OF FOREST-TUEES. 



245 



Signior Stelluti, an Italian, has published a whole Treatise expressly to CHAP, IV. 

 describe this great curiosity : and there has been brought to our notice a ^•"■^"'"v"^*-' 

 certain relation of an Elm growing in Berkshire, near Farringdon, which 

 being cut towards the root, was there plainly petrified ; the like, as I once 

 myself remember to have seen in another tree, which grew quite through 

 a rock near the sepulchre of Agrippina (the mother of that monster Nero) 

 at the Baia by Naples, which appeared to be all stone, and trickling down 

 in drops of water, if I forget not. But while others have philosophized, 

 according to their manner, upon these extraordinary concretions, see what 

 the most industrious and knowing Dr. Hook, curator of this Royal So- 

 ciety, has with no less reason, but more succinctness, observed from a late 

 microscopical examen of another piece of petrified wood ; the descrip- 

 tion and ingenuity whereof cannot but gratify the curious, who will, by 

 this instance, not only be instructed how to make inquiries upon the 

 like occasions, but see also with what accurateness the society constantly 

 proceeds in all their indagations and experiments ; and with what can- 

 dour they relate, and communicate them. 



" It resembled wood, in that, 



" First, All the parts of the petrified substance seemed not at all dis- 

 " located or altered from their natural position while they were wood ; 

 " but the whole piece retained the exact shape of wood, having many 

 " of the conspicuous pores of wood still remaining, and shewing a mani- 

 " fest difference, visible enough between the grain of the wood and that 

 " of the bark, especially when any side of it was cut smooth and pohte ; 

 " for then it appeared to have a very lovely grain, like that of some 

 " curious close wood. 



" Next it resembled wood, in that all the smaller, and (if so I may call 

 " those which are only to be seen by a good glass) microscopical pores of it, 

 " appeared (either when the substance was cut and polished transversely, 

 " or parallel to the pores) perfectly like the microscopical pores of several 

 " kinds of wood, retaining both the shape and position of such pores. 



" It differed from Wood, 



" First, in weight ; being to common water, as 3^ to 1 ; whereas 

 " there are few of our English woods that, when dry, are found to be 

 " so heavy as water. 



Volume IL I i 



