67 



but if the lower branches are cut, or killed 

 by their neighbours, in the course of time 

 the branchless part of the stem loses its 

 tapering form. And the stem of any tree 

 which has been long bare of branches shows 

 like the Lower Nile, — unvarying in size, 

 because without a tributary. It will appear 

 to the eye as large above as below ; for 

 as regards the horizontal girthing, the 

 head deposits equally down the whole 

 extent of the bare stem below it ; that 

 is, though the over deposit of growth 

 from over large branches on their own 

 side of the stem may tend to make the 

 stem oval instead of round, this will 

 make no difference to the comparative 

 horizontal girthing of the tree at dif- 

 ferent heights. And if equals are an- 

 nually added to unequals, though the 

 original absolute inequality will for ever 

 remain the same, the relative inequality 

 will annually decrease ; and the stems of 

 trees which have been long branchless 



E 2 



