CHAPTER VII. 



THE " DRY-ROT " OF TIMBER. 



IT has long been known that timber which has been 

 felled, sawn up, and stored in wood-yards, is by no 

 means necessarily beyond danger, but that either in 

 the stacks, or even after it has been employed in 

 building construction, it may suffer degeneration of a 

 rapid character from the disease known generally as 

 "dry-rot." The object of the present chapter is t< 

 throw some light on the question of dry-rot, by sum- 

 marizing the chief results of recent botanical inquiries 

 into the nature and causes of the disease or, rather, 

 diseases, for it will be shown that there are several 

 kinds of so-called " dry-rot. " 



The usual signs of the ordinary dry-rot of timber 

 in buildings, especially deal-timber or fir-wood, are as 

 follows. The wood becomes darker in colour, dull 

 yellowish-brown instead of the paler tint of sound 



