502 PROCEEDINGS OP THE AMERICAN ACADEMY. 



Figure 6 shows that the two points do not coincide, that on the 

 descending being about 12° lower than that on the ascending curve. 

 The diiFerence of form of the curves is noticeable, showing that the 

 regaining of magnetic properties on cooling is more gradual than their 

 loss on heating ; the sudden exaltation of magnetic properties occurs 

 at the same temperature in the first and second coolings. 



At the time of this writing the research has not been fully com- 

 pleted. We are, however, now engaged on further experiments, and 

 hope to present additional data in the near future. 



Rogers Laboratory of Physics, 

 June, 1894. 



