19^ PHILOSOPHICAL TRANSACTIONS. [aNNO 1 705. 



Frg. 14 represents a little slice of the lime-tree wood, in which we may count, 

 in nine several places, the horizontal vessels or canals that are cut across, and 

 which canals are situated between the small ascending vessels, which for the 

 most part nourish the wood. Now between the horizontal vessels and canals in 

 the wood and in the bark there is no difference, but in the ascending vessels 

 and the bark there is, for they are of such a disposition as the horizontal vessels 

 which are in the wood and the bark ; and thus they agree with those vessels 

 represented in fig. 13, by ns or pa. Now if we find that the horizontal vessels 

 or canals, as well in the wood as in the bark, are of one contexture ; and that 

 the ascending vessels in the bark of a lime-tree are also of the same ; we may 

 more firmly conclude, that the bark is produced from the wood, and not from 

 the root. 



I have turned my thoughts again upon the consideration of cork, which is 

 said to grow as the bark of a tree, on a kind of oak* in Spain; which if so, I 

 imagine that the burning which we perceive in the flakes of cork, is done by 

 two hot iron plates, in order to make it flat and straight. I took then one of 

 those pieces of cork which are cut into stoppers for bottles, as is represented 

 in fig. 1 5. In which we must suppose that bg is the part that lay next the tree, 

 and that e was the outside of the same. 



Between ghike are five distinct divisions, running across from p to d, which 

 is the part that surrounded the tree, and from whence I conclude, that the cork 

 was arrived to such a thickness in 5 years time, for each streak denotes the 

 growth of that year. There are also four distinct dark streaks, of which gi is 

 the middlemost, which I supposed were large canals. We must also conclude 

 that the length of all corks (in order to prevent either moisture or air from 

 passing through them) must be according to the length of the cork as it grows 

 on the tree, and so that part of the cork represented by abc was the lowermost 

 part, and depg was the uppermost or near the uppermost, according to its situa- 

 tion upon the tree. For further satisfaction, I cut a little piece of a cork, as 

 from G, where we may suppose that it was joined to the tree, cutting it after 

 such a manner, that the cut of the knife went from g to h, and having placed 

 it before the microscope, I perceived all the canals so situated, as if they came 

 out of the wood, without discovering in the least any ascending vessels, though 

 I cut it ever so often ; from whence I must again conclude, that the growth 

 of the cork proceeds from the wood. 



Fig. l6 shows a small particle of a cork, as it was cut off^ between g and h, 

 of which we must suppose lmn to be the part next the tree, and so the vessels 

 or canals, by which it receives its increase, run horizontally, as from l to a, 



* Cork is the bark of the quercut Buber. Linn. j ^J^ jiwd m. 



