LOG MEASURE 213 



In continental Europe and the Philippine Islands, the cubic meter 

 has been established as the standard unit for the measuring of logs and 

 timber. 



In recent years, board measure has also been used as a unit of volume 

 for logs. When so applied, the measure does not show the entire con- 

 tent of the log, but the quantity of lumber which, it is estimated, may be 

 manufactured from it. The number of board feet in any given log is 

 determined from a table that shows the estimated number which can 

 be taken out from logs of different diameters and lengths. Such a 

 table is called a log scale or log rule, and is compiled by reducing the 

 dimensions of perfect logs of different sizes, to allow for waste in manu- 

 facture, and then calculating the number of inch boards which remain 

 in the log. 



The amount of lumber that can be cut from logs of a given size is 

 not uniform, because the factors which determine the amount of waste 

 vary under different circumstances, such as the thickness of the saw, 

 the thickness of the boards, the width of the smallest board which may 

 be utilized, the skill of the sa^vyer, the efficiency of the machinery, the 

 defects in the log, the amount of taper, and the shrinkage. This lack 

 of uniformity has led to wide differences of opinion as to how log rules 

 should be constructed. There have been many attempts to devise 

 a log rule which can be used as a standard, but none of them will meet 

 all conditions. The rules in existence have been so unsatisfactory that 

 constant attempts have been made to improve upon them. As a result 

 there are now actually in use in the United States 40 or 50 different log 

 rules, whose results differ in some cases as much as 120 per cent for 

 20-inch to 30-inch logs and 600 per cent for 6-inch logs. Some of these 

 are constructed from mathematical formulae ; some by preparing dia- 

 grams that represent the top of a log and then determining the amount 

 of waste in sawdust and slabs ; some are based on actual averages of 

 logs cut at the mill ; while still others are the result of making correc- 

 tions in an existing rule to meet special local conditions. 



The large number of log rules, the differences in their values, and the 

 variation in the methods of their application have led to much confusion 

 and inconvenience. Efforts to reach an agreement among lumbermen 

 on a single standard log rule have failed so far. A number of states 

 have given official sanction to specific rules ; but this has only added to 

 the confusion, because the states have not chosen the same rule, so 



