404 APPLIED SCIENCE 



used immediately in a warm room, and is to be kept warm 

 and dry, until treated with some sort of paint filler that will 

 cover the wood and prevent the penetration of moisture. For 

 instance, if a piece of kiln-dried wood is exposed to the air, 

 it will absorb moisture until it soon has the same amount 

 as before being dried. Soft lumber, such as pine, spruce, 

 hemlock, etc., may without serious harm be kiln-dried as 

 soon as cut from the log, but hardwood, such as oak, hickory, 

 etc., should be previously air-dried for at least one year. 

 Wood must be seasoned very carefully in order to obtain 

 the best results. Sometimes as much as 20 to 25% of the 

 seasoned lumber in a yard has been rendered unfit for use 

 by defects which had their origin in the drying process. 

 Hence the necessity of knowing the right method of drying 

 wood. 



449. Classification of Sources of Lumber. The United 

 States produces many varieties of lumber. The following 

 list shows in brief form the particular sources of the various 

 types. 



450. Yellow Pine. Yellow pine lumber, of which there are 

 many varieties, is produced chiefly in the southern states. The 

 principal kinds of yellow pine are : 



1. North Carolina pine, from Virginia, North Carolina, and 

 South Carolina. 



2. Long-leaf pine, commonly called hard pine and Georgia pine, 

 from the Gulf states. 



3. Loblolly pine, generally called short-leaf, old-field, rosemary, 

 or Virginia pine, from Virginia, North Carolina, South Carolina, 

 Arkansas, the Gulf states, and Georgia. 



4. Short-leaf pine, chiefly from Arkansas, Virginia, North 

 Carolina, South Carolina, Louisiana, Mississippi, and to a less extent 

 from the other yellow pine states. 



