244 NEW CLASSES OF GALVANIC CONDUCTORS. 



at the expense of the ground : the second, the returning 

 into the ground all the excess; by which the positive would 

 arrive at a maximum of intensity, were there not a want of 

 insulation : and from this want of insulation results, as a 

 third effect, the momentary discharge of the two poles into 

 the ground. It may be conceived, that very irritable or- 

 gans, serving as a vehicle to this process, will experience that 

 kind of shock, which accompanies the prompt restitutions 

 of the electric equilibrium. If my object were at the pre- 

 sent moment to display a theory of the electric charge, I 

 certainly should not content myself with these germes of 

 ideas, which however appear to me fertile in their conse- 

 quences. It may be presumed too, that this kind of exci- 

 tation, in which the ground at large concurs, must require 

 a much greater degree of irritability, than those in which 

 the equilibrium is established immediately from one pole to 

 The author the other. Whether the impossibility of obtaining chemical 

 could ne\er decompositions by the intervention of flame depend on this 

 mkal decom- circumstance, I cannot say ; or even whether the impossibi- 

 positions in lity be absolute: all I know is, that I have never produced 

 ' IS wa y* an y suc ] 1 effect, notwithstanding the numerous combinations 



I have tried. 

 In this case too When the insulating power, which has been so perempto- 

 tho flame acts r j]y ascribed to flame, be considered, the following observa- 

 at a distance. . ... . . rr , , . 



tion will appear interesting. 1 o produce the contractions 



just mentioned, if is not necessary, that the uninsulated ex- 

 citing arc should immediately touch the flame, as it may be 

 held several inches above it. I have sometimes succeeded 

 in producing contractions, when it has been held a foot and 

 half above it, particularly when I have armed this extre- 

 mity of the arc with a metallic disc a few inches in diame- 

 ter, in order to bring it into more intimate contact with the 

 hot air issuing from the flame, and serving as a conductor 

 to the positive electricity. 

 The exciting I shall just mention here another observation, which I 

 arc retains its h, ave repeated several times, but the particulars of which I 

 ■etianda! ™ "* am far fl ". om having sufficiently studied. When the exciting- 

 arc, brought into communication with the ground, has pro- 

 duced a contraction, by being placed simultaneously in con- 

 tact with the flame and nerves, it will retain this property for 



about 



