50 STATE BOARD OF FORESTRY. 



originally scaled by the Spaulding Log Rule, or any other rule of 

 similar form, where b has a value greater than 0, the transformation of 

 the total scale to a total based on a log rule of the form 



n 7) 2 

 (1 c) = B.M. would be impossible unless the sum of the 



4 X 12 



lengths of all logs in the trainload be known. Suppose, for example, 

 the aggregate scale of a trainload of logs was 250,000 board feet by the 

 Spaulding Log Eule, and the sum of all log lengths in the load was 

 12,000 linear feet, and it was required to know the total scale when 

 based upon the Square of Two-thirds rule, the following operations are 

 all that would be necessary : Add to 250,000 twice the sum of all log 

 lengths, which would be 24,000, divide by (1 .266) and multiply by 

 (1 .435). The resulting aggregate scale of the trainload of logs 

 based on the Square of Two-thirds rule would then be 211,000 board 

 feet, which is the same as would have been obtained had the Square of 

 Two-thirds rule been originally applied. 



