Brown — Meclmnicol Stress and Magnetisation of Ir 



185 



Experiments were now made to test the effect of varying the longitudinal 

 stress on tlie wire when it was placed in a uniform magnetic field throughout 

 its whole length. An annealed No. 16 iron wire was fixed in position inside 

 the solenoid, which was arranged to give a longitudinal magnetic field of 



> 



7^ 





-f- 



f 



i 



7 



=r' 



2-5 c.g.s. units. A cycle was taken wlien a known load was on the wire, 

 the maximum current through the wire being 2-06 amperes; the load on the 

 wire was then increased and a cycle again taken, and so on for eight different 

 values of the load, the longitudinal magnetic field round the wire being 2-5 



2h2 



