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vigour. And not only so, but we are ta 

 consider, that any branch so displaced is 

 a certain degree of obstruction removed, 

 so far as the quantity of branches is more 

 than necessary to the feeding of the stem. 

 Whatever causes an increase in the vi- 

 gour of the top of a tree, must do the 

 same to the roots, which are in some 

 3ense no other than the mouths of the 

 plant. The branches would not be seen. 

 extending themselves, quicker and fur- 

 ther than ordinary in the air, if the root 

 had not previously done the same in the 

 earth. They are, by such means, not 

 only increased in quantity, but have ad- 

 ditional pasture, where they collect an 

 increased portion of nutriment, which, 

 converted into sap, will ascend to the 

 head, and in doing so enlarge the ves- 

 sels or conductors. An increased quan- 

 tity, with an amended circulation of 

 sap, amounts to what may not unaptly 

 be denominated, an improved consti- 

 tution ; which repeated attention could 



