ply repels each indiscriminately. But consider a little further;
the argon atom not only repels all advance on the part of oxygen and
nitrogen, but it equally holds itself aloof from its own particular
kindred atoms. The oxygen or nitrogen atom never rests until it has
sought out a fellow, but the argon atom declines all fellowship. When
the chemist has played his tricks upon it, it finds itself crowded
together with other atoms of the same kind; but lift up the little
test-tube and these scurry off from one another in every direction, each
losing its fellows forever as quickly as possible.

As one ponders this one is almost disposed to suggest that the atom of
argon (or of krypton, helium, neon, or zenon, for the same thing applies
to each and all of these) seems the most perfect thing known to us in
the world, for it needs no companionship, it is self-sufficing. There
is something sublime about this magnificient isolation, this splendid
self-reliance, this undaunted and undauntable self-sufficiency--these
are traits which the world is wont to ascribe to beings more than
mortal. But let us pause lest we push too far into the old, discredited
territory of metaphysics.

PROFESSOR J. J. THOMPSON AND THE NATURE OP ELECTRICITY

Many fascinating questions suggest themselves in connection with these
strange, new elements--new, of course, only in the sense of human
knowledge--which all these centuries have been about us, yet which have
managed until now to keep themselves as invisible and as intangible as
spirits. Have these celibate atoms remained thus always isolated, taking
no part in world-building? Are they destined throughout the sweep of
time to keep up this celibate existence? And why do these elements alone
refuse all fellowship, while the atoms of all the other seventy-odd
known elements seek out mates under proper conditions with unvarying
avidity?

It is perhaps not possible fully to answer these questions as yet, but
recent studies in somewhat divergent fields give us suggestive clews to
some of them. I refer in particular to the studies in reference to the
passage of electricity through liquids and gases and to the observations
on radioactivity. The most conspicuous worker in the field of
electricity is Professor J. J. Thompson, who for many years has had
charge of the Cavendish laboratory at Cambridge. In briefly reviewing
certain phases of his work we shall find ourselves brought into contact
with some of