Electricity in Electrolytes. 101 



about alone, and after some time decompose another complete 

 molecule in the same manner, and so on ; and all these motions 

 and decompositions will take place just as irregularly as do the 

 motions of heat, to which they owe their origin. 



Further, with respect to the de])ortment of the complete mole- 

 cules towards one another, I am inclined to think that here, too, 

 it may sometimes happen that the positive partial molecule of 

 some complete molecule may assume towards the negative one 

 of some other a position more favourable than that enjoyed at 

 the moment by either of these two partial molecules with refer- 

 ence to the other partial molecule of its own complete molecule. 

 In such a case the two first partial molecules, which were before 

 estranged, will combine to form a complete molecule, and the 

 two others thereby set free — i. e. the negative constituent of the 

 first, and the positive of the second complete molecule — M'ill at 

 the same time either combine with each other, or, should the 

 motion of heat prevent their so doing, mix with the other com- 

 plete molecules, and there produce decompositions such as we 

 before described with reference to a single partial molecule. 



The frequency of such mutual decompositions in a given liquid 

 will depend, in the first place, upon the nature of that liquid, with 

 respect to the greater or less intimate connexion between the 

 constituents of the several complete molecules; and secondly, 

 upon the activity of the molecular motion, or, in other words, 

 upon the temperature. 



8. If now, upon a liquid whose molecules already move about 

 amongst each other in such a manner as to occasion an irregular 

 exchange amongst their partial molecules, an electric force acts 

 so as to cause a tendency in all positive partial molecules to 

 move in one direction, and in all negative ones to move in the 

 opposite direction, the difi'erence which must thereby be origi- 

 nated in the nature of the molecular motion is easily con- 

 ceivable. 



A free partial molecule will no longer follow altogether the 

 irregular and variable directions in which it was solicited by the 

 motions of heat, but it will change its course in obedience to the 

 acting force ; so that amongst the still very irregular directions 

 followed by the free, positive, partial molecules, some determinate 

 one will predominate, and at the same time the negative partial 

 molecules will, for the most part, move in a direction opposite to 

 the last. Further, in the action of a partial molecule upon a 

 complete one, as well as in the mutual action of two complete 

 molecules, all decompositions which at the same time permit the 

 partial molecules to move in obedience to the electric force will 

 be facilitated, and consequently will occur more frequently than 

 they could do in the absence of such a force ; for even in cases 



