THE CONVERSION AND PRESERVATION 

 OF TIMBER 



To obtain the best results, all kinds of timber should be converted 

 immediately the tree is felled, or as soon afterwards as the circumstances 

 permit. By leaving the tree lying on the ground it will not automatically 

 become seasoned, or indeed be any better fitted for use. If the bark 

 remains on the tree, the latter as it cracks at the ends is liable to be 

 stained by the bark, which by degrees falls off and exposes the bare wood 

 to sun and wind and all variations of the weather. Insects attack it 

 from all points, laying their eggs in the bark and in the sphts and cracks 

 which develop on the ends and sides ; when these occur they will not 

 close again, and will seriously impair the value of the wood. Fimgus 

 also naturally develops, the result being that the tree becomes only a 

 large piece of decaying vegetation. The loss which ultimately occurs 

 in conversion is greatly increased, and the damage done by the insects 

 and fungi results in harm which may be discovered early or perhaps be 

 unsuspected till years afterwards, when the converted product has been 

 used in its ultimate position. 



The trunk should, therefore, be sawn at once into the logs, planks, 

 boards, and scantlings which wiU eventually be required, or if the exact 

 size be unknown, then to the nearest likely dimensions. In the past it 

 has been customary in some cases for engineers and architects to specify 

 that the timber shall have been felled for at least five years, or for some 

 less period named. Such a requirement is mistaken, and is not likely 

 to yield the desired result. 



It is necessajy to have a clear idea as to the meaning of the term 

 " seasoned," as applied on the one hand to a piece of wood small in 

 thickness, and on the other to a log or beam. The small piece when 

 seasoned is more or less dry from the outside to the core ; whereas the 

 wood of the " seasoned " log is by no means necessarily so. This latter 

 fact is rendered comprehensible by a consideration of the sequence of 

 events during the seasoning of a log. While this lies exposed to sufficiently 

 dry air, it loses water by evaporation, which takes place over the whole 



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