Brown — The Change of Length in Nickel Wires. 



47 



Table VIII. 



Rigidity = 715 x 10 6 grammes per sq. cm. 



The values of the contraction as affected by the rigidity, load, and 

 magnetic field in the three wires last mentioned, will be found to lie inter- 

 mediate to the values obtained with the wires when in the hardest and 

 softest states. 



In Table IX are collected the values of the rigidity and the values of the 

 contraction obtained with longitudinal magnetic fields of 200 units produced 

 by direct current and alternating current of frequency 150 per second, when 

 the wires were under the influence of two different loads. 



