STRUCTURAL MATERIAL 79 



woodwork (if it is so directed) cut so that 

 it may be fitted together with but little 

 trouble. It should be specified, however, 

 that it be well seasoned and not warped. 

 Warped millwork, especially sash bars and 

 glazing bars, are exceedingly difficult to put 

 in proper position. 



Some factories now build their eave plates 

 and sash bars on the concentric principle, 

 which does away with the necessity of cut- 

 ting the ends of sash bars differently for 

 roofs of different angles. 



