CHAP. 57. (25.)—ARRANGEMENT OF THE STARS ACCORDING TO THE
TERRESTRIAL DAYS AND NIGHTS.
In the first place, it is almost an utter impossibility to
calculate with a fair degree of accuracy the days of the year and
the movements of the sun. To the three hundred and sixty-five days
there are still to be added the intercalary days, the
result of the additional quarters of a day and night: hence it
is, that it is found impossible to ascertain with exactness the
proper periods for the appearance of the stars. To this we
must add, too, a certain degree of uncertainty connected with
these matters, that is universally admitted; thus, for instance,
bad and wintry weather will often precede, by several days,
the proper period for the advent of that season, a state of things
known to the Greeks as
προχειμάζειν;1 while at another time,
it will last longer than usual, a state of circumstances known as
ἐπιχειμάζειν.2 The effects, too, of the changes that
take place
in the seasons will sometimes be felt later, and at other times
earlier, upon their reaching the face of the earth; and we not
unfrequently hear the remark made, upon the return of fine
weather, that the action of such and such a constellation is
now completed.
3 And then, again, as all these phænomena
depend upon certain stars, arranged and regulated in the vault of
heaven, we find intervening, in accordance with the movements
of certain stars, hailstorms and showers, themselves productive
of no slight results, as we have already observed,
4 and apt to
interfere with the anticipated regular recurrence of the seasons.
Nor are we to suppose that these disappointments fall upon the
human race only, for other animated beings, as well as ourselves,
are deceived in regard to them, although endowed with even a
greater degree of sagacity upon these points than we are, from
the fact of their very existence depending so materially upon
them. Hence it is, that we sometimes see the summer birds
killed by too late or too early cold, and the winter birds by
heat coming out of the usual season. It is for this reason,
that Virgil
5 has recommended us to study the courses of the
planets, and has particularly warned us to watch the passage
of the cold star Saturn.
There are some who look upon the appearance of the butterfly as the surest sign of spring, because of the extreme delicacy
of that insect. In this present year,
6 however, in which I
am penning these lines, it has been remarked that the flights
of butterflies have been killed three several times, by as many
returns of the cold; while the foreign birds, which brought
us by the sixth of the calends of February
7 every indication
of an early spring, after that had to struggle against a winter
of the greatest severity. In treating of these matters, we have
to meet a twofold difficulty: first of all, we have to ascertain
whether or not the celestial phænomena are regulated by
certain laws, and then we have to seek how to reconcile those
laws with apparent facts. We must, however, be more particularly
careful to take into account the convexity of the earth,
and the differences of situation in the localities upon the face
of the globe; for hence it is, that the same constellation shows
itself to different nations at different times, the result being,
that its influence is by no means perceptible everywhere at the
same moment. This difficulty has been considerably enhanced,
too, by various authors, who, after making their observations
in different localities, and indeed, in some instances, in the same
locality, have yet given us varying or contradictory results.
There have been three great schools of astronomy, the Chaldæan,
the Ægyptian, and the Grecian. To these has been
added a fourth school, which was established by the Dictator
Cæsar among ourselves, and to which was entrusted the duty
of regulating the year in conformity with the sun's revolution,
8
under the auspices of Sosigenes, an astronomer of considerable
learning and skill. His theory, too, upon the discovery of certain
errors, has since been corrected, no intercalations having
been made for twelve
9 successive years, upon its being found
that the year which before had anticipated the constellations,
was now beginning to fall behind them. Even Sosigenes himself, too,
though more correct than his predecessors, has not
hesitated to show, by his continual corrections in the three
several treatises which he composed, that he still entertained
great doubts on the subject. The writers, too, whose names are
inserted at the beginning of this work,
10 have sufficiently
revealed the fact of these discrepancies, the opinions of one being
rarely found to agree with those of another. This, however,
is less surprising in the case of those whose plea is the difference
of the localities in which they wrote. But with reference to
those who, though living in the same country, have still arrived
at different results, we shall here mention one remarkable
instance of discrepancy. Hesiod—for under his name, also,
we have a treatise extant on the Science of the Stars
11—has
stated that the morning setting of the
Vergiliæ takes place at
the moment of the autumnal equinox; whereas Thales, we
find, makes it the twenty-fifth day after the equinox, Anaximander
the twenty-ninth, and Euctemon the forty-eighth.
As for ourselves, we shall follow the calculations made by
Julius Cæsar,
12 which bear reference more particularly to Italy;
though at the same time, we shall set forth the dicta of various
other writers, bearing in mind that we are treating not of an
individual country, but of Nature considered in her totality.
In doing this, however, we shall name, not the writers themselves,
for that would be too lengthy a task, but the countries
in reference to which they speak. The reader must bear in
mind, then, that for the sake of saving space, under the head
of Attica, we include the islands of the Cyclades as well; under
that of Macedonia, Magnesia and Thracia; under that of Egypt,
Phœnice, Cyprus, and Cilicia; under that of Bœotia, Locris,
Phocis, and the adjoining countries; under that of Hellespont,
Chersonesus, and the contiguous parts as far as Mount Athos;
under that of Ionia, Asia
13 and the islands of Asia; under that
of Peloponnesus, Achaia, and the regions lying to the west of
it. Chaldæa, when mentioned, will signify Assyria and Babylonia, as well.
My silence as to Africa,
14 Spain, and the provinces of Gaul,
will occasion no surprise, from the fact that no one has published
any observations made upon the stars in those countries.
Still, however, there will be no difficulty in calculating them,
even for these regions as well, on reference being made to the
parallels which have been set forth in the Sixth Book.
15 By
adopting this course, an accurate acquaintance may be made
with the astronomical relations, not only of individual nations,
but of cities even as well. By taking the circular parallels
which we have there appended to the several portions of the
earth respectively, and applying them to the countries in question,
that are similarly situate, it will be found that the rising
of the heavenly bodies will be the same for all parts within
those parallels, where the shadows projected are of equal length.
It is also deserving of remark, that the seasons have their
periodical recurrences, without any marked difference, every
four years, in consequence of the influence
16 of the sun, and that
the characteristics of the seasons are developed in excess every
eighth year, at the revolution of every hundredth moon.