28 BULLETIN 552, U. S. DEPARTMENT OF AGRICULTURE. 



Drying tends to render wood more or less brittle. Although the 

 strength of wood increases with its degree of dryness, yet wood which 

 has been dried and resoaked is less resilient than when green. There- 

 fore, where strength is the prime consideration, it is preferable not 

 to dry the wood beyond the degree at which it is to be used. The 

 final stage of kiln-drying is generally conducted at a humidity some- 

 what below the actual humidity that on long exposure would pro- 

 duce the same average moisture condition. This is done in order 

 to hasten the drying and to make it uniform throughout each piece. 



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