120 INDUSTRIAL USES OF WOOD. 



3,081,1^ 



WhcD sawing logs into raihvay-slecpevs, it is evident that the 

 waste shoukl he reduced to a minimum, and the following facts 

 should be noted : — 



Diameter of log 

 at small end. 



For 1 sleeper . . . . .10 inches 

 ,, 2 sleepers . . . . . 14 ,, 



.> 3 ,, 17 ,, 



„ 4 „ 19 „ 



Larger timber, especially of oak, is generally too valuable to be 

 converted into sleepers, and on the Continent usually only third- 

 class oak timber is thus used. There is between 30 and 40 per 

 cent, of waste. 



Up to a recent period oakwood was considered essential for 

 railway-sleepers, on account of its durability, extending to 10-16 

 years. Highly resinous narrow-zoned larch sleepers last 10 years, 

 and those of Scotch pinewood similarly characterised last 7-9 

 years, whilst other woods unless injected were formerly hardly 

 used at all. As, however, the supplies of oakwood in Europe are 

 quite insufficient for the supply of railway-sleepers, and the 

 price of good oak timber is very high, after sufficient experience 

 of the advantage of injecting timber, Scotch pine, spruce and 

 beech have been largely used. 



Sleepers injected with various 

 the following durability : — 



Oak . 



Scotch pine . 

 Spruce 



,, (in liavaria) 

 Beech 



Young oakwood, owing to its greater density, is more suitable 

 for raihvay-sleei)ers than old timber. Tlie fact that many oak 



