The electron, its isolation and measurement and the determination of some of its properties — John Stuart Mill — John Shaqi
The electron, its isolation and measurement and the determination of some of its properties
John Stuart Mill · en
Now the most startling result of Faraday’s law is perhaps this, if we
accept the hypothesis that the elementary substances are composed of
atoms, we cannot avoid concluding that electricity also, positive as
well as negative, is divided into definite elementary portions which
behave like atoms of electricity.[7]
[Pg 23]
This looks like a very direct and unequivocal statement of the atomic
theory of electricity, and yet in the same lecture Helmholtz apparently
thinks of metallic conduction as something quite different from
electrolytic when he says:
All these facts show that electrolytic conduction is not at all limited
to solutions of acids or salts. It will, however, be rather a difficult
problem to find out how far the electrolytic conduction is extended,
and I am not yet prepared to give a positive answer.
The context shows that he thought of extending the idea of electrolytic
conduction to a great many insulators. But there is no indication that
he thought of extending it to metallic conductors and imagining these
electrical atoms as existing as discrete individual things on charged
metals or as traveling along a wire carrying an electrical current.
Nevertheless, the statement quoted above is one of the most unequivocal
which can be found anywhere up to about 1899 as to the atomic nature of
electricity.
The foregoing quotations are sufficient to show that the atomic theory
of electricity, like the atomic theory of matter, is not at all new
so far as the conception alone is concerned. In both cases there were
individuals who held almost exactly the modern point of view. In both
cases, too, the chief new developments have consisted in the appearance
of new and exact experimental data which has silenced criticism and
compelled the abandonment of other points of view which up to about
1900 flourished along with, and even more vigorously than, the atomic
conception. Even in 1897 Lord Kelvin, with a full knowledge of all
the new work which was appearing on X-rays and cathode rays, could
seriously raise the question whether electricity might not be a
[Pg 24]
“continuous homogeneous liquid.” He does it in these words: