ulated with sulphuric
acid. He showed, by numerous experiments, that the decomposition
effected is invariably proportional to the amount of electricity
passing; that variations in the size of the electrodes, in the pressure,
or in the degree of dilution of the electrolyte, had nothing to do with
the result, and that therefore a voltameter could be employed to
determine the amount of electricity passing in a given circuit. He also
demonstrated that when a current is passed through different
electrolytes (compound substances decomposed by the passage of
electricity), the amount of the decompositions are chemically equivalent
to each other.

The extent of Faraday's work in the electro-chemical field may be judged
by considering some of the terms he proposed for its phenomena, most of
which, with some trifling exceptions, are still in use. It was he who
gave the name electrolysis to decomposition by the electric current; he
also proposed to call the wires, or conductors connected with the
battery, or other electric source, the electrodes, naming that one which
was connected with the positive terminal, the anode, and that one
connected with the negative terminal, the cathode. He called the
separate atoms or groups of atoms into which bodies undergoing
electrolysis are separated, the radicals, or ions, and named the
electro-positive ions, which appear at the cathode, the kathions, and
the electro-negative radicals which appear at the anode, the anions.

There were many other researches made by Faraday, such as his
experiments on disruptive electric discharges, his investigations on the
electric eel, his many researches on the phenomena both of frictional
electricity and of the voltaic pile, his investigations on the contact
and chemical theories of the voltaic pile, and those on chemical
decomposition by frictional electricity; these are but some of the mere
important of them. Those we have already discussed will, however, amply
suffice to show the value of his work. Rather than take up any others,
let us inquire what influence, if any, the various groups of discoveries
we have already discussed have exerted on the electric arts and sciences
in our present time. What practical results have attended these
discoveries? What actual, useful, commercial machines have been based on
them? What useful processes or industries have grown out of them?

And, first, as to actual commercial machines. These researches not only
led to the