5'9 



of timber, as it is usually accompanied 

 with the property of cleanness, or being 

 free from knots. When that is the case, we 

 say, a piece of timber is strong ; and it is 

 observable, that great lengths are seldom 

 used at once, but where considerable 

 strength is required. When the knots are 

 large, the wood cannot be strong. 



The difference in value between a clean 

 length of thirty feet, and another of eight, 

 the scantlings being the same, will be ve- 

 ry considerable to the carpenter, foot for 

 foot, in two points of view. The former 

 being applicable to so many more pur^ 

 poses than the latter, renders so much 

 less stock necessary. He may likewise 

 use all the former, without incurring any- 

 more waste, than he would do in using 

 the latter : — it is only the latter part that 



admits of any. Besides knots divert 



the grain of the wood in a greater or 

 less degree, according to their size. 



