exerted along
the straight lines joining the attracting bodies, that the intensity of
the attracting body is inversely as the square of the distance, while
the total force is proportionate to the product of their masses.

From the phenomena of light, heat, and electricity, we learn that the
centrifugal force due to aetherial pressure is exerted along straight
lines, that the intensity is inversely as the square of the distance,
while the total force between two bodies is equal to the product of the
quantities of electricity, which are regulated by the product of their
masses.

Thus, if every planet and satellite could be conceived to be motionless
in space, and these two forces could be set in operation without
producing rotation or translation in space, which is impossible, then
every planet and satellite would occupy, by the joint exercise of these
two forces, the same position in relation to the sun represented by
their mean distances, as long as the solar system existed as a separate
system in the realm of aetherial space. We have therefore discovered by
strict philosophical reasoning, based on Newton's Rules of Philosophy, a
real tangible centrifugal force existing throughout the universe;
because it is entirely due to the pressure of an universal Aether, whose
operation is ever directed from a central body, which force was
indicated by Herschel, and its existence to his mind was demonstrated by
the repulsion exhibited in connection with the tails of comets.

We have now to go a step further, and show that the same pressure also
includes the magnetic phenomena, as indicated by Clerk Maxwell, and that
magnetic phenomena are also due to the aetherial medium, and then we
shall have linked together in one common medium the majority of the
forms of energy, as light, heat, electricity and magnetism, with which
we are familiar.

If it be demonstrated that these two forces, the centrifugal force and
the centripetal force, can conjointly account for all the motions of the
celestial bodies, then we shall have conclusive evidence that one of the
forces is physical and due to the pressure of a physical medium. After
that it will be comparatively easy to show that the centripetal force is
also due to the same aetherial medium, and then we shall have
accomplished that which we set out to accomplish, viz. the establishment
of a physical cause for universal Gravitation, which physical cause is
alone to be found in the pressur