[A] It will often happen that the electrodes used may be of such a nature as, with the fluid in which they are immersed, to produce an electric current, either according with or opposing that of the voltaic arrangement used, and in this way, or by direct chemical action, may sadly disturb the results.  Still, in the midst of all these confusing effects, the electric current, which actually passes in any direction through the body suffering decomposition, will produce its own definite electrolytic action.

833. viii.  A substance which, being used as the electrode, can combine with the ion evolved against it, is also, I believe, an ion, and combines, in such cases, in the quantity represented by its electro-chemical equivalent.  All the experiments I have made agree with this view; and it seems to me, at present, to result as a necessary consequence.  Whether, in the secondary actions that take place, where the ion acts, not upon the matter of the electrode, but on that which is around it in the liquid (744.), the same consequence follows, will require more extended investigation to determine.

834. ix.  Compound ions are not necessarily composed of electro-chemical equivalents of simple ions.  For instance, sulphuric acid, boracic acid, phosphoric acid, are ions, but not electrolytes, i.e. not composed of electro-chemical equivalents of simple ions.

835. x.  Electro-chemical equivalents are always consistent; i.e. the same number which represents the equivalent of a substance A when it is separating from a substance B, will also represent A when separating from a third substance C. Thus, 8 is the electro-chemical equivalent of oxygen, whether separating from hydrogen, or tin, or lead; and 103.5 is the electrochemical equivalent of lead, whether separating from oxygen, or chlorine, or iodine.

836. xi.  Electro-chemical equivalents coincide, and are the same, with ordinary chemical equivalents.

837.  By means of experiment and the preceding propositions, a knowledge of ions and their electro-chemical equivalents may be obtained in various ways.

838.  In the first place, they may be determined directly, as has been done with hydrogen, oxygen, lead, and tin, in the numerous experiments already quoted.

839.  In the next place, from propositions ii. and iii., may be deduced the knowledge of many other ions, and also their equivalents.  When chloride of lead was decomposed, platina being used for both electrodes (395.), there could remain no more doubt that chlorine was passing to the anode, although it combined with the platina there, than when the positive electrode, being of plumbago (794.), allowed its evolution in the free state; neither could there, in either case, remain any doubt that for every 103.5 parts of lead evolved at the cathode, 36 parts of chlorine were evolved at the anode,