e surface, and others by
their shells cleaving to the rocks! While the sea itself, approaching
to the land, sports so closely to its shores that those two elements
appear to be but one.

Next above the sea is the air, diversified by day and night: when
rarefied, it possesses the higher region; when condensed, it turns into
clouds, and with the waters which it gathers enriches the earth by the
rain. Its agitation produces the winds. It causes heat and cold
according to the different seasons. It sustains birds in their flight;
and, being inhaled, nourishes and preserves all animated beings.

XL. Add to these, which alone remaineth to be mentioned, the firmament
of heaven, a region the farthest from our abodes, which surrounds and
contains all things. It is likewise called ether, or sky, the extreme
bounds and limits of the universe, in which the stars perform their
appointed courses in a most wonderful manner; among which, the sun,
whose magnitude far surpasses the earth, makes his revolution round it,
and by his rising and setting causes day and night; sometimes coming
near towards the earth, and sometimes going from it, he every year
makes two contrary reversions[165] from the extreme point of its
course. In his retreat the earth seems locked up in sadness; in his
return it appears exhilarated with the heavens. The moon, which, as
mathematicians demonstrate, is bigger than half the earth, makes her
revolutions through the same spaces[166] as the sun; but at one time
approaching, and at another receding from, the sun, she diffuses the
light which she has borrowed from him over the whole earth, and has
herself also many various changes in her appearance. When she is found
under the sun, and opposite to it, the brightness of her rays is lost;
but when the earth directly interposes between the moon and sun, the
moon is totally eclipsed. The other wandering stars have their courses
round the earth in the same spaces,[167] and rise and set in the same
manner; their motions are sometimes quick, sometimes slow, and often
they stand still. There is nothing more wonderful, nothing more
beautiful. There is a vast number of fixed stars, distinguished by the
names of certain figures, to which we find they have some resemblance.

XLI. I will here, says Balbus, looking at me, make use of the verses
which, when you were young, you translated from Aratus,[168] and which,
because they are in Latin, gave me so much delight that I have m