JOURNAL OF THE COLLEGE OF SCIENCE, IMPERIAL UNIVERSITY, 

 TOKYO, JAPAN. 



VOL. XIX., ARTICLE 9. 



Effect of Temperature on the Magnetization of Steels, 

 Nickel and Cobalt, measured magnetometrically. 



By 



H. Nagaoka, Rigakuhakushi. 

 Professor of Physics 



and 



S. Kusakabe, Eigakushi. 

 Postgraduate in Physics. 



( With lira •plates). 



§ 1. The importance of studying the effect of temperature on 

 the magnetization of ferromagnetic bodies has long been recognised 

 by physicists on account of its significant bearing on the molecular 

 theory of magnetism. As early as 1825, Kupffer investigated 

 the effect of heating upon the temporary magnetism of iron ; later 

 we find the names of Faraday, Wiedemann, Gaugain, Rowland, 

 Baue, Trowbridge, Tomlinson, and Ledeboer 1) in the list of 

 those who have investigated the effect of heating on magnetization. 



The numerous experiments on the magnetization of ferro- 

 magnetic substances at different temperatures were for the most 



1) Wiedemann's Elektricitat, III. 1896; Ewing. Magnetic Induction; du Bois, Art. 

 Propriétés magnétiques de la mature pondérable, Rapport* présentés au Congrès international 

 '/-■ Physique, Paris. 1900. 



