66 



the earth on the upper sides ? The 

 largest growth on branches is on the 

 sides on which they have the most 

 spray or small twigs ; so that branches 

 which grow diagonally upward, having 

 the greater quantity of spray on the out- 

 side, on account of the greater quantity 

 of light, will also have their annual rings 

 of wood largest on the outside from the 

 descending sap of the spray depositing 

 most freely on its own side. 



But the stem of a tree will be ex- 

 actly like a river ; its size will depend 

 on the number and size of the branches 

 which fall into it ; and it will be seen 

 to increase below and to decrease above 

 the spot where each of its branches join 

 it. It is beautifully ordained, that no 

 branch can grow above without depositing 

 below strength to support itself. 



Fir trees, which are very regular in the 

 size and position of their branches, are also 

 very regular in the tapering of their stems; 



