of the most refractory species has been 

 seasoned rapidly and with little dam- 

 age. Further work is being done to 

 perfect the process, which holds among 

 its possibilities the release of millions 

 of feet of little-used hardwoods for 

 Satisfactory service. 



Moisture control 



By whatever means it is accom- 

 plished, the seasoning process has one 

 main purpose — to fit wood for the mois- 

 ture conditions it will meet in service. 

 Kesearch is contributing to this end in 

 many ways. Instruments for the quick 

 determination of wood-moisture con- 

 tent have been developed and are now 

 manufactured and sold commercially. 

 By extensive field tests the principal 

 wood-moisture climates of the United 

 States have been charted as a guide to 

 seasoning for different regions. Defi- 

 nite moisture tolerances are thus deter- 

 mined for lumber according to localities 

 and uses and are finding an increasing 

 place in commercial specifications. 



The modern development of air- 

 conditioning systems for homes and 

 other buildings is introducing serious 

 winter problems of moisture transfu- 

 sion, sweating, and ice formation in 

 walls. A thorough investigation has 

 been undertaken to determine the rate 



M-31513-F 



Results o£ salt seasoning o£ swamp oak. 

 Upper group, salt seasoned; lower, speci- 

 mens from the same planks seasoned by 

 ordinary, methods. 



of moisture movement in wood wall 

 panels of different types at various 

 temperatures and humidities and the 

 effectiveness of sheet barrier materials' 

 in bringing it under control. 



23 



