Electric Theory of Matter
BY SIR OLIVER LODGE, F.R.S.
Page 3
to fill completely the space
occupied by a hydrogen or any other atom.
Inside a hydrogen atom electrons are therefore very
sparsely distributed, for there is manifestly plenty of
room for 800; more room indeed than there is, in the
solar system for the sun and planets; but some atoms
contain many more than this number, and the tightest
packing known exists in the atoms of the, radioactive
substances, Uranium, Radium, and the like, each atom of
which contains something like two hundred thousand
electrons. Even this is very far from tight packing, the
intervening spaces are still very great compared with
their size, but they are getting too crowded to be
comfortable, and nature does not seem to have evolved
any permanent atom more tightly packed than these.
Moreover even these are not quite stable and permanent,
every now and then a particle escapes and flies away,
from one or another atom, into space; so that if we take
a perceptible quantity of the substance---which of
course consists of many billion atoms---a considerable
number of particles are always being shot off from it;
hence a substance composed of these heavy atoms
maintains a continuous bombardment, emitting rays,
analogous to those Which Crookes had so strikingly
exhibited in 1879 in an exceptionally high vacuum tube.
The experimental discovery of spontaneous, radioactivity
is, due to M. Henri Becquerel in Paris in the year 1896,
one year after Roentgen's singular discovery of the
existence and electrical generation of X-rays.
Our present view of an atom of matter therefore is
something like the following: Picture to one's self an
individualized mass of positive electricity, diffused
uniformly over a space as big as an atom---say a sphere
of which two hundred million could lie edge to edge in
an inch, or such that a million million million million
could be crowded tightly together into an apothecary's
grain. Then imagine, disseminated throughout this small
spherical region, a number of minute specks of negative
electricity; all exactly alike, and all flying about
vigorously, each of them repelling every other, but all
attracted and kept in their orbits by the mass of
positive electricity in
