OF NATURAL HISTORY. 517 



the affiftance of a heat fuperlor to that of the common atmofphere, 

 might not the ordinary methods employed for the recovery of drown- 

 ed perfons be affifted by the application of warm afhes or chalk ? 

 The. ftrudure of a fly and that of a man, it is allowed, are very dif- 

 ferent. But, in defperate cafes, when every other method fails, no 

 fafl; fhould be overlooked, and no analogy defpifed. 



Plants differ as much in the periods of their exiftence as animals. 

 Many plants perifli yearly ; others are biennial, triennial, &c. But 

 the longevity and magnitude of particular trees are prodigious. We 

 are informed by Mr Evelyn, that, in the bodies of fome Englifh 

 oaks, when cut tranfverfely, three, and even four, hundred rings of 

 wood have been diftinguifhed. A ring of wood is added annually 

 to the trunks of trees ; and, by counting the rings, the age of any 

 tree may be pretty exadly afcertained *. With regard to the mag- 

 nitude of oaks, fome of them are huge maflTes. Dr Hunter, in his 

 Notes upon Evelyn's Sylva, remarks, that none ' of the oaks men- 



* tioned by Mr Evelyn bear any proportion to one now growing at 



* Cowthorpe, near Wetherby, upon an eftate belonging to the Right 



* Hon. Lady Stourton. The dimenfions are almoft incredible. With- 

 ' in three feet of the furface, it meafures fixteen yards, and, clofe by 



* the ground, twenty-fix yards. Its height, in its prefent and rui- 



* nous ftate, (1776), is about eighty-five feet, and its principal limb 



* extends fixteen yards from the bole. — When compared to this, all 



* other trees are but children of the foreft f-' 



From the fads which have been enumerated, it appears, that all 

 animals, as well as vegetables, have ftated periods of exiftence, and 

 that their diffolution is uniformly accompliflied by a gradual harden- 

 ing: 



* See Evelyn's Sylva, page joj, 

 f Ibid, page 500. 



