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BULLETIN 1136, U. S. DEPARTMENT OF AGRICULTURE. 



While it is not possible to lay down any hard-and-fast rules for 

 proper final moistures, the information in Table 16, based on average 

 conditions in the East and Middle West, may serve as a guide in the 

 drying of stock for specific purposes. 



Tabus 15. — Mean relative humidities at various points in the United States. 



City. 



Cleveland, Ohio.. 



Denver, Colo 



El Paso, Tex 



Galveston, Tex. . . 



Madison, wis 



Memphis, Tenn... 

 New Orleans, La.. 

 New York, N. Y.. 



Pensacola, Fla 



Phoenix, Ariz 



Portland, Oreg. . . 

 San Diego, Calif . . 

 Spokane, Wash... 

 Wilmington, N. C 



Mean relative humidity, per cent. 



Winter. Spring. Summer. Fall. Annual 



Table 16. — Final moisture content of stock for various uses. 



Final 

 moisture, 

 per cent. 



Furniture 5 to 7 



Interior woodwork 6 to 8 



Vehicle stock, except wheel and box parts 15 to 18 



Vehicle wheel and box parts 8 



Gunstocks 6 to 8 



Aircraft (Army) 8 



Aircraft (Navy) 12 



Outdoor sporting goods (bats, golf sticks, tennis rackets, polo mallets, 



etc.) 10 



Musical instruments 5 to 7 



Softwoods for long freight shipments 12 or less 



Miscellaneous outdoor material 12 



Note. — Thoroughly air-dried wood ranges from 12 to IS per cent moisture 

 content, depending on local climatic conditions. 



MOISTURE SPECIFICATION. 



Much of the trouble experienced in the use of lumber results from 

 improper seasoning, and many disputes arise from a misunderstand- 

 ing of the use or meaning of broad and loose terms, such as " kiln 

 dried " or " air dried," or even " thoroughly kiln dried " or " thor- 

 oughly air dried." These terms are so indefinite that they really 

 are without significance. There is now no universally accepted 

 standard moisture specification, and each purchaser must draw his 

 own. A moisture or seasoning specification is fully as important 

 as a grade specification — sometimes much more important — and it 

 is essential that the purchaser know that he is getting stock properly 

 seasoned for his use. 



A number of wood users throughout the country are now specify- 

 ing the amount of moisture that the stock shall contain at the time 

 of shipment or receipt, which is excellent in every way. It is not 



