THE LEAF AS A BUILDER. 19 



the frequency of destructive frosts in early autumn, 

 and they maintain an equable climate in winter ; they 

 absorb and give out heat more slowly than the open 

 fields, and they act as a screen to land lying to the 

 leeward of blasting winter winds. When we interest 

 ourselves in tree life we begin to realize how great a 

 worker and builder the leaf is. It builds the tree, 

 and it works for our benefit. So intimately is it con- 

 nected with the tree life, that from it proceeds a tiny 

 channel, or nerve, so to speak, down the trunk to the 

 very root of the tree. John Kuskin, in Modem 

 Painters, vol. iv, speaks thus of the leaf -worker : " It 

 leads a life of endurance, effort, and various success, 

 issuing in various beauty ; and it connects itself with 

 the whole previous edifice by one sustaining thread, 

 continuing its appointed piece of work all the way 

 from top to root." 



