RECENT LOG RULES. 



Henry S. Graves. 



It has been the custom in this country for a good many years 

 to express the contents of round log's in board measure, a unit 

 originally designed for manufactured lumber. Log rules are con- 

 structed to show the board contents of logs of different sizes. 

 These rules show really the amount of lumber, expressed in board 

 feet which it is estimated may be manufactured from logs. The 

 factors determining the amount of lumber that may be secured 

 from logs are exceedingly variable and hence it has not been 

 possible to construct a log rule that will satisfy every manufac- 

 turer. The result has been the production of a large number of 

 log rules, most of which have been used in actual business trans- 

 actions. 



From time to time there has been an agitation toward uni- 

 formity in log measure. These agitations have usually resulted 

 in the production of more rules. In 1900 the Woodsman's Hand- 

 book was published by the U. S. Bureau of Forestry. In that 

 book the writer brought together 43 different commercial log 

 rules for board measure used in this country and Canada. Per- 

 haps that work added to the interest in the subject. At any rate 

 the presentation of the great array of rules with their many 

 variations and deficiencies has not stopped the production of new 

 rules. Mathematicians have taken a hand and worked out rules 

 based on sound mathematics rather than on rules of thumb. The 

 Champlain Rule of Professor Daniels is a case in point — a rule 

 which seems thoroughly adaptable to practical conditions, but so 

 far very few manufacturers have adopted it, as far as the writer 

 is informed. This and Professor J. F. Clark's International rule 

 have been discussed in the writer's Forest Mensuration. Since 

 the appearance of that book in 1906 a number of new rules have 

 appeared whose review may be of interest. 



Massachusetts' Rule. In 1905 Mr. R. C. Hawley, then As- 

 sistant State Forester of Massachusetts, made a local study of the 

 volume of White Pine. The investigation comprised the con- 

 struction of a log rule from mill tallies. Over 1200 logs at 12 



