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VI. Experimental Researches in Electricity. — Seventh Series. By Michael Faraday, 

 D.C.L. F.R.S. Fullerian Prof . Chem. Royal Institution, CmT. Memb. Royal and 

 Imp. Acadd. of Sciences, Paris, Petershurgh, Florence, Copenhagen, Berlin, 8^c. 8^c. 



Received January 9, — Read January 23, February 6 and 13, 1834. 



§.11. On Electro-chemical Decomposition, continued, ^[iv. On some general 

 conditions of Electro-decomposition. ^ v. On a new Measurer of 

 Volta-electricity . ^ vi. On the primitive or secondary character of 

 bodies evolved in Electro-decomposition. ^ vii. On the definite nature 

 and extent of Electro-chemical Decompositions. §. 13. On the absolute 

 quantity of Electricity associated with the particles or atoms of Matter. 



Preliminary. 



66 1 . 1 HE theory which I believe to be a true expression of the facts of electro- 

 chemical decomposition, and which I have therefore detailed in a former series of 

 these Researches, is so much at variance with those previously advanced, that I find 

 the greatest difl&culty in stating results, as I think, correctly, whilst limited to the use 

 of terms which are current with a certain accepted meaning. Of this kind is the term 

 pole, with its prefixes of positive and negative, and the attached ideas of attraction 

 and repulsion. The general phraseology is that the positive pole attracts oxygen, 

 acids, &c., or more cautiously, that it determines their evolution upon the surface ; and 

 that the negative pole acts in an equal manner upon hydrogen, combustibles, metals, 

 and bases. According to my view, the determining force is not at the poles, but within 

 the decomposing body ; and the oxygen and acids are rendered at the negative ex- 

 tremity of that body, whilst hydrogen, metals, &c., are evolved at the positive ex- 

 tremity (518. 524.). 



662. To avoid, therefore, confusion and circumlocution, and for the sake of greater 

 precision of expression than I can otherwise obtain, I have deliberately considered the 

 subject with two friends, and with their assistance and concurrence in framing them, 

 I purpose henceforward using certain other terms, which I will now define. The poles, 

 as they are usually called, are only the doors or ways by which the electric current 

 passes into and out of the decomposing body (556.) ; and they of course, when in 

 contact with that body, are the limits of its extent in the direction of the current. 

 The term has been generally applied to the metal surfaces in contact with the decom- 

 posing substance ; but whether philosophers generally would also apply it to the 



