no 
Mr. Knight on the Formation 
dispersed themselves in different directions. Some descended 
perpendicularly downwards, whilst others diverged on each 
side, round the alburnum, with more or less inclination down- 
wards, and met on the opposite side of it. The same pulpous 
and cellular substance appeared to cover the surfaces of the 
bark and alburnum, when in contact with each other, as when 
detached ; and through this substance the ramifications of the 
vessels of the new bark extended themselves, appearing to 
receive their direction from the fluid sap which descended 
from the bark of the young shoots, and not to be, in any 
degree, influenced in their course by the direction taken by 
the cortical and alburnous vessels of the preceding year. 
Whenever the vessels of the bark, which proceeded from 
different points, met each other, an interwoven texture was 
produced, and the alburnum beneath acquired a similar orga- 
nisation : and the same thing occurs, and is productive of very 
important effects, in the ordinary course of the growth of 
trees. The bark of the principal stem, and of every lateral 
branch, contains very numerous vessels, which are charged 
with the descending true sap ; and at the juncture of the 
lateral branch with the stem, these vessels meet each other. 
A kind of pedestal of alburnum, the texture of which is much 
interwoven, is in consequence formed round the base of the 
lateral branch ; which thus becomes firmly united to the tree. 
This pedestal, though apparently a part of the branch, derives 
a large portion of the matter, annually added to it, fromffhe 
cortical vessels of the principal stem ; and thence, in the event 
of the death of the lateral branch, it always continues to live. 
But it not unfrequently happens, that a lateral branch forms 
4 very acute angle with the principal stem, and, in this case. 
