THE TIMBERS OF COMMERCE 



tributed in radial, straggling, branched groups of as many as 76 

 pores in a group, rarely solitary or few in a group : numerous, 

 30-80 per sq. mm. : appear white in the solid wood : no green 

 but often red resin, which shines after being moistened : round 

 in shape. 



Rays readily visible with the lens : size 5-6, uniform and 

 equidistant : very slightly undulating : long : slightly denser 

 than the ground-tissue : numerous, 11-14 per mm. : the width 

 of a pore or less apart. 



Rings clear through a line of contrast, rather variable and not 

 always reliable. 



Soft-tissue. None. 



Pith. ? 



Radial Section. A little lighter in shade than the above sec- 

 tion. Pores readily visible as shallow, empty grooves: when 

 covered with blue-grey deposit they become conspicuous as 

 alternately converging and diverging, feathery bands. The rays 

 require the lens, and are about "05 mm. high. The rings are not 

 traceable, but the bands of pores running " cross-grained" are 

 very marked. 



Tangential Section. The rays are practically imperceptible 

 with the lens. 



Type specimens from commercial sources checked by those in 

 the Museum No. 1, Kew. 



No. 18. BAHAMA LIGNUM-VIT^. Guaiacum 

 sanctum. Linn. 

 Plate II. Fig. 14. 



Natural Order. ZygophyllaceEe. 



Synonyms. G. multijugum. Stokes. G. verticale. A. Rich. 



Sources of Supply. Bahamas, Southern United States, Florida. 



Alternative Names. Lignum Guaiaci (100), and also most of 

 those applied to G. officinale, from which it is seldom dis- 

 tinguished. 



Physical Characters, etc. Dry-weight 89 lbs.(ioo). Hardness 

 Grade 1, excessively hard, flinty. Smell and taste none. 

 Burns very well : embers glow in still air : exudes a reddish 

 resin when heated : the bark crackles like slate when thrown 

 upon the fire. Solution with water colourless : with alcohol 

 faint yellow. 



Grain. Fine, smooth, dense : spirally twisted. Surface cold 

 to the touch, bright. 



Bark. Rather rough with shallow fissures, about \ to \ inch 

 thick : excessively hard and brittle. Of three layers the outer- 

 most brownish-white, readily cracking off and exposing the 



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