On the Dry Rot 179 



died their trees in the summer ; and further, that they let them 

 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 cellar. By 

 these experiments it can also be seen, that the cause which pro- 

 duces dry rot, under other circumstances will produce powder- 

 post. 



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. 



