42 STATE BOARD OF FORESTRY. 



logs of different sizes, since the underlying principles are not the same. 



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In the case of the standard rule based upon - = V, V is directly 



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proportional to the square of the diameter of the log and also directly 

 proportional to its length, whereas a log rule based upon correct prin- 

 ciples has the volume in board feet vary directly as the diameter minus 

 a constant squared, and directly as the length, with a taper correction 

 applied to at least 8' sections. 



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Standard log rules based upon - =V are, however, excellent rules 



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where a measurement proportional to the total contents of the log is 

 desired. Such measures are applicable to logs which are to be made 

 into pulp or whenever the total contents of the log is to be used. These 

 rules do not take taper into consideration. They can be reduced to 

 cubic feet by multiplying by a constant. 



