448 DR. FARADAY'S EXPERIMENTAL RESEARCHES IN ELECTRICITY. 



travel in any other direction than what will accord with its course, and therefore can 

 never tend to pass otherwise than from the anode and to the cathode. 



964; In such a circle as that delineated, therefore, all the known anions may be 

 grouped within, and all the cations without. If any number of them enter as ions 

 into the constitution of electrolytes, and, forming one circuit, are simultaneously 

 subject to one common current, the anions must move in accordance with each 

 other in one direction, and the cations in the other. Nay, more than that, equiva- 

 lent portions of these bodies must so advance in opposite directions ; for the advance 

 of every 32*5 parts of the zinc h must be accompanied by a motion in the opposite 

 direction of 8 parts of oxygen at d, of 36 parts of chlorine at g, of 126 pp,rts of iodine 

 at / ; and in the same direction by electro-chemical equivalents of hydrogen, lead, 

 copper and tin, at e, h, k, and m. 



965. If the present paper be accepted as a correct expression of facts, it will still 

 only prove a confirmation of certain general views put forth by Sir Humphry Davy in 

 his Bakerian Lecture for 1806='^, and revised and re-stated by him in another Ba- 

 kerian Lecture, on electrical and chemical changes, for the year 1826 -f-. His gene- 

 ral statement is, that " chemical and electrical attractions were produced by the same 

 cause, acting in one case on particles, in the other on masses, of matter ; and that the 

 same property, under different modifications, was the cause of all the phenomena exhi- 

 bited by different voltaic combinations J." This statement I believe to be true ; but 

 in admitting and supporting it, I must guard myself from being supposed to assent 

 to all that is associated with it in the two papers referred to, or as admitting the 

 experiments which are there quoted as decided proofs of the truth of the principle. 

 Had I thought them so, there would have been no occasion for this investigation. 

 It may be supposed by some that I ought to go through these papers, distinguishing 

 what I admit from what I reject, and giving good experimental or philosophical 

 reasons for the judgement in both cases. But then I should be equally bound to 

 review, for the same purpose, all that has been written both for and against the 

 Necessity of metallic contact, — for and against the origin of voltaic electricity in che- 

 mical action, — a duty which I may not undertake in the present paper ^. 



^ ii. On the Intensity necessary for Electrolyzation. 



966. It became requisite, for the comprehension of many of the conditions attend- 

 ing voltaic action, to determine positively, if possible, whether electrolytes could 



* Philosophical Transactions, 1807. f Ibid. 1826, p. 383. X Ibid. 1826, p. 389. 



§ I at one time intended to introduce here, in the form of a note, a table of reference to the papers of the 

 different philosophers who have referred the origin of the electricity in the voltaic pile to contact, or to chemi- 

 cal action, or to both ; but on the publication of the first volume of M. Becquerel's highly important and 

 valuable Traite de I'Electricite et du Magnetism, I thought it far better to refer to that work for these re- 

 ferences, and the views held by the authors quoted. See pages 86, 91, 104, 110, 112, 117, 118, 120, 151, 

 152, 224, 227, 228, 232, 233, 252, 255, 257, 258, 290, &c.— July 3rd, 1834. 



