HAEDNESS AND COLOUKS OP WOODS 37 



this country. Grown only for ornament in Europe, in America 

 this tree is largely used for rafters, wainscots, roof-shingles, 

 boxes, furniture, and turnery, and increasing quantities now 

 arrive at Liverpool from New York under the names of American 

 or Yellow Poplar, American Whitewood or Canary Whitewood. 

 These names and that of '' TuUp-wood " are nearly all objectionable, 

 as previously applied to very different woods, or as suggesting a 

 connection between the tree, a member of the Magnolia family, 

 and the Poplars. The yellow variety of its wood comes from 

 moist low-lying ground, and is valued for staining or polishing, by 

 cabinet-makers, shop-fitters, and coach-builders. 



Exposure to air or Hght darkens the colour of most wood, as is 

 well seen in freshly felled, as compared to seasoned, Mahogany, 

 Moisture carries this darkening deeper into the wood, whilst the 

 black of Oak and the dark brown of Yew after prolonged immer- 

 sion in bogs are well known. The translucency of all sound 

 timber when in thin shoes gives it a characteristic lustre, whilst 

 incipient decay renders it duU and opaque. Any local departure 

 from the natural colour pecuhar to the species is an indication of 

 incipient decay. The deterioration that sets in directly gromng 

 timber passes maturity generally shows itself first by a white 

 colour at the centre of the butt-end of the leg. This is not a 

 serious defect ; but the yellowish-red tinge subsequently assumed 

 indicates a loss of toughness and tenacity, and suggests that the 

 log is not well fitted for constructive work. So too spots of 

 discoloration scattered through a log, especially at its butt-end, 

 are liable to prove centres from which serious decay, caused or 

 accompanied by parasitic fungal moulds, may spread. This 

 remark does not apply, however, to the so-called fith-fleck$ or 

 medullary spots, which are often numerous in woods when perfectly 

 soxmd. The reddish-brown tinge known as foxiness is a clear sign 

 of advanced decay, unfitting wood for any purposes requiring 

 strength ; but Oak is very often much prized by cabinet-makers 

 when in this condition, merely on account of its colour, it being 

 then known as " Brown Oak." 



Odours and resonance of woods.— The odours of woods, such 

 as the resinous smells of Deal or Teak, the fragrance of Cedars, 

 Toon, or Sandal-woods, the characteristic perfume of Camphor- 

 trees and the unpleasant smells of the Stinkwood {Ocot6a bulldta) 

 of South Africa and the Til {Oreoddfhni fdetens) of Madeira, may 

 sometimes be of use in discrimination, as, to an educated ear, 

 may the notes given out by different woods when struck by a 

 hammer. In the manufacture of musical instruments the wood 

 must be of uniform structure, even-grained, free from knots, well 



