ELECTRICAL PROPERTIES OF HYDROGENISED PALLADIUM. 



181 



The thermoelectric power of the palladium and hydrogenium couple, as 

 shown by this first experiment, was so large as to suggest investigating the 

 properties of the hydrogenium by coupling it with some other metal, such as 

 platinum or copper. The use of the palladium itself is besides open to the 

 possible objection that the passage of a current between it and hydrogenium 

 may cause a transfer of hydrogen. There was, however, no positive evidence 

 of such a possibility. 



In the next experiments to be described a triple junction was formed of 

 platinum, palladium, and hydrogenium. Rapidly alternating readings were 

 taken of the platinum-palladium and platinum-hydrogenium electromotive 

 forces, which were estimated in C.G.S. units. In this way the hydrogenium 

 and palladium were directly compared. The following are the results of one of 

 the experiments, the same wire being used as in the experiment already 

 described. By the addition of a little more hydrogen the resistance was raised 

 to 1-012 ohms. 



Comparison of Electromotive Forces of Palladium (P£-Pd) and Platinum- 

 Hydrogenium (Pt-Hd) at different Temperatures. 



The numbers are given in 10~ 4 of the C.G.S. units. 



Heating. 



Vt-¥d. 



7t-B.d. 



+ -19 



- -56 



2-06 



- 3-36 



5-57 



- 6-82 



9-51 



- 10-86 



11-9 



-10-7 



12 



- 9-33 



18-5 



- 7-4 



23 



+ -9 



27-5 



+ 8-26 



50 



31-3 



62-1 



41-3 



66-7 



47-2 



81-6 



61-7 



86-1 



67-9 



98-5 



77 



103-9 



82 



114-7 



95-2 



122-5 



102-3 



¥t-~Bd. 



Cooling. 



Ft-Rd. 



122-5 



102-3 



120-1 



98-5 



117-6 



94-8 



108-1 



90-3 



99-4 



84-5 



93-7 



79-6 



89 



74-2 



75-6 



62-5 



60-7 



48-6 



57-6 



46 



54-5 



43-7 



41-8 



32-7 



37-2 



29-8 



34-1 



27 



32-6 



25-4 



28-2 



21-5 



25-5 



20 



19-5 



14-9 



17-4 



13-5 



11-9 



9-3 



8-3 



6-1 



In this experiment the triple junction was enclosed in a small porcelain tube 

 and heated in a charcoal furnace. The temperature of 200° C. corresponds 

 approximately to the value 16 in Vt-Vd column, and temperature 300° C. to the 



