64 



TASMANIAN TJMHKHS. 



In the dry woods the elasticity was unimpaired to | of 

 breaking strain; in the green ones to about a half. 



The nature of the fracture in each case will be seen from 

 the illustrations. Tasmanian trees are very large, and may 

 be got quite free from knots and with the grain evenly hard, 

 so that the above may be taken as ultimate breaking-weights 

 of well-selected timber free from shakes and defects. 



The results obtained for Deal could not be got in ordinary 

 work, except with small scantlings, chiefly owing to the 

 presence of knots; also, from the trees being small, the 

 hard grain may be at many angles in a single plank. From 

 these causes the timber does not give evenly throughout, and 

 a large plank will not carry so much weight in proportion 

 to its size as a small one will, in which these causes of failure 

 have been eliminated. 



TASMANIAN AND OTHER TIMBERS. 



(A. 0. Green.) 

 Arranged in order of stiffness from the deflections of specimens 

 one inch square, supported at ends, span two feet and load 

 one hundred pounds in centre of span. 



Name. 



Swamp Gum dry 



Stringy Bark „ 



Leatherwood „ 



Stringy Bark fresh cut 



Blue Gum dry 



Oregon Pine „ 



Yellow Deal —annual rings vertical* ,, 

 Yellow Deal — annual rings horizon- 

 tal* di-y 



Blue Gum fresh cut 



Myrtle or Beech dry 



Ash, English „ 



Celery Top Pine ...... ,, 



Oak, English ,, 



Beech, English „ 



King William Pine „ 



W = 100 lbs. 



Deflection 



inches. 



100 

 115 

 150 

 153 

 170 

 180 

 188 



195 



195 



210 



211t 



238 



243t 



257t 



655 



Breaking 



load. 



lbs. 



555i 



61 OA 



543 



341 



560i 



379 



353 



304f 

 326i 

 491 i 



387f 



182 



Deflections 



at 

 breaking. 



1 







5 



1 



1 



25 







1 

 2 

 4 



1-1 



1-655 



* Cut side by side from one Deal. 



t Calculated from the value of E given in Molesworths' Engineering 

 Pocket Book. 



