Change of Volume and of Length in Iron, Steel, 

 and Nickel Ovoids by Magnetization. 



By 



H. Nagaoka, Rigahiliakushi, 

 Professor of Applied Mathematics. 



AND 



K. Honda, Rigakushi, 

 Post-graduate in Physics. 



With Plates VI. & VII. 



1. In our former paper/^ we described some effects of 

 magnetization on the dimensions of nickel and iron, as well as 

 those of hydrostatic pressure and longitudinal pull on the mag- 

 netization. We then showed that there is a reciprocal relation 

 between the two, and that the Villari effect in iron is a natural 

 consequence of the observed changes of dimensions. Unfortunate- 

 ly on that occasion the range of the magnetizing field was 

 limited to a few hundred C.G.B. units, so that the investigation 

 of the behaviour of these metals in high fields was reserved for 

 further experiments. In addition to this, the ferromagnetics were 

 not of a shape to be uniformly magnetized with the exception 

 of the iron ovoids. It was therefore thought desirable to repeat 



]) Nagaoka and Honda, Journal of the College of Science, 9, 353, 1898; Phil. Mag. 

 46, 262, 1898. 



