( ^8 ) 



In the graphical representation all observed differences of potential 

 have been inserted ; the abscissae are strengths of the field, the 

 ordinates differences of potential, both in C. G. S. units. 



d. Transverse thermomagne- 

 tic difference of temperature 

 (rotation of isothermal lines). 

 This difference of tem- 

 perature might have been 

 observed after the same 

 method as the galvanomag- 

 netic difference of tempe- 

 rature; just as the latter 

 it arises graduallJ^ In con- 

 sequence of the heating of 

 the surroundings however 

 the temperature in the plate 

 was not so constant as in 

 the experiments without a 

 current of heat ; moreover it 

 was desirable, with a view 

 to the correction of the 

 thermomagnetic difference 

 of potential, to measure the 

 rotation under quite the 

 same circumstances as in 

 those experiments. Therefore the variation of temperature on the 

 reversal of the field was here determined for each of the thermo- 

 electric couples seperately. 



') The breadth of the phite was here 2,2 cM. 



