HARDWOOD RECORD 



27 



Common Sense as Applied to the Seasoning 



of Lumber 



Admittedly the thorough seasoning of lum- 

 Ijer, by either natural or artificial means, is 

 one of the most important problems encoun- 

 tered by the average lumber producer, Trhelher 

 he be manufacturing white pine, yellow pine, 

 gum, cypress, Pacific Coast woods or any of 

 the infinite variety of hardwoods. 



On the market today are a score or more of 

 dry kilns and dry kiln systems warranted to 

 thoroughly season lumber by artificial means 

 without injury to the appearance or strength 

 of the material, in time varying from twenty- 

 four hours to a week. Booklets describing 

 the various systems are replete with confus- 

 ing statements and chary of facts germane to 

 the subject, and are loaded down with alleged 

 technique and scientific data which are far 

 from accurate, but without exception all these 

 processes are warranted to season any and all 



kinds and thicknesses of lumber by identical 

 treatment. 



Dry kilns of various types have been built 

 for more than two decades and perhaps longer. 

 During that time certain improvements have 

 been made in them, but it is still a difficult 

 thing to find a dry-kiln user, whether a lum- 

 ber manufacturer or a furniture producer, 

 who is entirely satisfied with his kiln-drying 

 results. The consensus of opinion as analyzed 

 in various reports is that sometimes on cer- 

 tain kinds of stock the kiln gives good results, 

 but that a great part of the lumber that 

 comes through it is unsatisfactory by reason 

 of its not being properly dried or that it is 

 checked or honey-combed, or that the expense 

 is excessive. 



To take a common-sense view of the sub- 

 ject it would seem necessary to first demon- 



strate what the user of a system of drying 

 lumber is trying to accomplish. Primarily, 

 it miist be recalled that the moisture in green 

 lumber amounts to from twenty-five per cent 

 to sixty per cent of its total weight. Green 

 wood contains varying percentages of dif- 

 ferent substances — water, albumen, tannic 

 acid, sugar, starch, resin or other matter, and 

 the remaining portion of the material is wood 

 fiber or cellulose. 



It would also seem a matter of common- 

 sense that the only valuable portion of tree- 

 growth as a lumber material is the wood fiber, 

 and that the various substances which con- 

 tribute to the growth of the tree have no value 

 in the eventual utilization of the material. 

 If this be true, and there is no evidence to 

 the contrary, it would seem that the logical 

 wav to handle green lumber before an attempt 



WOOD STEAMING AND KILN-DRYING SYSTE.M AS EMPLOYED BY JOHN SCIIROEDER LUMBER COMPANY AT MILWAUKEE, WIS. 



2. THE STEAMING CYLINDER OPEN 3. DRY-KILN TRUCK OF MAPLE FLOOR- 



1. THE STEAMING CYLINDER CLOSED 



ING STOCK BEING WITHDRAWN FROM CYLINDER 



SECTION OF DRY-KILNS 



