ed
round in a boat. Later on it was perceived to be necessary that the sun
should be able to travel beneath the earth, and so the earth was
supposed to be supported on pillars or on roots, or to be a dome-shaped
body floating in air--much like Dean Swift's island of Laputa. The
elephant and tortoise of the Hindu earth are, no doubt, emblematic or
typical, not literal.

[Illustration: FIG. 5.--Egyptian Symbol of the Universe.

The earth a figure with leaves, the heaven a figure with stars, the
principle of equilibrium and support, the boats of the rising and
setting sun.]

Aristotle, however, taught that the earth must be a sphere, and used all
the orthodox arguments of the present children's geography-books about
the way you see ships at sea, and about lunar eclipses.

To imagine a possible antipodes must, however, have been a tremendous
difficulty in the way of this conception of a sphere, and I scarcely
suppose that any one can at that time have contemplated the possibility
of such upside-down regions being inhabited. I find that intelligent
children invariably feel the greatest difficulty in realizing the
existence of inhabitants on the opposite side of the earth. Stupid
children, like stupid persons in general, will of course believe
anything they are told, and much good may the belief do them; but the
kind of difficulties felt by intelligent and thoughtful children are
most instructive, since it is quite certain that the early philosophers
must have encountered and overcome those very same difficulties by their
own genius.

[Illustration: FIG. 6.--Hindoo Earth.]

However, somehow or other the conception of a spherical earth was
gradually grasped, and the heavenly bodies were perceived all to revolve
round it: some moving regularly, as the stars, all fixed together into
one spherical shell or firmament; some moving irregularly and apparently
anomalously--these irregular bodies were therefore called planets [or
wanderers]. Seven of them were known, viz. Moon, Mercury, Venus, Sun,
Mars, Jupiter, Saturn, and there is little doubt that this number seven,
so suggested, is the origin of the seven days of the week.

The above order of the ancient planets is that of their supposed
distance from the earth. Not always, however, are they thus quoted
by the ancients: sometimes the sun is supposed nearer than Mercury
or Venus. It has always been known that the moon was the nearest of
the heavenl