130 



INDUSTRIAL USES OF WOOD. 



fts in fig. 36. The beams used for supporting llic deck are much 

 leas curved. 



Wood is now artificially bent for shii)building, as in ccr- 



FiG. 34. 



Fig. 3i 



[8S 



Fig. 36. 



/^ 



tain factories in Hungary, but it is then probably weaker 



than naturally curved wood. 



Kneed timber is formed where a bough 

 parts from the parent stem as in fig. 37. 

 The branch should accord in its dimen- 

 sions with the stem, and not be too 

 small when compared with the latter. 



The chief use of knee-pieces is in the 

 construction of river-barges ; wood of 

 smaller size is then required than for 

 ship-building, and in that case the 

 arnirt, fig. 37, is much longer than b, 

 whilst for ships it is only twice as 

 long. In North Germany, where oak 

 is scarce, large, branchy Scotch pines 



arc used for knees, which would otherwise be fit only for 



