THE THERMO-ELECTRIC EFFECTS OF LONGITUDINAL STRESS IN IRON. 33 



encloses a small area. The " on " branch of the curve shows a very 

 little fluctuation, hut, if anything can be seen from it, the manner of 

 variation is certainly of like nature to the corresponding branch of the 

 first process. 



The range of loading and unloading was then extended to 6 

 kilos. (Fig. 2). The " on " branch is more or less sinuous, and the 

 " off " branch runs towards a more negative region, having as before 

 a minimum near the close of unloading. By a cyclic change of load- 



