68 



TIMBER. 



additional notes — continued. 



In the oaks, two groups can be readily distinguished by the manner in which the 

 pores are distributed in the summer wood. In the white oaks the pores are very 

 fine and numerous and crowded in the outer part of the summer wood, while in the 

 black or red oaks the pores are larger, few in number, and mostly isolated. The live 

 oaks, as far as structure is concerned, belong to the black oaks, but are much less 

 porous, and are exceedingly heavy and hard. 



Fig. 42."— Wood of red oak. (For white oak see fig. 38 I 



mmmm 



Fig. 43. — \\ ood of chestnut. 



Fig. 44. — Wood of hickory. 



