15 



CUTTING AND SEASONING TIMBER. 



The best time in the year for cutting timber is at the period of least growth, 

 before the time of active growth commences again ; it seasons better then, as the 

 cells are not so full of sap, which induces fermentation and consequent decay in 

 the cut timber. 



Wood, when freshly cut, contains generally about 45 per cent, of water, and a 

 part of this is dried off in seasoning. 



Percentage in weight of water in round wood from young trees, at different 

 periods after cutting. 



Kinds of Wood 6 mo. 1 year. 18 mo. 2 years. 



Beech 30.44 23.46 18.60 19.95 



Oak 32.7! 26.74 23.35 20.28 



Fir 33.78 16.87 15.21 1809 



Pine 41.49 18.67 15.63 17.42 



It appears from this table by F . B. Hough, that there is nothing gained in dry- 

 ness by keeping after eighteen months ; but English shipwrights prefer to keep 

 large timber for 3 years to season. 



If the carriage alone has to be considered, or even the use as fuel, it is evident 

 that it is very economical to attend to seasoning. 



Laslett states : "My experience of the approximate time required for seasoning 

 timber under cover, and protected from wind and weather, is as follows : — 



Pieces 24 ins. and upwards square, Oak, require about 20 mths. Fir 13 mths. 



Under 24 ins. to 20 ins. " " 22 « 11 « 



« 20 16 " " 18 " 9 « 



« 16 12 " " 14 " 7 " 



" 12 8 " " 10 " 5 " 



"8 4 „ " 6 " 3 " 



" Planks from one-half to two-thirds the above time, according to the thick- 

 ness. 



" If kept longer than the period named, the thin fine shakes which first open 

 upon the surface during the process of seasoning will open deeper and wider, until 

 they possibly render the logs unfit for conversion. If however the logs be re- 

 duced to the scantlings required after partial seasoning and then further allowed 

 to dry, they will not be liable to tear open so much, but by sinking gradually will 

 retain a more solid form, and be less objectionable to the eye when placed in 

 position." 



If possible freshly cut timber should be placed in running water, which partly 

 dissolves out the sap, and the timber then dries more readily and seasons more 

 effectually. It is therefore advantageous to float the wood in rafts, but if the 

 timber is left too long only partially submerged, there will be deterioration at 

 the line of flotation. Sea-water acts even better than fresh water ; and some- 

 times small timber is even put into tanks with salt water or lime water. Boards 

 require only about 7 days of such " curing." This process is especially valuable 

 when the wood is young and soft. 



In the process of seasoning, as the water dries out, the wood shrinks, and 

 cracks, the cracking taking place along planes radiating from the centre to the 

 bark. The younger wood contains more water than the old wood, and therefore 

 the cracks are wider at the circumference than in the heart wood. 



Newly felled timber should not be left on the ground, where instead of drying, 

 it will absorb moisture from the soil, but it should be raised some inches ofl' the 

 ground. 



The more slowly timber dries, the less it cracks, therefore the seasoning should 

 be done in the shade where there is no exposure to dr} T ing winds. If no other 

 shade is available, branches of trees should be strewed over the top. 



The cracking of timber at the ends may be prevented to some extent by pasting 

 heavy paper over the ends, or by painting with diluted muriatic acid neutralized 

 with lime. 



Hardwoods season more slowly and therefore crack less, than those of light 

 open grain. 



