558 



INDUSTRIAL USES OF WOOD. 



distinguished further as round logs, and balks which have 

 been squared, or are of rough prismatic shape and are then 

 termed sided timber. 



(a) Thus, timber in the round is the part of a stem which 

 has been merely barked, and may be used directly as piles, 

 masts and spars, wheel-hubs, scaffolding-poles, pillars, anvil- 

 stocks, telegraph-posts, hop-poles, or, when bored, for water- 

 pipes. 



(b) Balks are used as beams in the construction of houses, 

 bridges or ships, being logs squared roughly either with the 

 axe or saw. If not quite square they are termed waney 

 (Fig. 320, o, p, q, r, s, t, u, r), wanes being the natural surface 



Fig. 320. Log with bark, balks 

 without bark. 



Fig. 321. -Half -balk. 



of the timber, and panes the flat, hewn or sawn surfaces from 

 which side-pieces have been removed. In the case of waney 

 balks, for which rarely more than two-thirds of the trunk are 

 utilised, the waste is about 12 to 15 per cent, of the whole, 

 while, when the timber is square, the loss is about 27 per 

 cent. 



Boles about 60 feet long and of about 8 inches mid- 

 diameter, corresponding to 12 inches diameter chest-high 

 (4^ feet from the ground), are commonly used for balks. 



(c) Round oakwood is sometimes split through the centre 

 into half-balks, with a section as shown in Fig. 321. These 

 half-balks are met with in the Baltic oak-trade, and in the case 

 of oak from the Spessart, they are used in cabinet-making 

 and joiners' work. 



