THE CONVERSION OF THE ENERGY OF CARBON 



INTO ELECTRICAL ENERGY ON SOLUTION 



IN IRON. 



By PAUL R. HEYL. 

 (Read April 22, 1910.) 



In molten iron carbon dissolves with a liberation of energy,, 

 which, by providing a suitable negative electrode, may be obtained 

 in the form of an electric current. The resulting electromotive 

 force is quite small, but is clearly to be distinguished from the 

 accompanying thermo-electric efifect. 



The experiment about to be described was, in outline, to set 

 up a voltaic cell consisting of electrodes of wrought iron and 

 carbon immersed in a bath of molten iron or steel of a low carbon 

 content. Such an experiment is beyond the equipment of an 

 ordinary laboratory, and for its execution I am indebted to the 

 courtesy of Dr. Geo. W. Sargent, of the Carpenter Steel Company, 

 Reading, Pa., who placed the necessary facilities at my disposal. 



The ideal liquid for such a cell would be a carbonless iron, just 

 as fresh acid in an ordinary cell is more effective than one which 

 already contains some zinc in solution ; but the melting point of 

 such iron is too high to be reached in a steel furnace. It was, 

 therefore, necessary to employ a low carbon steel. On account of 

 its higher melting point wrought iron furnishes a convenient 

 material for the negative element. 



The positive element was built up of three carbon rods, such as 

 are used in arc lights, wired firmly to a copper rod at their upper 

 ends. Two such electrodes were prepared in case one should 

 crack in the melted metal. To minimize as much as possible the 

 danger of cracking, the carbon was gradually heated by placing 

 it at first near, and finally in, an empty red-hot crucible. In this 

 way the tips of the rod were made red hot. 



PROC. AMER. PHIL. SOC, XLIX, I94 D, PRINTED JUNE II, I9IO. 



49 



