THE EARTH. ?7 



fossil-shells could not have been deposited in such quantities all a\ 

 once by the flood ; and I think, from the above instance, it is prettv 

 plain, that, howsoever they were deposited, the earth was coverea 

 with trees before their deposition ; and, consequently, that the sea 

 could not have made a very permanent stay. How then shall we ac- 

 count for these extraordinary appearances in nature ? A suspension 

 of all assent is certainly the first, although the most mortifying con- 

 duct. For my own part, were I to offer a conjecture, and all that has 

 been said upon this subject is but conjecture, instead of supposing 

 them to be the remains of animals belonging to the sea, I would con- 

 sider them rather as bred in the numerous fresh-water lakes, that, in 

 primeval times, covered the face of uncultivated nature. Some of these 

 shells we know to belong to fresh waters ; some can be assimilated to 

 none of the marine shells now known ;* why, therefore, may we not 

 as well ascribe the productions of all to fresh waters, where we do not 

 find them, as we do that of the latter to the sea only, where we never 

 find them ? We know that lakes, and lands also, have produced ani- 

 mals that are now no longer existing ; why, therefore, might not these 

 fossil productions be among the number ? I grant that this is making 

 a very harsh supposition ; but I cannot avoid thinking, that it is not 

 attended with so many embarrassments as some of the former, and 

 that it is much easier to believe that these shells were bred in fresh 

 water, than that the sea had for a long time covered the tops of the 

 highest mountains. 



CHAPTER VI. 



OP THE INTERNAL STRUCTURE OP THE EARTH. 



HAVING, in some measure, got free from the regions of conjecture, 

 let us now proceed to a description of the earth as we find it by ex- 

 amination, and observe its internal composition, as far as it has been 

 the subject of experience, or exposed to human inquiry. These in- 

 quiries, indeed, have been carried but to a very little depth below its 

 surface, and even in that disquisition men have been conducted more 

 by motives of avarice than of curiosity. The deepest mine, which is 

 tb at of Cotteberg in Hungary ,t reaches not more than three thousand 

 feet deep ; but what proportion does that bear to the depth of the ter- 

 restrial globe, down to the centre, which is above four thousand miles ? 

 All, therefore, that has been said of the earth, to a deeper degree, is 

 merely fabulous or conjectural ; we way suppose with one, that it is a 

 globe of glass ;| with another, a sphere of heated iron ; with a third, 

 a great mass of waters ;|| and with a fourth, one dreadful volcano ;fl 

 but let us at the same time show our consciousness, that all these are 

 but suppositions. 



Upon examining the earth, where it has been opened to any depth, 

 the first thing that occurs, is the different layers or beds of which it ii 



Hill's Fossils, p. 641. f Boyle, vol. iii. p. 240. J Buflui } Whigtan, 

 j| liurnfit. If Kirr.her 



