i HAN JE OF I, I'M. 'I'll BY MA.GNETIZA1 [05 



instead "I Btretching it b) 

 a suspended weight. The 

 shaded portions of the 

 protruding holder were 

 made of brass, while the 

 unshaded part was made 

 of wood to lessen the 

 conduction of heat. Care 

 was specially taken to 

 stretch the copper wire 

 in the direction of the 

 axis of the rod. 



The magnetizing coil 

 with a Dewar's tube 

 inside it, was placed 

 co-axially with our rod. 

 The contraction or elon- 

 gation of the specimen 

 was measured by the 

 rotating cylinder in con- 

 tact with a vertical cop- 

 per wire. The tempera- 

 ture of liquid air was 

 assumed to be -186°C. 



§ 2. METHOD OF OBSERVATION. 



The experiments at low temperature were conducted in the 

 following manner. The change of length at tlie temperature of the 

 room was first determined and compared with the corresponding 

 result obtained by the heating arrangement. The comparison showed 



