Galvanic Apparalus, Theory of Galvanism, &c. 293 



According to Singer, the electrical accumulation is as great 

 when water is used, as when more powerful menstrua are em- 

 ployed ; but the power of ignition is wanting, until these are re- 

 sorted to. De Luc showed, by his ingenious dissections of the 

 pile that electricity might be produced ioilhout, or with, che- 

 mical power. The rationale of these differences never has been 

 given, unless by mv theory, which supposes caloric to be present 

 in the one case, but not in the other. The electric column was 

 the fruit of De Luc's sagacious inquiries, and afforded a beautiful 

 and incontrovertible support to the objections he made to the 

 idea, tiiat the galvanic fluid is pure electricity, when extricated 

 by the voltaic pile in its usual form. It showed that a pile really 

 producing pure electricity, is devoid of the chemical power of 

 galvanism. 



We are informed by Sir H. Davy, that when charcoal points, 

 in connexion with the poles of the magnificent apparatus with 

 which lie operated, were first brought nearly into contact, and 

 then withdr;nvn four inches apart, there was a heated arch formed 

 between them, in which such non-conducting substances as quartz 

 were fused. I believe it impossible to fuse electrics by mechanical 

 electricity. If opposing its passage they may be broken, and if 

 conductors near them be ignited, they may he 'acted on by those 

 ignited conductors as if otherwise heated ; but I will venture to 

 predict, that the slightest glass fibre will not enter into fusion, 

 bv being placed in a cinrent from the largest machine or electri- 

 cal battery. 



I am induced to believe, that we must consider light, as well as 

 heat, an ingredient in the galvanic fluid ; and think it possible, 

 that, being necessary to vitality in animals, as well as vegetables, 

 the electric fluid may be the vehicle of its distribution. 



T will take this opportunity of stating, that the heat evolved 

 by one galvanic pair has been found by the experiments which 

 I instituted, to increase in quantity, but to diminish in intensity, 

 as the size of the surfaces may be enlarged. A pair containing 

 about fifty square feet of each metal, will not fuse platina, nor 

 deflagrate iron, however small may be the wire employed; for 

 the heat produced in metallic wires is not improved by a reduc- 

 tion ill their size beyond a certain point. Yet the metals above 

 mentioned are easily fused or deflagrated by smaller pairs, which 

 would have no perceptible influence on masses that might be 

 sensibly ignited by larger pairs. — These characteristics were fully 

 demonstrated, not only by my own apparatus, but by those con- 

 structed by Messrs. Wcthcrill and Peale, and which were larger, 

 but less capable of exciting intense ignition. Mr. Pealc's ap- 

 paratus contaiued nearly seventy square feet, Mr. VVetheriU's 



nearly 



