with a large voltaic battery. 365 
Exp. 5. Platina and iron. The iron ignited instantly at 
the point of contact next the pole of the battery. Then the 
platina became ignited through its whole extent. After this 
the iron became more intensely heated than the platina, and 
the ignition of the latter decreased. 
Exp. 6. Platina and zinc. The platina was ignited ; the 
zinc was not ; but melted at the point of contact. In a sub- 
sequent experiment, the zinc did not melt ; but the platina 
ignited as before. 
Exp . 7. Zinc and iron. The iron was ignited : the zinc 
bore the heat without fusing. 
Exp. 8. Lead and platina. The lead fused at the point of 
contact. 
Exp. 9. Tin and platina. The tin fused at the point of 
contact. No ignition of either wire took place in the two last 
experiments. 
Exp. 10. Zinc and silver. The zinc was ignited before it 
melted : the silver was not ignited. 
The results in every case were the same to whichever pole 
of the battery either wire was presented. I varied these 
experiments by introducing several alternations of different 
wires continuously connected, into the circuit, and obtained 
in every instance analogous results. Thus 
Exp. 11. Alternations of platina and silver, three times 
repeated : all the platina wires were ignited, and none of the 
silver. 
Exp. 12. One zinc wire between two platina: both the 
platina wires were ignited, the zinc not. 
Exp. 13. One iron between two platina. Both the latter 
first ignited ; then the iron, which soon became most heated, 
atatd fused. 
