15^ The Natural Hiflorj Part IIL 



the like, being thereby protected in 

 great meafare from its Attacks ; it 

 paffing through thefe only in leffer 

 quantity, and that flowly and with 

 ^rMCc;^. difficulty fo that its Motion here 

 l^ejj^g j|njQj.g feeble and languid, the 

 Shells and other Bodies encloled i/i thefe 

 are ufually found very firm and entire^ 

 many of them retaining even their na- 

 tural Colours to this day, though they 

 have lain thus above four thoufand 

 years ; and may doubtlefs endure much 

 longer, even as long as thofe Strata^ to 

 which they owe their Prefervation , 

 fliall themfelves endure, and continue 

 entire and undifturbed : whilft thofe 

 which were lodged in Marie, Sand, 

 Gravel, and the like, more loofe and 

 ferviom Matter, are fb rotted and ^e- 

 cayed^ that they are now not at all, or 

 very clilxicukly, diftinguifliable from 

 the iVIarle, or other Matter in which 

 they lye. Not but that there are fbme- 

 times found, even in thele laxer Strata^ 

 Shells, Teeth , and other Bodies that 

 are ftill tolerably firm, and that have 

 efcaped pretty fafe ; but thefe are only 

 fuch as are of a more than ordinary 

 robufi and durable Conflitution, where- 

 by tliey were enabled the better to 



With- 



) 



