h the orbital motion
of the sun, we have now a physical conception for the first time of
Kepler's Laws, as well as a mathematical conception, that physical
conception being derived from the pressure and motions of the universal
Aether.

ART. 104. _Aether and Kepler's Third Law._--In Art. 28 we saw that
according to the Third Law of Kepler, the square of the periodic time
was proportionate to the cube of the mean distance of that planet from
its controlling centre. Newton proved that this Third Law was
mathematically correct, and that it could be mathematically accounted
for by the existence and operation of the universal Law of Gravitation.
As the centrifugal force is the exact opposite of that force in
intensity, proportion and mode of operation, it follows that
mathematically the centrifugal force also bears the same relation to the
Third Law that the centripetal force does.

We have, however, a physical basis for the centrifugal force, and it is
with the physical conception of this Third Law rather than with its
mathematical character that we are now dealing. Kepler by his Third Law
showed that the chief regulating factor in the orbital velocity of a
planet was its mean distance from the sun.

The great regulator of the velocity of any planet in its orbit is
simply planetary distance, and planetary distance alone. If there were
no other law which operated in the solar system than the centripetal
force, or the attractive force due to gravity, then such factors as mass
and density of a planet ought to play a most important part in the
orbital velocity of a planet, as the centripetal force directly
recognizes the influence of mass, that is, volume and density, but says
nothing about mean distances. This fact unmistakably points to the
existence, and demands the operation, of another force, which shall
explain, and that on a physical as well as a mathematical basis, how it
is that the mean distance of a planet from any centre regulates the
orbital velocity of that planet.

The only real and true conception of such a force is to be found in the
radiating waves and circulating motions of the aetherial medium, which
waves, like water waves, increase in their radial outflow and extent
with a regular decreasing intensity, and at the same time decrease in
their angular velocity as they recede from the sun. With such a regular
decrease of kinetic energy, there must necessarily be imparted to the
planets, as their mean di