30 LOG RULES BASED ON CUBIC CONTENTS 



it would give accurate contents. This standard, in common with all 

 other cubic rules, is unsuited to the mcasiuement of the Ixjard f(!ot con- 

 tents of logs. 



33. The Blodgett or New Hampshire Cubic Foot. A cylindrical 

 unit has been adopted as the legal standard of the state of New Hamp- 

 shire. The statute reads, " All round timber shall be measured accord- 

 ing to the following rule. A stick of timber 16 inches in diameter and 

 12 inches in length shall constitute 1 cubic foot; and in the same ratio 

 for any other size and quantity." This arbitrary cubic foot contains 

 1.396 or approximately 1.4 cubic feet. 



The contents of logs is computed in Blodgett feet by the formula, 



This log rule is based on the middle diameter, and is therefore more 

 accurate in application than the Adirondack standards. The diameter 

 is measured by calipers and double width of bark is deducted (§84). 



This rule is a rough attempt to use the cubic foot, with an allowance for waste 

 in squaring round logs. But the per cent of waste by the rule is 28.4 per cent of the 

 cylinder, utilizing 71.6 per cent, while the area of an inscribed square is 63.6 per 

 cent of the circle with .36.4 per cent waste. The "squared" stick 1 foot long would 

 therefore have considerable wane. The Blodgett Rule was an attempt to secure a 

 standard which could be converted into board feet. The statute fixed the converting 

 factor as, 



100 Blodgett feet = 1000 board feet, or a ratio of 1 : 10 



But in scaling practice it was concluded that this ratio was unsatisfactory, and 

 gave too large a scale in board feet. So it was arbitrarily set in practice at 



115 Blodgett feet = 1000 board feet, or a ratio of 1 : ,S.7, 



when the rule was applied, as intended, to the middle diameter inside bark. Though 

 the scale in Blodgelt feet in either case was the same, the converted residt gave for 

 the ratio of 1 : 10, .59.7 per cent of the contents of the log in board feet, and for the 

 ratio 1 : 8.7, 51.9 per cent. Since 12 board feet = l cubic foot, 



and 



Likewise, 



and 



— =83g per cent of 1 cubic foot, 



.831 



^ = .597. 



1.396 



8.7 



— = 72 . 5 per cent, 

 12 



1.396 



