325 
these functions could take place. They in turn were denuded of their 
bark covering, one after the other, at intervals, according as the newly 
formed wood on the pillar first laid bare had made a junction with the 
lower lip of the cut, thus keeping up communication for the circulation 
of the sap. In this way every organ of the tree, over nearly a foot of its 
bole, was destroyed and again renewed, without killing it, or even ar- 
resting growth to any visible extent. It continued to unfold its leaves 
at the proper season, and produce new wood as other trees of the same 
kind did, with this difference only, that about four feet of the apex of 
the stem died. 
My object in continuing the experiment was two-fold :—First, to 
prove whether the tree would continue to live ; and, if so, whether any 
visible effects on its growth would result. Secondly, to ascertain, if 
possible, how far the wood continued dead towards the apex of the bole 
from the spot where the operation took place. 
With respect to the former, I can now state that the wounded por- 
tion of the stem is nearly healed over, with the exception of one hole, 
about two inches wide, which is partly filled with the debris of the de- 
caying wood, and out of which moisture constantly oozes; but otherwise 
the tree is quite healthy, and the only visible effect produced by the 
mutilation is, that of causing it to leaf and flower a little earlier than 
other trees of the same kind near it do. I could not ascertain the second 
object without destroying the tree, which would have defeated the first, 
—consequently, similar experiments had to be made on other trees, the 
results of which I now proceed to lay before the Academy. The figures 
in Nos. 1 a@ and 6 of the diagrams correspond with the specimens ope- 
rated on, and now on the table, which are transverse sections, cut at 
} 
A ; 
iN 
ype 
i 
No. 1 a. No. 1 8. 
different heights above the place where the borings were made through 
the bole. No.-16 was cut 5 feet above it, and where the dead wood 
had greatly decreased in diameter, but it continued so, still farther 
decreasing 3 feet higher up the stem, where it commingled with 
