346 On converting Heat Energy into Electrical Energy. [May 6, 



the diagram, of which the abscissae are proportional to the electro- 

 motive forces, the ordinates to the temperatures Fahrenheit. 



The highest electromotive force was 0*2607 volt at 197° F., the 

 highest degree to which the temperature was raised. 



If the platinum be replaced by a negative electrode of carbon, the 

 electromotive force will be higher. It may be of interest to mention 

 that the action of this element during heating is entirely different 

 from that of the galvanic battery during a similar elevation of its 

 temperature. 



