THE TIMBERS OF COMMERCE 



Pores. "Need lens, fine, 5-6, almost uniform : evenly distri- 

 buted throughout the whole width of the ring : very numerous, 

 200-400 per sq. mm. : in the solid wood they have the appearance 

 of clinging to the rays. 



Rays. Need lens, very fine, size 6, uniform : weak, running 

 round the pores : long, very slightly denser than the ground- tissue 

 and very difficult to see in the transparent section : numerous, 

 7-8 per mm. : more than a pore-width apart : white. 



Rings. Doubtful. An occasional zone poorer in pores but 

 not of necessity indicating the ring-boundary : little contrast 

 of colour : always narrow, i.e. slowly grown. 



Soft-tissue. None or only occasional wide-meshed cells. 



Pith. Round, to 2 mm. diam. Rarely perfect usually being 

 destroyed by cracks at the centre. 



Radial Section. Pores need lens, practically indistinguish- 

 able as are also the rays except when the wood is cleft. The 

 rings are quite indistinguishable. 



Tangential Section. As the Radial, but the rings are a trifle 

 clearer but still vague : the rays are fine lines about o - 2 mm . high. 



Type specimens from commercial sources checked by the 

 specimen in the Museum No. 1, Kew. I do not wish to 

 question the accuracy of its nomenclature, but the structure of this 

 wood is so unlike all the other species belonging to" the same 

 order which I have seen, that I think there may be an error 

 somewhere. Wiesner says it is Aspidosperma Vargasii, D.C., 

 but it totally disagrees with his description (p. 1000) of A. 

 Quebracho in material particulars. 



No. 149. TEAK. Tectona grandis. Linn. fil. 

 Plate XI. Fig. 94. 



Natural Order. Verbenaceae. 



Alternative Names. Indian Oak and many others in the Indian 

 dialects, see Gamble (37). 



Sources of Supply. Central and South India and Burmah 

 (37). North Borneo. 



Physical Characters, etc. Recorded dry-weight 34-55 lbs. per 

 cu. ft. Hardness Grade 6, compare Oak. Smell characteristic 

 and powerful, like old shoe-leather, very offensive when being 

 worked. Gamble says " it has a pleasant and strong aromatic 

 fragrance." Possibly it changes during drying. Burns well 

 with a long lively flame and much crackling : embers do not glow 

 in still air, but expire and leave the carbonized wood. Solution 

 with water or alcohol brown. 



Grain. Coarse and open, but much smooth wood in fast-grown 

 timber. Surface, greasy to the touch, dull. 



170 



