— 208 — 



AY Y 



From these figures, the characteristics of the curves Y, and — 



AflJ X 



are precisely the same as in the previous case (Plate XXXI.) Thus we 

 may determine the equation for Y as follows: — 



aix — 



Y=c'e 



a'x — 



b' 



or 



By applying the equation to the above given data we find: 

 log Y= 0.2761+0.02340;-^^'^ 



X 



In the following table the theoretical and experimental results are 

 compared : 



It will be seen that the agreement is precisely the same as in the 

 above illustration. 



B. Volume of Tree Bole 



In the previous part, we have explained the outline curve of a tree 

 bole expressed by the equation: 



