solar family. We see these sister planets of
our world circulating under the starry vault, like luminous points whose
brilliancy is sometimes dazzling. For us they are marvelous celestial
birds hovering in the ether, upheld by invisible wings. The Earth is
just the same. It is supported by nothing. Like the soap-bubble that
assumes a lovely iridescence in the rays of the Sun, or, better, like
the balloon rapidly cleaving the air, it is isolated from every kind of
support.

Some minds have difficulty in conceiving this isolation, because they
form a false notion of weight.

The astronomers of antiquity, who divined it, knew not how to prevent
the Earth from falling. They asked anxiously what the strong bands
capable of holding up this block of no inconsiderable weight could be.
At first they thought it floated on the waters like an island. Then they
postulated solid pillars, or even supposed it might turn on pivots
placed at the poles. But on what would all these imaginary supports have
rested? All these fanciful foundations of the Earth had to be given up,
and it was recognized as a globe, isolated in every part. This illusion
of the ancients, which still obtains for a great many citizens of our
globule, arises, as we said, from a false conception of weight.

Weight and attraction are one and the same force.

A body can only fall when it is attracted, drawn by a more important
body. Now, in whatever direction we may wander upon the globe, our feet
are always downward. _Down_ is therefore the _center_ of the Earth.

The terrestrial globe may be regarded as an immense ball of magnet, and
its attraction holds us at its surface. We weigh toward the center. We
may travel over this surface in all directions; our feet will always be
below, whatever the direction of our steps. For us, "below" is the
inside of our planet, and "above" is the immensity of the Heavens that
extend above our heads, right round the globe.

This once understood, where could the Earth fall to? The question is an
absurdity. "Below" being toward the center, it would have to fall out of
itself.

Let us then picture the Earth as a vast sphere, detached from all that
exists around it, in the infinity of the Heavens. A point diametrically
opposed to another is called its _antipodes_. New Zealand is
approximately the antipodes to France. Well, for the inhabitants of New
Zealand and of France the top is reciprocally opposed, and the bottom,
or the feet