Ill 
of the Bark of Trees. 
the bark between them becomes compressed and inactive; 
no pedestal is in consequence formed, and the attachment of 
such a branch to the stem becomes extremely feeble and in- 
secure.* Instead of the reproduced buds of the preceding 
experiment, buds were inserted in the foregoing summer, or 
attached by grafting in the spring ; and, when these succeeded, 
though they were in many instances taken from trees of dif- 
ferent species, and even of different genera, no sensible diffe- 
rence existed in the vessels, which appeared to diverge into 
the bark of the stock, from these buds and from those repro- 
duced in the preceding experiments. 
It appears, therefore, probable, that a pulpous organisable 
mass first derives its matter either from the bark, or the 
alburnum ; and that this matter subsequently forms the new 
layer of bark ; for, if the vessels had proceeded, as radicles, ■f 
from the inserted buds, or grafts, such vessels would have 
been, in some degree, different from the natural vessels of the 
bark of the stocks ; and it does not appear probable, even 
without referring to the preceding facts, that vessels should 
be extended, in a few days, by parts successively added to their 
* The advantages, which may be obtained by pruning timber trees judiciously, 
appear to be very little known. I have endeavoured to ascertain the practicability of 
giving to trees such forms as will render their timber more advantageously conver- 
tible to naval or other purposes. The success of the experiments, on small trees has 
been complete, and the re*ults perfectly consistent, in every case, with the theory I 
have endeavoured to support in former memoirs ; and I am confident, that by appro- 
priate management, the trunks and branches of growing trees may be moulded into 
the various forms best adapted to the use of the ship-builder; and that the growth of 
the trees may at the same time be rendered considerably more rapid, without any 
expense or temporary loss to the proprietor, 
f Darwin’s Phytologia, 
