QUANTITY INCREMENT. 



183 



or 

 and 



CH+I = (n + 1) m n+l -nx m n , 



c a+1 = nx m n+l + m n+l -nx m n , 



CH+I ~ w+i = n (m n+1 - m n ) . 



It follows that if m n+l ^,m n , then also c n+1 ^.w n+1 ; and if 

 m n+l = m n , then also e n+1 = w n+1 , as it was proposed to prove. 



(4) When the mean annual increment culminates, the 

 current annual increment must, naturally, already be 

 past its maximum, and be falling ; hence the former 

 culminates later than the latter. During the inter- 

 mediate period between the two culminations, the 

 mean annual increment is still rising, whereas the 

 current annual increment is already falling. 



Example : 



Or graphically represented : 



1-00 



8c 



.0 

 40 



4 



Fig. 43. 



