ON PEUNING. 71 



tte most injurious consequences, not only on 

 account of the diminished means of forming 

 timber occasioned by the number of leaves 

 being lessened, and the incurable wounds 

 inflicted, but also on account of the mecha- 

 nical disadvantages a tree has when deprived 

 of its balancing boughs in resisting the force 

 of the winds. 



" If we examine the effect of the wind on 

 a perfect tree standing by itself, we shall be 

 convinced how necessary the lower boughs 

 are, and how impossible it is to cut or prune 

 any part away without committing injury. A 

 tree perhaps one hundred feet high, and nearly 

 as wide across the lower branches, and co- 

 vered with innumerable leaves, must have a 

 wonderful power to resist or to evade a strong 

 wind; its powers of evading are admirable. 

 The leaves, for instance, are fixed on foot- 

 stalks that give way, and the edge of the leaf 

 only is presented to the wind ; were it not for 

 this provision, the strongest oaks, when in leaf. 



