( 333 ) 



can make but little impreflion on them, and the reafon * of this 

 ftrength and iirmnels in oak timber has been explained by me in 

 another place. 



Moreover, thofe pieces of wood which are left with the bark on, 

 are more obnoxious to be injured by maggots than thofe which are 

 firipped of it, becaufe, as I conceive, the maggots, while young, 

 are more able to gnaw into the bark than into the wood itfelf ; but 

 when they have fed upon the bark for fome time, they by degrees 

 grow flronger, and are better able to gnaw the wood : of this we 

 have a proof in balkets, which are much lefs liable to be injured by 

 thefe maggots when made of white wauds than of thofe which 

 have the bark on. 



* Vol. I. p. 5 and 6. 



