450 



Forestry Quarterly 



of oak, beech and maple are prevailingly crooked and give a 

 smaller mill cut. 



The characteristic feature of the data from all mills is the rapid 

 increase in time for sawing which takes place when the logs become 

 smaller than 16 inches in diameter. In band operations, and the 

 same would undoubtedly hold true in circular operations of large 

 capacity, there is a gradual but very slight decrease in sawing time 

 for logs larger than 22 inches, the time practically being the same 



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 D/AMSrs/f OF LOG /A/ /A/C/f^S 



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for all diameters of the same length and kinds of wood of the same 

 hardness above 25 inches. However, in the case of portable cir- 

 cular mills with low power capacity the sawing time after reaching 

 a minimum again rises as the size of the logs increases on account 

 of insufficient motor power of the plant. The diameter at which 

 this rise occurs varies with the motive power of the plant, but is 

 lower for hardwoods than for softwoods. 



There is a marked difference also in the time required for sawing 

 logs of different lengths (Fig. 4) . The difference in time required 



