HACKIA 



Alternative Names. Lignum-vitae (12). Iron-tree. Iron- 

 wood. 



Sources of Supply. British Guiana, West Indies. 



Physical Characters, etc. Recorded dry-weight 51-59! lbs. 

 per cu. ft. Hardness Grade 3, compare Blackthorn or rather 

 harder. Smell when worked distinctly resembling Tuberose. 

 Taste insipid. Burns well with some crackling : embers glow 

 in still air : gives off a faint aroma : heat expels a brown juice. 

 Solution with water or alcohol light brown. 



Grain. Coarse and open. Surface lustrous. 



Bark ? There are peculiar oval impressions in the wood im- 

 mediately under the bark. 



Uses, etc. "Mill-cogs, shafts, furniture, walking-sticks" (78). 

 Almost unbreakable, splits readily and raggedly though straight. 

 Planes badly by machine as it contains much grit which is bad 

 for the cutting edge of tools. " A tree squaring 16-18 inches 

 free of sap-wood by 65 ft. long " (78). 



Colour. Uniform darkish to lightish brown in zones. Sap- 

 wood? 



Anatomical Characters. Transverse section : — 



Pores. Conspicuous from their size and colour, size 2, very 

 coarse, little variation except in the groups : very evenly dis- 

 tributed, though sometimes collected into zones : some single, 

 but many subdivided, radial groups of 1-4 or even 7 : groups 

 sometimes crowded, appearing compound and irregular : 

 much brown resin or gum : few 0-20 per mm. 



Rays. Just visible, size 5, fine, uniform : equidistant, rather 

 less than a large pore-width apart : very weak, running close 

 round the pores : much denser than the ground : many 4-7 per 

 mm. : light brown. 



Rings. Doubtful : a zone-like appearance here and there, 

 nothing definite. 



Soft-tissue. Abundant, partly surrounding the pore-groups 

 and sometimes connecting one or more : cells, size 7 (pore-scale), 

 light brown. 



Pith. ? 



Radial Section. Pores prominent though not conspicuous : 

 mostly empty : dully shining. Rays readily visible, incon- 

 spicuous, brown, crystalline flakes of the same colour as the 

 ground. Rings not traceable. Soft-tissue prominent as rather 

 fighter brown borders to the pores, giving the wood a hoary 

 appearance. 



Tangential Section. As the Radial, but the pores are more 

 prominent on account of the frequent occurrence of a milk- 

 white deposit. Rays very minute, brown lines about 1 mm. 

 high, of one row of broad cells. Soft-tissue much more pro- 



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