CATALOGUE OF THE TIMBERS OF THE WORLD 87 



Brazilian walnut. It was not sufficiently known to meet with a very 

 good reception, but after some little time the demand increased. 



The pores are very small and rather scanty, uniformly placed, and 

 generally plugged with a white substance. The medullary rays are 

 very fine and are joined at right angles with fine Hnes, presenting an 

 appearance as of a spider's web. 



Grapia-Punha. Apuleia precox. Mart. Brazil. 



This is a yeUowish-coloured wood, with a clean, free, straight grain, 

 moderately heavy, strong, and one of the most useful woods for planking 

 or timbering. It attains only medium dimensions, but may be turned to 

 account in many ways in the domestic arts. Brazilian Woods speaks 

 of this timber as being of first-rate quality for building and naval 

 architecture. 



Greenheart. Nectandra Rodioet, Hook. Weight, 66 lbs. 4 oz. British 

 and Dutch Guiana, the West Indies. 



The best quahty of greenheart is that from British Guiana and the 

 principal supply is from Demerara, whence it is received in hewn logs 

 nearly square, from 24 to 65 feet and even longer, and from 12 to 24 

 inches square, with waney edges. 



The logs are generally very straight in the grain, and remarkably 

 free from knots and defects. They contain a considerable thickness of 

 sap-wood, which, however, is not distinguishable from the heart-wood. 



It has been pointed out that on rare occasions the sap-wood is 

 ■attacked by a worm, which does not affect the heart- wood. The strength 

 of this wood exceeds that of most others, whether it be tried by the 

 transverse or tensile strain, or by a crushing force in the direction of the 

 fibres. Tried by the latter process it exhibits a pecuUarity unshared 

 probably by any other timber except sabicu. It bears the addition of 

 weight after weight without showing any signs of yielding ; and when 

 the crushing force is obtained, it gives way suddenly and completely 

 with a loud report, nothing being left of the pieces but a loose mass of 

 shapeless fibres. Very rarely it is liable, like sabicu, to a cross fracture 

 of the longitudinal fibres. Although not subject to side shakes, it is 

 somewhat liable to end splits, and great care has to be taken in sawing 

 it up. Immediately the saw has entered the wood, and the air is admitted, 

 the log may split with a loud report ; on one occasion this happened, and 

 the log flew upwards through the roof of the mill in which it was being 

 sawn. On this account it is desirable, as soon as the log has passed the 

 saw, to chain it round, securing the chain with strong dogs spiked into 

 the wood, which will hold it sufficiently, so that all that can occur wiU 

 be a severe split, without the risk of damage to the sawyers or saw frame. 



