36 PROPERTIES OF WOOD. 



27. Pad-auk (Pterocarpus). 



(P. indicus and P. macrocarpus from Burma, P. dalbergioides 

 from the Andaman Isles, also P. indicus from Cochin- 

 Chin a and New Caledonia.) 



In smooth longitudinal sections, bright lines of parenchyma 

 occur in the bright red ground tissue. The vessels are dis- 

 seminated scantily, and their sections are lustrous ; bright lines 

 of parenchyma concentric with the zones of wood. The colour 

 of the wood is usually bright red. The Andaman Padauk 

 appears to be the best (Gamble). 



28. Tulipivood, Canary Wliiteirood (Liriodendron) . 

 (From North America.) 



This wood is known also as American poplarwood, which 

 name is very misleading. 



Transverse Section. The medullary rays are very nume- 

 rous, distinct, bright lines resembling those in maplewood 

 (Fig. 17). The annual rings form distinct white lines; the 

 vessels are invisible. 



Radial Section. The medullary rays are narrow lustrous 

 bands ; they pass transversely through the annual rings, as 

 white lines. 



Tangential Section. With a suitable incidence of light the 

 white annual rings are visible. 



The sap wood is broad ; the heartwood, bright yellowish- 

 green or olive-coloured. 



29. Violet-wood or Myall (Acacia Iwmalophylla) . 



(South Australia.) 



On a transverse section, the vessels are seen equably distri- 

 buted, the bright bands of parenchyma are scarcely visible; 

 the general colour is brown to olive-green. Wood scented 

 like violets. [Acacia pendida, from Queensland and New South 

 Wales, is in England termed violet- wood.] 



(B) Coniferous Woods. 



There are no broad medullary rays nor vessels in coniferous 

 woods; the few vessels which surround the pith are of no 

 importance for identifying wood. The fine medullary rays 



