NATURAL HISTORY. 



317 



moredifficultlyaccounted for. Those 

 in Gcrmnny are found in caves. 

 The coast of Dalmatia is said to be 

 almost wiiolly formed of them, and 

 we know that this is the case wkh 

 a large portion of the rock of Gib- 

 raltar. 



If none were found in caves, but 

 in sohd masses covered with marl or 

 limestone, it would then give the 

 idea of their having been brought 

 together by some sti-ange cause, as 

 a convulsion in the earth, which 

 threw these materials over thorn ; 

 but this we can hardly form an idea 

 of; or if they had all been found ill 

 caves, we should have imagined 

 these cases were places of retreat 

 for such animals, and had been so 

 for some thousands of years: and if 

 the bones werethoseof carnivorous 

 animals and herbivorous, we might 

 have supposed that the carnivorous 

 had brought in many animals of a 

 jmallcr size which they caught for 

 food ; and this, upon the first view, 

 appears to have been the case with 

 those which are the subject of this 

 paperj yet when we consider that 

 the bones are principally of carni- 

 vorous animals, we are confined to 

 the supposition of their being only 

 places of retreat. If they had been 

 brought together byany convulsion 

 of the earth, they would have been 

 mixed with the surrounding mate- 

 rials of the mountains, v.hich dues 

 not appear to be the case ; for 

 although some are found sticking 

 in the sides of the caves incrusted 

 in calcareous matter, this seems to 

 have arisen from their situation in 

 the cave. Such accumulation would 

 have made them coeval with the 

 mountains themselves, which, from 

 the recent stateof thebonenlsiiould 

 very much doubt. 



The difference in the state of the 

 bones shews that there was probably 

 a succession of them for a vast series 

 of years ; for, if we consider the dis- 

 tance of time between the mostper- 

 fect having been deposited, which 

 we must suppose viere the last, and 

 the present time, we must consider 

 it to be many thousand years, and 

 if we calculate how long these must 

 still remain to be as far decayed as 

 some others are, it will require 

 many thousand years, a sufficient 

 time for a vast accumulation : from 

 this mode of reasoning, therefore, it 

 would appear that they were not 

 brought here at once in a recent 

 state. 



The animal earth, as it is called, 

 at the bottom of these caves, is sup- 

 posed to be produced by the rotting 

 of the flesh, which is supposing the 

 animals brought there with the flesh 

 on ; but I do conceive, that if the 

 caves had been stuffed with v,-hole 

 animals, the flesh could not have 

 produced one-tenth part of the 

 earth, and to account for such a 

 quantity as appears to be the pro- 

 duce of animals. I should supposeit 

 the remains of the dung of animals 

 who inhabited the caves, and the 

 contents of the bovv-els of those they 

 lived upon. This is easily con- 

 ceived from knowing that there is 

 something similar to it, in a smallef 

 degree, in many caves in this king- 

 dom, which are places of retreat 

 for bats in the winter, and even in 

 the summer, as tl.eyonly go abroad 

 in the evening; these cavts have 

 their bottoms covered with animal 

 earth, for some feet in depth, in all 

 degrees ofdecomposition, tlielovver- 

 most the most pure, and the upper-' 

 mostbut liitlechunged, with all the 

 intermediate degrees : in which 



cave? 



