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On the Dry Rot. 179 
dled their trees in the summer; and further, that they let oom 
stand until the dry rot developed itself in the alburnum. 
If the timbers in ancient buildings were examined closely, the 
Season in which the trees were killed may be pretty correctly as- 
certained, for if cut in the summer, the powder-post will invaria- 
bly be found on the alburnum, and if that has disappeared, there 
will be always some appearance on the heart-wood, that will 
show that the disease has been there, but never within its surface, 
and the same is true as regards the dry rot. The result of the fol- 
lowing experiments will prove these facts. Cut two saplings, 
(no matter how small, if there be any heart-wood in them, ) one in 
June, and the other in December. 'Take one piece of a conven- 
ient length from each, and put them into the garret, and one from 
each and put them into the cellar. In about three years it will 
be perceived that the powder-post has appeared on the alburnum 
of the one cut in June; and in the heart-wood of the one cut in 
December, of those in the garret ; and that the dry rot has made 
its appearance on the alburnum of the one cut in June, and in the 
heart-wood of the one cut in December, of those in the cathe. By 
these experiments it can also be seen, that the cause which pro- 
duces dry rot, under other circumstances will produce powder- 
Although it is my opinion that June is the best time to cut 
timber to make it last the longest, yet it is probable that there 
would not be much difference in its lasting, if it be cut in either 
of the summer months. But there is a period in which, if timber 
is cut, the dry rot, or under other circumstances the powder-post, 
will appear both in the heart-wood and the alburnum, at the same 
time, although I have seen but few cases of it, and in those cases 
I had no knowledge of the time of the death of the trees; but I 
judge it is either late in the fall, or early in the spring, from the 
circumstance of the bark being closely attached to the alburnum. 
It would be satisfactory to know the exact period when the 
tree was killed, from which the block was taken that is now un- 
dergoing the severe ordeal of the fungus pit at Woolwich, Eng- 
land ; and if that cannot be ascertained, whether the dry rot first 
made its appearance in the alburnum or the heart-wood, of its 
fellow that was destroyed by it; and also to have a block taken 
from a perfectly healthy tree killed in June, with the alburnum 
removed and the surface of the heart-wood left perfectly smooth, 
and without any seasoning put into the pit. 
