58 



K. TSURUTA. 



Once more the wires were subjected to the same treatment, but 

 for a shorter time (about 7 hours). The third series of observations is 

 as follows : — 



In Fig. 2, PI. IV, the above are graphically expressed, the curves 

 being numbered in the order of the foregoing tables. 



Whence does this gradual shifting of the thermo-electric curve 



