a 1o f ty cl I'f f of h.m estone, facm. g the estuary ~f the Severn, the waves of which, during great storms, occasiOnally dash into it. The left side of a human skeleton was also found here under a cover o f S·I X m· eh es o f earth. In a cavernous aperture leading from the roof of this cave to the face of the cliff was discovered a bed of brown e~rth, appa~·entl! derived from dust driven in continually by the wmd ; and m :his earth were the bones of various birds, of moles, wate~-rats, mice, and fish, and a few land-shells, all clearly the ~emams. of modern animals. Their presence in this almost maccessible spot can only be explained, says Dr. Buckland, " by referring the bones of birds, moles, rats, and mice, to the agency of haw~s, and the fish-bones to that of sea-gulls. The land-shells, whiCh are such as live at present on the rock witho~ t, rna~ ~asily have fallen in. Had there been any stalagmite umtmg these bones into a breccia, they would have a~or~ed a perfect analogy to the accumulation of modern bn·ds bones, by the agency of hawks, at Gibraltar*." The formation last alluded to occurs in perpendicular fissure~ at the north extremity of the rock of Gibraltar, where a reddish calcareous earth, containing numerous bones of 11 b' d · · sma Ir s, Is In the act of accumulating. Around these fissures a number of hawks nestle and rear their young in the breedingIs easo· n, and .t he bones are the remains .o f their food . M aJ. or ~rie m~ntiOns also a concretion in the rocks below King's Lmes, Gibraltar, co~sisting of pebbles of the prevailing cal;, areous rock, wherem, at a considerable depth under the sur· ace, part of a green glass bottle was found imbedded t. In .a cave of mountain-limestone at Burringdon in the Mendtp Hills, supposed to have been once used as :place of sepulture or refuge, human bones have been met with encrusted with stalactite, one of the sku1ls being filled with' this "' Buckland, Reliquim Diluvianoo,. p. 93. t Ib . p. 156. |