PKOPERTIES OF WOOD. 



other broadleaved trees, but it is difficult to distinguish it from 

 conifers, except microscopically. On all the sections, a bright 

 line between the spring-wood and summer-wood is a good test 

 for horse-chestnut wood. 



Of foreign woods, only those will be described here that 

 come into the home-market and compete with indige- 

 nous wood. No foreign woods 

 either will be described that 

 have come into any of the 

 above-mentioned groups, as 

 they cannot be distinguished 

 with any certainty from 

 indigenous woods of the same 

 genus, either by ocular vision, 

 or microscopically. 



17. Species oj Hickory 

 (Hicoria (Carya)). 



(North American only.) 



Hickory-wood (Fig. 12) re- 

 sembles that of ash most 

 closely, but may be dis- 

 tinguished from ashwood by 

 the fine bright lines of paren- 

 chyma that run parallel to 

 the annual rings, and are 

 xM< ' ./ absent from ashwood. 



V V Sapwood broad, heartwood 



Fig. 20. Mahogany-wood (Swietenia), light brown. 



18. Mahogany-wood (Swietenia). 

 (Tropical America only.) 



Transverse Section. The medullary rays are distinct as 

 numerous, fine, bright lines. The vessels are uniformly dis- 

 tributed, partly filled with thyloses, and then sum as bright 

 dots, if not so filled, the dots are dark. Interruptions of 

 growth are marked by very distinct bright lines, resembling 

 annual rings ; the mass of the wood is slightly bright 



