ox TUE MAGXETIZATIOX AXD RETEXTIVEXESS OF XICKEL. 313 



examine the residual magnetism of the nickel wire under the action 

 of two stresses, especially at the point where the susceptibility sud- 

 denly increases. The experiments were conducted in very much the 

 same wav as befijre. A nickel wire -40 cms. lono- and 1 nun. thick 

 Avas placed in a double solenoid, the second solenoid serving to neutral- 

 ize tlie earth's field. After the wire was demagnetized, magnetizing 

 forces of gradually increasing magnitudes were applied and removed. 

 The residual magnetism was then measured. All the applications and 

 removal of the magnetizing force were conducted very gradually and 

 readings were taken at each step. 



The wire was treated exactly as before as regards both the longi- 

 tudinal and the torsional stresses. The observations for each of the 

 combinations of longitudinal and torsional stresses are given in the 

 following tables, which also contain the ratios of the temporary and 

 residual magnetisms. 



I. W = 2.5kgs. cm-. 



T:=0 7-=U..j° per cm. 



10 •■ 

 .o Ciii. 



