THE THEORY AND PRACTICE OF WORKING PLANS 



73 



(c) Value and Application. — The greatest advantage of Von 

 Mantel's formula is its utter simplicity; for it requires only 

 the total volume and the rotation. It is thereby adapted to the 

 most meagre data. 



Its disadvantages are: i. That it assumes a definite rotation 

 which is altogether impossible in view of the disturbing emer- 



15 



25 



35 



45 



55 



65 



75 



85 



95 



gencies which always arise. 2. While it does automatically 

 reduce any surplus or deficit in the growing stock, it requires 

 unduly long to do so. The annual cut is apt to be over- 

 conservative. 



Its use is, therefore, restricted to determining the cut pro- 

 visionally before detailed data can be obtained, and as a check 

 on the results obtained by other methods. 



