Most people have heard of the oriental race which puzzled over the
foundations of the universe, and decided that it must be supported on
the back of a giant elephant. But the elephant? They put it on the back
of a monstrous tortoise, and there they let the matter end. If every
animal in nature had been called upon, they would have been no nearer a
foundation. Most ancient peoples, indeed, made no effort to find a
foundation. The universe was a very compact little structure, mainly
composed of the earth and the great canopy over the earth which they
called the sky. They left it, as a whole, floating in nothing. And in
this the ancients were wiser than they knew. Things do not fall down
unless they are pulled down by that mysterious force which we call
gravitation. The earth, it is true, is pulled by the sun, and would fall
into it; but the earth escapes this fiery fate by circulating at great
speed round the sun. The stars pull each other; but it has already been
explained that they meet this by travelling rapidly in gigantic orbits.
Yet we do, in a new sense of the word, need foundations of the universe.
Our mind craves for some explanation of the matter out of which the
universe is made. For this explanation we turn to modern Physics and
Chemistry. Both these sciences study, under different aspects, matter
and energy; and between them they have put together a conception of the
fundamental nature of things which marks an epoch in the history of
human thought.
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