riginal with Aristotle; and
the classifications there outlined are at best but a vague foreshadowing
of the elaboration of the science. Such as it is, however, the natural
history stands to the credit of the Stagirite. He must be credited,
too, with a clear enunciation of one most important scientific
doctrine--namely, the doctrine of the spherical figure of the earth.
We have already seen that this theory originated with the Pythagorean
philosophers out in Italy. We have seen, too, that the doctrine had not
made its way in Attica in the time of Anaxagoras. But in the intervening
century it had gained wide currency, else so essentially conservative a
thinker as Aristotle would scarcely have accepted it. He did accept it,
however, and gave the doctrine clearest and most precise expression.
Here are his words:(2)

"As to the figure of the earth it must necessarily be spherical.... If
it were not so, the eclipses of the moon would not have such sections
as they have. For in the configurations in the course of a month the
deficient part takes all different shapes; it is straight, and concave,
and convex; but in eclipses it always has the line of divisions
convex; wherefore, since the moon is eclipsed in consequence of the
interposition of the earth, the periphery of the earth must be the cause
of this by having a spherical form. And again, from the appearance of
the stars it is clear, not only that the earth is round, but that its
size is not very large; for when we make a small removal to the south or
the north, the circle of the horizon becomes palpably different, so that
the stars overhead undergo a great change, and are not the same to those
that travel in the north and to the south. For some stars are seen in
Egypt or at Cyprus, but are not seen in the countries to the north of
these; and the stars that in the north are visible while they make
a complete circuit, there undergo a setting. So that from this it is
manifest, not only that the form of the earth is round, but also that it
is a part of a not very large sphere; for otherwise the difference
would not be so obvious to persons making so small a change of place.
Wherefore we may judge that those persons who connect the region in the
neighborhood of the pillars of Hercules with that towards India, and
who assert that in this way the sea is one, do not assert things very
improbable. They confirm this conjecture moreover by the elephants,
which are said to be of th