292 THEORY of the EARTH. 



table productions of the prefent earth, however deep they may 

 be found buried beneath its furface, and however ancient they 

 may appear, compared with the records of our known times, 

 are new, compared with the folid land on which they grew ; 

 and they are only covered with the produce of a vegetable 

 foil, or the alluvion of the prefent land on which we dwell, 

 and on which they had grown. But the foflil bodies which 

 form the prefent fubjecl of enquiry, belonged to former land, 

 and are found only in the fea-born ftrata of our prefent earth. 

 It is to thefe alone that we appeal, in order to prove the cer- 

 tainty of former events. 



MINERALIZED wood, therefore, is the object now enquired 

 after ; that wood which had been lodged in the bottom of the 

 fea, and there compofed part of a ftratum, which hitherto we 

 have confidered as only formed of the materials proper to the 

 ocean. Now, what a profufion of this fpecies of foflil wood 

 is to be found in the cabinets of collectors, and even in the 

 hands of lapidaries, and fuch artificers of polifhed flones ! In 

 fome places, it would feem to be as common as the agate. 



I SHALL only mention a fpecimen in my own collection. It 

 is wood petrified with calcareous earth, and mineralized with 

 pyrites. This fpecimen of wood contains in itfelf, even with- 

 out the ftratum of ftone in which it is embedded, the mod 

 perfect record of its genealogy. It had been eaten or perfo- 

 rated by thofe fea-worms which deftroy the bottoms of our 

 mips. There is the cleareft evidence of this truth. Therefore, 

 this wood had grown upon land which ftood above the level of 

 the fea, while the prefent land was only forming at the bottom 

 of the ocean. 



WOOD is the moft fubftantial part of plants, as {hells are the 

 more permanent part of marine animals. It is not, however, 

 the woody part alone of the ancient vegetable world that is 

 tranfmitted to us in the record of our mineral pages. We 

 have the type of many fpecies of foliage, and even of the 



moft 



