DISCUSSION OF LOG RULES. 13 



(.048D 2 3)L = 'B.M.. = Total sawed out as shown by the Scrib- 



ner Log Eule. 



- L = total contents = .0655DIL 



12 



.0655D 2 L- (.048D 2 ~ 3)L = waste [(.0655 - .048)D 2 + 3]L 

 = (.0175D 2 



100 = % waste based on total sawed out as shown 



(.0 181) - 3) L by s cr ibner Log Rule. 



.0175D 2 + 3 

 ".048D 2 3 



When D = 10", the waste allowance based on the total sawed out 

 as shown by the Scribner Log Rule = ( Formula does 

 not apply below 14"). 



When D = 20", the waste allowance = 61.8%. 



"When D = 30", the waste allowance = 46.7%. 



When D = 40", the waste allowance = 42.0%. 



When D = diameter in inches for very large logs, waste allow- 

 ance = 36.5%. 



The Doyle Log Rule. 



The Doyle Log Rule is used throughout the entire country and is the 

 statute rule of Florida, Louisiana and Arkansas. It is constructed 



//) 4\ 2 

 from the formula - - J Z-- B.M., which is stated as follows: 



Deduct 4" from the diameter of the log as an allowance for slabs; 

 square one quarter of the remainder and multiply the result by the 

 length of the log in feet. No mention is made in this rule of a sawdust 

 allowance. If four inches from the diameter of the small end is the 

 slab allowance, the sawdust allowance must be the difference between 

 the solid contents in board feet remaining after the slab allowance has 

 been made and the contents shown by the rule. The determination of 

 sawdust allowance follows : 



/D 4V 



1 L = B.M. = volume in board feet, as shown by the 



Doyle rule, of log D inches in diameter at small end 

 inside bark and L feet long. 



L volume in board feet of log D inches in diame- 

 ter inside bark at small end L feet long with 

 waste allowance for slabs but none for sawdust. 



L { - - j L = sawdust allowance for log D 



.7854 (D 4) 2 (V 4\ 2 



/ inches in diameter and L feet long. 



.7854 (D 4) 2 T (D 4 t 



lj 



12 



X 100 = sawdust allowance for 



.7854 (D - 4) ' i O g 2) inches in diameter and 



12 L feet long expressed in per 



cent of volume in board feet left 



= 4 5<y after slab allowance has been 



.0655 made 



318022 



