On the Mutual Influence between Longitudinal and 

 Circular Magnetizations in Iron and Nickel. 



By 



K. Honda, RIGakushi, 

 Post-Graduate in Physics. 



With Plates XXIV & XXV. 



The change of mngnetization of iron and nickol wiroH duo 

 to electric cnrrent passing throngli them attracted tlie attention of 

 several physicists. Marianini'^ first o])served the decrease in the 

 moment of a permanent magnet by discharging a Leyden jar 

 tlirough it. The effect of longitudinal cnrrent on the intensity 

 of magnetization of an iron wire placed in constant magnetizing 

 field was examined by G. Wiedemann.-' He arrived at the 

 same result as Marianini, but he found further that when the 

 current is broken, the magnetization is considerably increased. 

 Villari'^ undertook similar experiments in connection with the 

 effect which bears his name, and obtained analogous results. He 

 concludes that longitudinal current increases the magnetization 

 of soft iron in weak magnetizing fields and decreases it in the strong, 

 and that on breaking the current, there is always increase of 



1) Ann. de ehem. et phys. 16, 436, 1846. 



2) Pogg. Ann. UT, 21.3, 1862. 



3) Pogg. Ann. 126, 103, 1865. 



