balls were then brought near the small
ones, and great care was taken to see if there were any twist in the
wire by which they were suspended. It was found that the wire had become
twisted on the approach of the large leaden balls, and thus he was able
to prove that every particle of the attracted and attracting body are
mutually concerned in the Attraction of Gravitation. There is abundant
evidence of the application of this force in relation to our earth, as
we shall see later on.

The universality of the Attraction of Gravitation is a fact that has
been proved in a thousand ways, and a thousand times. All stars and
suns, and all planets, satellites and comets and nebulae are subject to
this universal law. Astronomy teaches us that its power extends across
the vast abysses of space, and that stars situated at distances that
cannot possibly be measured, are subject to this world-wide law. Some of
the greatest discoveries in astronomical science were due to the
operations of this wonderful law, the gravitating influences of certain
planets indicating their existence, although their discovery had not yet
been made.

The discovery of Neptune through the mathematical calculations of Le
Verrier and Mr. Adams in 1846 was the crowning proof of the Law of
Gravitation. Mr. Adams in England had noticed that the planet Uranus was
being pulled out of the course by some unknown power, and so set to work
to calculate the position of the body which thus influenced the motion
of Uranus in its orbit. He located the position of the supposed
influencing body strictly by mathematical calculations, and then took
his results to the Astronomer Royal. Delay, however, occurred in the
search for the supposed new planet, and nothing was done further in the
matter for many months. Meanwhile Le Verrier in France, unknown to Mr.
Adams, had been making similar calculations with reference to the
perturbations of Uranus, and had arrived at similar results.

These results were sent to the Berlin astronomers, and the heavens were
searched for the supposed new planet. After a time, the planet was
discovered in that part of the heavens indicated by Le Verrier, and for
a time his name stood out as the sole discoverer. Gradually, however,
the claims of Adams were admitted and recognized, and to-day his claims
to participate in the honour of the wonderful achievement are generally
admitted. Thus the discovery of Neptune gave to the Law of Gravitation a
s