2 AßT. 10.— K. HONDA & S. SHIMIZÜ. 



In these experiments, the range of temperatures was very 

 limited, so that the remarkable effect of high temperatures was not 

 observed. In the present case, the experiments were pushed beyond 

 the critical temperature of iron ; in addition to this, the change of 

 length in liquid air was also examined. 



§ 1. APPARATUS. 



The apparatus for measuring the change of length by magnetiza- 

 tion at high and low temperatures was substantially the same as 

 that used for the study of the effect of tension on the magnetic 

 change of length.* Repeated experiments showed that this arrange- 

 ment gave very consistent results, but that it was rather preferable 

 to flatten the surface of the vertically suspended wire in contact 

 with the rotating cylinder. To diminish the effect of tension on 

 the magnetic change of length as well as the yielding at high tem- 

 peratures due to tension, thick rods about 1 cm in diameter and 

 21 cm in length were employed. In the experiments at high tem- 

 peratures, the suspended weight was generally 1 or 2 Kilograms ; 

 its effects were consequently almost insensible. To the upper end 

 of the ferromagnetic rod, a copper rod about 1 cm thick and 25 cm 

 long was jointed by means of a copper screw, and then brazed. The 

 lower end of the rod was likewise attached to a similar copper 

 rod about 20 cm long. The screwed part in each end of the ferro- 

 magnetic rod was 1.5 mm. This connected system hung vertically 

 from a stout support by means of a brass stand with three levelling 

 screws. The support on which the tripod stand rested, was provided 

 witli a brass plate with a hole-slot-plane,arrangement. The free end 

 of the bar was connected with a copper wire about 1.5 mm thick 



* K. Honda and S. Shimizu, Jour. Sc. Coll. XVI, Art. 9. 1902; Phil. Mac. 4, 33S, 1902. 



