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A. W. Davison 



metal M with respect to lead. It is apparent that this is a 

 straight line, and since the lead line is horizontal, we take it as the 

 reference line, and plot the thermo-electric powers of metals with 

 respect to the lead line. 



o 



a 



u 



TEMPERATURE 



Fio. 1 



/ / 





ti t2 



TEMPERATURE 



Fio. 2 



TEMPERATURE 



Fig. 3 



Thermo-electric diagram. In fig. 2, let CZ) be the standard lead 

 line, and ^5 be the thermo-electric power hne of metal M. 

 The constant 6 represents the distance Oy, while 2c is the tan- 



