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1908-9.] Low Temperature Experiments in Magnetism. 
men to warm to room temperature was to diminish its magnetic moment 
by 16 per cent. The magnet was now in a condition in which its magnetic 
moment at — 190° C. exceeded its magnetic moment at room temperature 
by about 15 per cent. 
The results for the steel wire in the quenched condition are exhibited 
in fig. 3. 
Results for Special Hard Steel. 
The results obtained on testing a specimen of this variety of steel are 
shown in figs. 4, 5, and 6. They resemble the results obtained for the steel 
Special Hard Steel (Forged) 
Fig. 4. 
wire. It will be seen that after the reversible state has been arrived at 
the magnitudes of the changes brought about by the cooling are much 
more marked in the case of the specimen when magnetised at —190° C. 
than when magnetised at room temperature. 
Results for Manganese Steel (6 per Cent. Mn). 
The results obtained for this steel in the annealed condition are shown 
in fig. 7, and are very remarkable. On magnetising the specimen at the 
temperature of the room its magnetic moment was found to be 250 C.G.S. 
units. On cooling the specimen to -190° C. its magnetic moment 
diminished to 93 C.G.S. units ; and on allowing it to warm to room 
temperature the magnetic moment fell to 59 C.G.S. units. From and 
