32 James Mann : 



Thirty-two shearinp^ tests were made, and the results show 

 that Avhen the phme of shear is parallel to the annual rings, all the 

 fracture's are fairly even, and in most cases, the same evenness 

 appears when the plane of shear is at right angles to the rings, 

 but in the case of Kokoilo and Jlimo, th*- fractures were very 

 angular, and increased the area of shear from 50 per cent, to 

 75 per cent. 



Table 5. 



Name of timber. - - Mean shearinj^ strength. 



Ulabo - - - - 2120 



Kokoilo - - - - 2010 



Madave - - - - 1810 



Alaga - - .. 1670 



Tamanau - - - - 1090 



Ilimo .... 882 



From the foregoing tables it will be seen that no definite 

 proportion exists between the stresses of the same timber, but 

 the timbers themselves vary a great deal in strength in their 

 relations to each other. Ulabo stands out prominently as the 

 stronger, the sum of the stresses being 4.3,877 pounds, Alaga 

 coming next with 30,460 pounds ; then Tamanau 25,742 

 pounds, Madave 19,555 pounds, KoJwilo 17,490 pounds, and 

 lUuio 14,468 pounds. From these figures it could b© reason- 

 ably expected that Ulabo would be a good engineering timber, 

 Alaga and Tamanau good w^oods for joinery and general w^ork, 

 and the remaining three — viz., Madave, Kol-oilo and Ilimo 

 — ought to be suitable for light joinery, cabinet work and fur- 

 niture. 



By referring to Table 1 it will also be noticed that the 

 strength does not follow in the order of the weights. 



Burning of Splinters. 



In addition to the mechanical tests, the colour and quality of 

 the ash produced from the burning of splinters was noted. 



When complete combustion takes place, as in the ordinary 

 fire stove or furnace, the ash is generally white or of a dirty 

 greyish colour, while an ordinary wooden match ahvays gives 

 a brittle black ash. If pieces of wood in the form of splinters 



