TIMBER TESTING 301 



columns of different lengths were made with 

 specimens in which the ratio of length to mini- 

 mum lateral dimensions ranged between 2/1 

 and 36/1 at 12 per cent moisture. 



" Prom these tests the following data were 

 obtained : — 



1. Up to and including ratios of 12/1 the 



strength in end compression in all the 

 timbers was fairly constant, and the 

 specimens invariably failed in direct 

 compression. 



Under this condition the average 

 strength varied between 11,600 and 

 8,450 lbs. per square inch. The Modulus 

 of Elasticity in direct compression was 

 in all cases below that obtained in the 

 Cross Bending and Tensile Tests. 



Karri, as in other tests, shows the 

 greatest difference between the strength 

 ' green ' and ' dry,' the former being 46 

 per cent below the latter. The corres- 

 ponding figures for the other timbers 

 are : Yate 43 per cent, Blackbutt 40 per 

 cent, Tooart 35 per cent, Jarrah 31 per 

 cent. Red Gum 29 per cent, York Gum 

 and Wandoo 23 per cent, Morrell 22 per 

 cent and Salmon Gum 21 per cent. 



2. At a ratio of approximately 18/1, the 



