If you take _anode_ and _cathode_, I would propose for the two elements resulting from _electrolysis_ the terms _anion_ and _cation_, which are neuter participles signifying _that which goes up_, and _that which goes down_; and for the two together you might use the term _ions_.... The word is not a substantive in Greek, but it may easily be so taken, and I am persuaded that the brevity and simplicity of the terms you will thus have will in a fortnight procure their universal acceptation. The _anion_ is that which goes to the _anode_, the _cation_ is that which goes to the _cathode_. The _th_ in the latter word arises from the aspirate in _hodos_ (way), and therefore is not to be introduced in cases where the second term has not an aspirate, as _ion_ has not. [Illustration: FIG. 12.] On May 15th Faraday replied as follows:-- [_Faraday to Whewell._] I have taken your advice and the names, and use _anode_, _cathode_, _anions_, _cations_ and _ions_; the last I shall have but little occasion for. I had some hot objections made to them here, and found myself very much in the condition of the man with his Son and Ass, who tried to please everybody; but when I held up the shield of your authority it was wonderful to observe how the tone of objection melted away. I am quite delighted with the facility of expression which the new terms give me, and shall ever be your debtor for the kind assistance you have given me. As though to prepare the way for a still further cutting of himself adrift from the slavery of using terms that might be found misleading, he added the following note:-- It will be well understood that I am giving no opinion respecting the nature of the electric current now, beyond what I have done on former occasions; and that though I speak of the current as proceeding from the parts which are positive to those which are negative, it is merely in accordance with the conventional, though in some degree tacit, agreement entered into by scientific men, that they may have a constant, certain, and definite means of referring to the direction of the forces of that current. The “former occasions” is a reference to an earlier suggestion that a _current_ might mean anything progressive, whether a flow in one direction or two fluids moving in opposite directions, or merely vibrations, or, still more generally, progressive forces. He had expressly said that what we call the electric current “may perhaps best be conceived of as _an axis of power having contrary forces, exactly equal in amount, in contrary directions_.” [Sidenote: ELECTRO-CHEMICAL LAWS.]