138 On the Magnetization of Nickel. 



Twist. Magnetometer. 



518 



45 425 



90 380 



135 355 



180 323 



135 395 



90 465 



45 467 



475 



- 45 450 



- 90 370 



-135 320 



-180 360 



- 90 410 



- 45 490 



410 



This series shows that, with twisting in either direction in 

 this very strong field and with small load, the magnetization 

 of the wire diminishes instead of increasing. The curve^ if 

 traced, would resemble those given for iron by Sir William 

 Thomson (Phil. Trans. 1879, pp. 70-72). A comparison of 

 the various curves ot Mr. Nagaoka among themselves had led 

 us to suppose that this might be found to be the case. 



Lastly, following up the alteration in form shown in the 

 iron curves by Sir W. Thomson (loc. cit.) to be due to increase 

 of stretching-load, a few experiments were made on a piece of 

 the iron wire used by him with the view of finding whether 

 in a very weak field, or almost no field, and with a very 

 heavy pulling-load, the iron wire could be made to behave 

 like nickel, and to show magnetism increased by twist instead 

 of diminished. So far as we have gone, our experiments did 

 not show any likelihood of our being able to produce this 

 condition in the iron. The results obtained corresponded 

 very much in character with those observed by Sir W. Thom- 

 son. We do not, however, consider that our experiments, so 

 far as they have gone, are sufficient to settle this important 

 question. 



Glasgow, Dec. 1888. 



