432 
ARTICLE XV. 
On the Incandescence and Fusion of Metallic Wires by Eleciri- 
city. By Perer Riess*. 
[Extract from a paper read before the Academy of Sciences of Berlin, 
June 5, 1845.] 
THE extraordinary effects of electricity related by the ancients, 
as the type of which may be mentioned the melting of a sword 
in its uninjured scabbard, have led to a remarkable hypothesis 
concerning the melting by lightning or by electricity in general. 
Franklin, in the year 1747 Tf, assumed that electricity dissolved 
the cohesion of a metal without the aid of heat, and thus effected 
a cold fusion. When however it was discovered that a bell-wire 
melted by lightning singed the wood-work of a room, and Kin- 
nersley found that electricity artificially excited heated a piece 
of metal so much the more the smaller it was in section, that 
therefore lightning might produce heat sufficient to melt the 
point of a rapier without materially warming the other part of 
the blade, Franklin retracted his assumption t, and severely 
reproved himself for having grounded it upon a fact not suffi- 
ciently established. That great man evidently was not just to- 
wards the opinion which he had formed fifteen years previously ; 
-if the story of Seneca gave rise to the assumption and retention 
of his hypothesis, it certainly was not its chief support, but it 
was founded on the idea that igneous fusion differed from that 
effected by electricity. It is not therefore surprising that the 
idea of a cold fusion was again taken up forty years later by 
Berthollet §, who explained every action of electricity upon a 
substance as a forcible separation of its particles, and considered 
the heat which occurs on its melting, and which he, led into 
error by inaccurate experiments, rated at far too small a quan- 
tity, asa secondary phenomenon. 
The hypothesis of fusion brought about by a primary action 
of electricity has experienced the sad fate of being partly for- 
* Translated by Edmund Ronalds, Ph. D. 
+ Experiments and Observations. London, 1774, p. 52. 
t Ibid, p. 419. 
§ Chemische Statik. Berlin, 1811, vol.i. p, 270. 
