JOURNAL OF THE COLLEGE OF SCIENCE, IMPERIAL UNIVERSITY, 

 TOKYO, JAPAN. 



VOL. XVI, ARTICLE 8. 



Experiments on the Magnetostriction of Steel, 

 Nickel, Cobalt, and Nickel Steels. 



By 



H. NAGAOKA, Professor of Physics, 



and 



K. HONDA, Lecturer of Physics. 



With Plates I— II. 



§ 1. Introduction. 



§ 2. Magnetization of steel, nickel, cobalt, and nickel steels. 



§ 3. Apparatus for measuring change of length by magnetization. 



§ 4. Change of length by magnetization in 



(a) Steel ovoid, 



(b) Nickel ovoid, 



(c) Cobalt (cast and annealed) ovoids, 



(d) Keversible nickel steel ovoids containing 46%, S6%, 29^, 

 25% of nickel, 



(e) Eeversible nickel steel wires containing 45%, 35% of nickel in 

 low fields. 



§ 5. Effect of longitudinal stress on tlie magnetization of cobalt and nickel 

 steels and the relations reciprocal with the change of length. 



§ 0. Change of volume by magnetization in steel, nickel, cobalt, and nickel 

 steel ovoids. 



