8 ART. 9. — TT. XAGAOKA, AND S. KUSAKABE : EFFECT OF 



Tungsten steel behaves like ordinary steel, tlie only difference 

 being that the critical temperature is about 900°. 



Nickel. The susceptibility of nickel decreases with rise of 

 temperature ; which is more marked as we approach the transition 

 stage ; the magnetization soon reaches saturation, so that its 

 increase after ft = 100 is extremely small. The specimen was 

 nearly pure, and indicated evanescence of magnetization at about 

 500°. It must, however, be borne in mind that these temperatures 

 in all the ferromagnetics depend on the field strength as well as 

 on the history of the previous heating or cooling, as will be shown 

 later in the experiments in fields of constant strength. 



Cobalt. Of all the ferromagnetic substances which we ex- 

 amined, cobalt alone was characterized by several remakablc 

 changes by magnetization due to the raising of its temperature, 

 although most of the effects were equally participated in by other 

 ferromagnetics. 



The magnetization at ordinary temperatures is generally weak 

 in low fields, but gradually increases at a steady rate, so that 

 even in a field of 500 units, the magnetization can not be said to 

 be in a saturated condition. With increase of temperature, the 

 , Wendepunkt ' gradually recedes towards low fields, and the 

 magnetization on the whole increases in all fields. At about 500°, 

 the increase reaches its maximum, and is about twice as great as 

 at ordinary temperatures. Thus the effect of temperature is 

 singularly large in cobalt. With further increase of temperature, 

 the magnetization in low fields increases while that in high fields 

 decreases, and the nature of the change wrought by raising the 

 temperature of the metal resembles that in iron and nickel. The 

 curves of magnetization at high temperatures gradually become 

 less steep in high fields, while those at low temperatures show 



