CHAPTER IV 



SELECTION, DURABILITY, SEASOKING, AND STORAGE OF WOODS 



Selection of wood. — The wood -worker must, of course, deter- 

 mine first what kind of wood is best suited for his purpose, and then 

 take steps to secure that the wood he obtains is a sufficiently good 

 sample of its kind. 



It cannot, unfortunately, be at all assumed that the botanical 

 determination of the species will prove a guarantee of the quahty 

 of a timber. Experience shows that Finns sylvestris or Quercus 

 Eobur from different parts of Europe, or even from different situa- 

 tions in one country, or Tectona grdndis from different districts of 

 India, may be a very different thing from the same species of Pine, 

 Oak, or Teak from elsewhere. Botanical identification, therefore, 

 though a most important preHminary, will not obviate other tests. 

 For many purposes, such as mere temporary hoardings, crates, 

 packing-boxes, or the carcases of low-priced furniture, cheapness 

 may be a consideration paramount to all others. 



Speaking generally, warm countries, sunny exposures, and dry, 

 •elevated land produce heavier, harder, and stronger timber. 



It is important that timber should be selected for felling when 

 mature, when the quantity of sapwood is small and the heartwood 

 nearly uniform, hard, compact, and durable. After this stage, 

 wood may become brittle, inelastic, discoloured, and perishable, 

 while before maturity, when the sapwood is in excess, it wffl seldom 

 be durable. Oak, for instance, for building, should not be less than 

 ^0 nor more than 200 years old, and Teak not less than 80 years 

 of age. 



Autumn or winter feUed wood, owing to the lower temperature, 

 sphts less in drying, and for this reason, and on account of the 

 season being less favourable to fungus-growth, is generally more 

 durable than that f eUed in the spring or summer. 



Shakes, knots, especially if disposed in a ring round a stick, 

 upsets, i.e., fibres crippled by compression, or cross-grain are all 

 defects which reduce the strength of timber. Both butt and top 

 should be close, solid, and sound, any sponginess near the pith, 



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