THE TIMBERS OF COMMERCE 



uniformly scattered : few 0-5 per sq. mm. : mostly single, occa- 

 sionally subdivided in groups of 2-8 : usually empty. 



Rays. Need lens, size 5-6 : uniform : equidistant, much less 

 than width of a large pore apart, not avoiding but inter- 

 rupted by the pores : numerous, 11-13 P er mm : denser than the 

 ground- tissue : appear red against the darker ground. 



Rings. Very doubtful : zones of darker wood here and there, 

 but no definite boundary. 



Soft-tissue. Abundant in concentric lines linking the pores, 

 visible to the naked eye, size 3 (ray-scale) of the colour of the 

 rays but lighter. 



Pith.? 



Radial Section. Very prominent, black, shining grooves. 

 Rays visible but inconspicuous, fine, hoary flakes. Rings not 

 traceable, but the dark vertical bands are frequent. Soft-tissue 

 appears as hoary continuations or tails to the pores, sometimes 

 traceable for an inch or more beyond the pore-grove. 



Tangential Section. As the Radial, but the rays are invisible 

 with lens, about 0*3 mm. high and very difficult to make out, 

 and the soft-tissue is in irregular hoary patches. 



Type specimens from commercial sources checked by the 

 specimen in the Museum No. i, Kew, and by Gamble's de- 

 scription. 



No. 66. KOWHAI. Sophora tetraptera. J. Mill. 

 PLATE V. FIG. 42. 



Natural Order. Leguminoseas. 



Sources of Supply. New Zealand. 



Physical Characters, etc. Recorded dry-weight 48! Ib. per cu. 

 ft. Hardness Grade 3, compare Blackthorn. Smell or taste 

 none. Burns well with much crackling and a faint, peculiar 

 aroma : embers glow in still air : no juice expelled by heat. Solu- 

 tion almost colourless : potash turns it faint golden-brown with 

 a copious golden ppt. 



Grain. Fine. Surface scarcely bright. 



Bark. Brown, hard, leathery, not fissured : about inch 

 thick : of one layer. The rays are continued through the bark 

 and are gathered into cone-shaped pencils of about 20 rays, like 

 those found in the bark of Duguetia quitarensis. No. 2. 



Uses, etc. "Very tough and hard cogs recommended as a 

 substitute for Lignum-vitae " (24). Works very well. 



Authority. Collinson (24). 



Colour. Heart-wood whitish or brownish-white, not sharply 

 but clearly defined from the slightly lighter sap-wood, which is 

 about i inches wide. 



76 



