M I C R O S C O, E I C A L E S S A Y-S. 



The corona is not fo uniform as the other parts, nor is it ' 

 conftituted ex a 61:1 y fimilar in all trees. It is placed between the 

 pith and wood in all vegetables, forming a ring, whole outline is 

 more or lefs regulated. The general circle is cellular, compofed 

 of blebs and veffels, like the bark and the rind, and is perfectly 

 fimilar to them, only that at different diftances oblong clu Iters 

 of different veffels are placed amongft it. Thefe clutters are 

 ufually eight or ten in number, and give origin to the angles of 

 the corona. They are not uniform, or of one kind of veffels, as 

 in the bark, but each has two diflincT: forts,- the exterior one 

 a'nfwering to the blea, and the interior to the wood of trees ; 

 and within each of thefe are difpofed veffels not unlike thofe 

 in trie blea and wood, though often larger than they are foand 

 - in thofe parts. 



Thus each duller is compofed of all the eflential parts of the 

 fucceeding branch, and the intermediate parts of the circle are 

 abfolutely bark and rind ; they are ready to follow and clothe 

 the duffer when it goes off in the form of a fhoot, becaufe it will 

 then need their covering and defence, though, in it's prefent in- 

 clofed flate, it does not. It is from this conftruclion that a tree is 

 ready at all times, and in all parts, to fhoot out branches, and 

 every branch in the fame manner to fend out others j for the 

 whole trunk, and the branch in all it's length, have this courfe of 

 eflential veffels ready to be protruded out, and the proper and 

 natural integuments as ready to cover them. In fome trees thefe 

 parts are more evident, in others more ob feu rely arranged. Dr. 

 Hill fays, the bocconia, or parrot-wood of the Weft-Indies, and 

 the 'greater celandine, are proper fubjecls for opening this great 



myfiery 



