of a view of certain Electrolytic Experiments. 203 



potash, or copper for instance, are subjected to electrolysis, it 

 is the base which is the direct subject of electrolyzation, the 

 liberation of acid and evolution of hydrogen being secondary 

 results. Objecting to this opinion, the distinguished author 

 of the letter alleges * there is nothing, I think, that I should 

 have anticipated less than that a solution of sulphate of 

 soda would be affected by the voltaic current precisely in 

 the same way as a solution of caustic soda, or that the 

 powerful affinities of the acid and the base should have no 

 influence upon the result." 



In reply to this objection, I beg leave to point out, that so 

 far is the direct influence of chemical affinity from being 

 hostile to electrolysis, that the more energetic the attraction 

 between the elements of an electrolyte, the more is it suscep- 

 tible of electro-chemical decomposition. According to Fara- 

 day, " from the period when electro-chemical decomposition 

 was first effected to the present time, it has been a remark 

 that those elements which in the ordinary phenomena of che- 

 mistry were most directly opposed to each other and combine 

 with the greatest attractive force, were those which were most 

 readily evolved at the opposite extremities of the decom- 

 posing bodies." (See Researches, page 198, paragraph 669.) 

 But if electrolysis be not impeded by the direct resistance of 

 the chemical affinity, is it consistent that it should be con- 

 trolled by an indirect resistance of the same force, such as is 

 exercised between the acid and the soda in the case under con- 

 sideration ? 



3. Professor Daniell, in support of the view of the subject 

 which he has taken, alleges, that " it will be easy for Dr. Hare 

 to convince himself by a few easy experiments that a solution 

 of sulphate of soda submitted to electrolysis becomes acid 

 in the zincode division of a diaphragm cell, not only by the 

 abstraction of sodium from it, but by the accumulation of acid 

 transferred from the platinode division ; just as he will find an 

 accumulation of soda in the latter arising from the secondary 

 action of the sodium transferred from the former." 



The ingenious author of these allegations has, however, 

 omitted to show that, supposing them to be true, they will be 

 more consistent with the idea, that the electrolyte which 

 undergoes decomposition is an oxysulphionide than an oxide. 

 Is it not clear that, according to either conception, there can 

 be no more, nor no less acid and alkali isolated, than one equi- 

 valent of each for every atom of oxygen evolved at the 

 anode ? 



4. Agreeably to the idea that oxysulphionide of sodium 

 is the subject of electrolysis, by a series of decompositions and 



