racter and
intensity, and in each case the pressure is due to the aetherial medium
which surrounds each atom or molecule.

When the atoms are equal in mass, then the resultant motion produced on
each atom would be exactly equal, but when the masses vary, the
resultant motion produced on each atom would vary also, though the
momentum in each case would be exactly equal and opposite, as momentum
is a compound term dependent partly upon the mass of the body concerned.

In Art. 16 we saw that when this third law was applied to planetary
phenomena, not only did the sun attract all the planets, but all the
planets attracted the sun with equal and opposite forces, and the
planets also attracted each other with equal and opposite forces. In the
same way it can be proved, that as the sun repels all the planets by the
pressure exerted by the aetherial centrifugal force on those planets,
the planets repel the sun with an exactly equal and opposite force at
their mean distances. In Newton's conception, however, of the third law
of motion, there was simply mathematical data to deal with, by which the
law was shown to apply to the planetary and stellar world. In the case,
however, of the centrifugal motion, we have a definite physical medium,
which by its motions produces the pressure on the planets or suns that
exist in space, which pressure forms the physical centrifugal force that
forms the counterpart of Gravitation Attraction.

Let us look at this phase of the case in detail, and by so doing help to
establish and confirm the physical existence of the force or motion
referred to. We have learned from Chapter IV. that as Aether is
gravitative, it surrounds all satellites and planets, suns and stars
that exist in the universe.

We have also learned from Art. 86 that Aether has an electro-magnetic
basis, as mathematically proved by Maxwell and experimentally proved by
Hertz. Thus we came to the conclusion that each satellite and planet,
sun and star, was an electrified body (Art. 81), or an electro-magnet
(Art. 88), possessing its own electric or electro-magnetic field.

We also learned that in every electro-magnetic field there was a
pressure which was ever directed away from the body that generated the
electro-magnetic waves. Now, as every satellite and planet, sun and
star, is a generator of these waves according to our theory, it follows
that every satellite and planet, sun and star, is the centre of a
centrifugal force, wh