62 ART. 6. K. HONDA AND S. SHIMIZü. 



ascending one. If, however, the temperature be again increased 

 to its former value, the path nearly coincides with the former one ; 

 the further increase of temperature diminishes the magnetization 

 in such a manner that the magnetization is not interrupted by 

 the cooling process. An instance is seen in Fig. 7 j. Hence in 

 irreversible nickel steels, the magnetization at ordinary tempera- 

 ture can have any value ivhatever within a given limits, if the 

 cooled specimens be heated to a suitable temperature. Becquerel 

 who first studied the magnetic properties of irreversible nickel 

 steels, found that in the alloy, there were two states of stable 

 equilibrium ; but according to our results, there are an infinite 

 number of such states, a fact which may possibly prove to be 

 important in the theory of molecular magnetism. 



Comparing the magnetization at different temperatures in 

 these nickel steels, we notice that the critical temperature in the 

 descending branch of the temperature-cycle generally becomes 

 less, as the percentages of nickel decreases. As the content of 

 nickel diminishes from 70.329^ to 26.64?^, the critical temperature 

 falls from several hundred degrees to the ordinary temperature. 

 It is then highly probable that 25 9^ nickel steel, which is feebly 

 magnetic both at ordinary and liquid air temperatures, would 

 become strongly magnetic, if the cooling should be pushed still 

 further. If it once become strongly magnetic by cooling, it may 

 preserve this property, after the alloy is heated to the ordinary 

 temperature. It will be interesting to investigate, whether other 

 non-magnetic alloys, which consist of a magnetic and a non-magnetic 

 metal, would display a similar phenomenon on being cooled to a 

 sufficiently low temperature. 



The fact that the two strongly magnetic metals form a non- 

 magnetic metal is then nothing more than the lowering of the 



