THE TIMBERS OF COMMERCE 



Grain. Fine, close and even. Surface somewhat shining, the 

 lustre being chiefly due to the ground tissue. 



Bark. Light grey with brown lenticels : thin : smooth when 

 young, cracking later with lattice-like fissures upon the 

 ridges of which a black skin persists. 



Uses, etc. Mathieu's opinion is that it " is one of the worst 

 woods that one can produce either for work or for fuel : does 

 not cut cleanly, decays rapidly, is scarcely good enough for 

 packing-cases. Twists and warps but little" (69). "Carving 

 and packing-cases " (131). 



Authorities. Hartig (42), pp. 33~44- Schwartz (106), p. 85. 

 Nordlinger (87), p. 510. Ditto (86), vol. iii. p. 45. Hough 

 49), part i. p. 47. Mathieu (69), p. 44. Wiesner (131), L. 12, 

 p. 970. 



Colour. Pure white : yellowish-white : reddish. A sap-wood 

 tree. 



Anatomical Characters. Transverse section : 



Pores. Require lens : extremely small, size 6 : uniform and 

 evenly distributed or rather fewer in the outer Autumn zone : 

 occasionally grouped in radial (not subdivided) lines of 2-7 

 pores : a tendency to branch : numerous, 100-125 P er sc l- mi n. 



Rays. Require lens : extremely fine, size 6 : lightly undu- 

 lating : often tapering : not very long : very slightly denser 

 than the ground-tissue : very numerous, about 17 per mm. : a 

 pore-width or less apart, only the fine ends avoiding the pores. 



Rings. Difficult to see in the solid wood, but very clear in a 

 thin section : boundary, a few rows of closely-packed pores 

 here and there adjoining a zone of Autumn wood poor in pores. 



Soft-tissue in the form of scattered cells only. 



Pith. 2-5 mm. thick : round edor 4-lobed : white : very soft. 



Radial Section. The pores require the lens and are then only 

 visible by means of their lustre : the rays are extremely fine 

 colourless lines about their own height apart and visible by re- 

 flection only in a certain light : the rings are just visible as 

 vague lines and the pith is greyish-brown and very prominent. 



Tangential Section. As transverse section, but the rays 

 appear as fine lines, about 25 mm. high, just perceptible with 

 lens? 



Type specimens taken from a tree which was known when in 

 leaf. 



No. 45. SNEEZEWOOD. Pteroxylon utile. 

 Eck. and Zey. 



PLATE IV. FIG. 33. 

 Natural Order. Sapindaceae. 

 Alternative Names. Nieshout : Umtati (12). 



52 



