92 



THE TIMBERS OF THE WORLD 



it to jarrah for girders, beams, and decking, in both strength and wear. 

 He says he constructed 500 feet of wharf nine years ago, and used it in 

 preference to jarrah and karri for cross-heads, girders, waUngs, sheet 

 piles, and decking (quoted by K. C. Richardson in a report on Tasmanian 

 Timbers).. An immense quantity was used in the construction of the 

 Admiralty Harbour Extension Works at Keyham in piles (fender piles 

 and rubbing pieces). It has been used very extensively in England for 

 railway waggon building, where it has given satisfaction. It has also been 

 tried for sleepers, but does not seem generally to find favour for this 

 purpose. The chairs make an almost clean cut through, which is probably 

 due to the hardness and want of elasticity in the wood. The weight of 

 the train passing over the chair compresses the softwood sleeper, which 

 rebounds when the weight is removed, while the blue gum is too hard 

 to compress and therefore crushes. Used as fencing it stands well, and 

 after many years does not seem to decay, even without any protection 

 of creosote or tar. It has been used extensively by the Post Office for 

 telegraph and telephone arms, with satisfactory results, and the Comp- 

 troller, Mr. G. Morgan, pro\4des a table of results of experiments made 

 with various Austrahan and Tasmanian timbers for this purpose : 



Size of Samples selected for Experiment 54 inches x 5^ inches x 4 inches 



Name of Timber. 



N.S.W. Ironbark 



Spero (Spotted Gum : Eucalyptus 

 maculata) ...... 



Tallow Wood 



Blackbutt 



White Box 



Forest ^lahogany . . . . ' . 



Turpentine 



Blue Gum 



Jarrah . . - 



Karri 



British Oak 1 



Breaking Load 

 in lbs. 



Weight in lbs. 



24.750 



24,000 

 22,000 



19,570 

 19.500 

 19,200 

 16,200 

 20,100 

 14.125 

 11,600 



74 



54 

 64 



57 

 73 

 59 

 62 

 69 

 67 

 59 

 54 



Specific Gravity. 



119 



•87 

 I 025 



•915 

 117 

 •946 

 •997 

 III 

 I 075 



■95 

 •87 



1 In English Oak, " K " = 16,800 to 21,000. 



It is satisfactory for platforms and deckings for wharves, and makes 

 good hard-wearing flooring, although perhaps Hable to become somewhat 

 sUppery. Blue gum, stringy-bark, and teak are all remarkable for their" 

 fire-resisting quaUties : it is difficult to say which is the best in this 

 respect. In September 1903, a disastrous fire occurred in the West 

 India Docks, and sheds containing all manner of soft and hard woods 

 were destroyed, some sleepers of blue gum and stringy-bark being the 

 only timbers which remained ; these showed very little sign of the heat 

 and fire, and were only shghtly charred at the edges. 



