iSG 



H. XAOAUKA 



Tliu twisting apparatus is shown in tiir suljjuincd cut. 



It consisted ui' two liollow evJinders of '2.h cms radius. Tlic lower 

 cylinder was iixed to a tripod stand, while tlie upper one litted int(j it, 

 and Avas movable. The latter was graduated on its external cylindri- 

 cal surface at intervals of 20°, and by means of a pointer which was 

 cut on the corresponding surface of the fixed cylinder, tln' amount of 

 twist was easily read otf. The screw S attached to the lower 

 cylinder served to tix the upper one at any desired angle of twist. 

 On the inner surface of the movable cylinder, two vertical V grooves 

 were cut opposite each other. Un tliese tht' two ends of the thick 

 brass diamerral rod were made to slide. This i-od had a small hole 

 at its centre whi<h was just large I'liough to allow llie passage of the 

 brass wire attached to the lower end of the nickel wire. In order to 

 secure the axial position of this hole with reference to the twisting 



