434 OHM ON THE GALVANIC CIKCIIT. 



one-sided pressure on the various constituent parts would in 

 most cases act with unequal force, and sometimes even in con- 

 trary direction, and must thus excite a tendency in them to se- 

 parate from one another. From this consideration results a di- 

 stinct activity of the circuit, tending to produce a chemical change 

 in its parts, which I have termed its decomposing force, and I 

 have endeavoured to determine its magnitude for each particu- 

 lar case. This determination is independent of the mode, in 

 which the electricity may be conceived to be asssociated m ith 

 the atoms.* Granting, which seems to be most natural, that 

 the electricity is diffused proportionately to the mass over the 

 space which these bodies then occupy, a complete analysis will 

 show that the decomposing force of the circuit is in direct propor- 

 tion to the energy of the current, and, moreover, that it depends 

 on a coefficient, to be derived from the nature of the constituent 

 parts and their chemical equivalents. From the nature of this de- 

 composing force of the circuit, which is of equal energy at all places 

 of an homogeneous portion, it directly follows, that Avhen it is 

 capable of overcoming, under all circumstances, the reciprocal 

 connexion of the constituent parts, the separation and abduc- 

 tion of the constituents to both sides of the circuit are limited 

 solely by mechanical obstacles ; but if the connexion of the con- 

 stituent parts inter se, either immediately at the commencement 

 every where, or in the course of the action anywhere, overcome the 

 decomposing force of the circuit, then from that time no further 

 movement of the elements can take place. This general descrip- 

 tion of the decomposing force is in accordance with the experi- 

 ments of Davy and others. 



There is a peculiar state which seems to be produced in 

 most cases of the separation of the two elements of a chemically 

 compound liquid, which is especially worthy of attention, and 

 which is caused in the following manner. When the decomjjo- 

 sition is confined solely to a limited portion of the circuit, and 

 the constituent parts of the one kind are propelled towards the 

 one side of this part, and the constituent parts of the other 

 kind to its opposite side, then, for this very reason, a na- 

 tural limit is prescribed to the action; for the constituent 



* I shall shortly have occasion to speak of the peculiar import of this re- 

 ma\'k when I shall attempt to reduce the actions of the parts of a galvanic cir- 

 cuit on one another, as discovered by Ampere, to the usual electrical attrac- 

 tions and repulsions. 



