200 



BUCKTON TORSION MArHIXK. 



that the ends of the bar may be free to move endwise 

 these ends are gripped by two clutches or dogs, which 

 themselves rest against pins in the worm-wheel and the 

 beam respectively. 



The twisting moment is put upon the specimen by the 

 travelling weight W, the magnitude of this moment being 



FIG. 94 Buckton-Wicksteed Torsional Testing Machine. 



the product of this weight, and the distance it has moved 

 outwards from its position of equilibrium. The twist of 

 the bar is taken up, and the beam kept floating horizontally, 

 by means of the worm-wheel A, which is rotated by turning 

 the hand wheel H, this being keyed on to the shaft carrying 

 the worm which gears into the wheel. 



Professor Kennedy* states that this machine is capable 



*Min. Proc. Inst. C.E., Vol. Ixxxviii., p. 39. 



