must be formed of the astronomical knowledge of the Chaldeans. It is
natural enough to think, that a people who inhabited vast plains,
under a sky perpetually serene, must have been led to observe the
course of the stars, even at a period when they still led a wandering
life, and when the stars alone could direct their courses during
the night; but since what period were they astronomers, and to what
perfection did they carry the science? Here rests the question. It is
generally allowed that Callisthenes sent to Aristotle observations
made by them, and which referred to a period of 2200 years before
Christ; but this fact is related only by Simplicius[201], as stated
upon the authority of Porphyry, and 600 years after Aristotle.
Aristotle himself says nothing on the subject, nor has any creditable
astronomer spoken of it. Ptolemy mentions and makes use of ten
observations of eclipses really made by the Chaldeans; but they do
not refer to an earlier period than that of Nabonassar (721 years
before Christ); they are inaccurate also; the time is expressed only
in hours and half-hours, and the shadow only in halves or fourths of
the diameter. Notwithstanding, as they had fixed dates, the Chaldeans
must have had some knowledge of the true length of the year, and some
means of measuring time. They appear to have known the period of
eighteen years, which brings back the eclipses of the moon in the
same order; a piece of knowledge which the mere inspection of their
registers would promptly afford them; but it is certain that they
could neither explain nor predict eclipses of the sun.
It is from not having sufficiently understood a passage of Josephus,
that Cassini, and after him Bailly, have imagined that they
discovered in it a luni-solar period of 600 years, which had been
known from the time of the first patriarchs[202].
Thus every thing leads us to believe that the great reputation of the
Chaldeans was given them at a more recent period, by their unworthy
successors, who, under the same name, sold their horoscopes and
predictions throughout the whole Roman empire, and who, in order to
procure themselves more credit, attributed to their rude ancestors
the honour of the discoveries of the Greeks.
With regard to the Indians, every body knows that Bailly, believing
that the epoch which is used as a period of departure in some of
their astronomical tables had been actually observed, has attempted
to draw from thence a proof of the great antiquity of the science
among this people, or at least among the nation which had bequeathed
them its knowledge. But the whole of this system, invented with so
much labour, falls to the ground of itself, now that it is proved
that this epoch has been adopted but of late, from calculations made
backwards, and even false in their results.[203]
Mr Bentley has discovered that the tables of Tirvalour, on which the
assertion of Bailley especially rested, must have been calculated
about 1281 of the Christian era, or 540 years ago, and that the
Surya-Siddhanta, which the Brahmins regard as their oldest scientific
treatise on astronomy, and which they pretend to have been revealed
upwards of 20,000,000 of years ago, could not have been composed at
an earlier period than about 760 years from the present day[204].
Solstices and equinoxes indicated in the Pouranas, and calculated
according to the positions which seem to be attributed to them by the
signs of the Indian zodiac, such as they are supposed to be, have
acquired the character of an enormous antiquity. A more attentive
examination of these signs or nacchatras has lately convinced M.
de Paravey that reference is only made to solstices of 1200 years
before the Christian era. This author at the same time admits, that
the place of the solstices is so inaccurately fixed, that this
determination of their date must be received with a latitude of 200
or 300 years. They are in the same predicament as those of Eudoxus
and of Tcheoukong[205].
It is ascertained that the Indians do not make observations, and that
they are not in possession of any of the instruments necessary for
that purpose. M. Delambre indeed admits, with Bailly and Legentil,
that they have processes of calculation, which, without proving the
antiquity of their astronomy, shew at least its originality[206];
and yet this conclusion can by no means be extended to their sphere;
for, independently of their twenty-seven nacchatras or lunar houses,
which strongly resemble those of the Arabians, they have the same
twelve constellations in the zodiac as the Egyptians, Chaldeans,
and Greeks[207]; and, if we refer to Mr Wilfort’s assertions, their
extra-zodiacal constellations are also the same as those of the
Greeks, and bear names which are merely slight alterations of their
Greek names[208].
It is to Yao that the introduction of astronomy into China is
attributed. He is represented, in the Chou-king, as sending
astronomers toward the four cardinal points of his empire, to
examine what stars presided over the four seasons, and to regulate
the operations to be carried on at each period of the year[209], as
if their dispersion was necessary for such an undertaking. About
200 years later, the Chou-king speaks of an eclipse of the sun, but
accompanied with ridiculous circumstances, as in all the fables of
this kind; for the whole Chinese army, headed by a general, is made
to march against two astronomers, because they had not properly
predicted it[210]; and it is well known that, more than 2000 years
after, the Chinese astronomers possessed no means of accurately
predicting the eclipses of the sun. In 1629 of our era, at the time
of their dispute with the Jesuits, they did not even know how to
calculate the shadows.
The real eclipses, recorded by Confucius in his Chronicle of the
kingdom of Lou, commence only 1400 years after this, in the 776th
before Christ, and scarcely half a century earlier than those of the
Chaldeans related by Ptolemy. So true is it, that the nations which
escaped at the same time from the general catastrophe, also arrived
about the same period, when their circumstances have been similar,
at the same degree of civilization. Now, it might be thought, from
the identity of the names of the Chinese astronomers in different
reigns (they appear, according to the Chou-king, to have all been
named _Hi_ and _Ho_), that, at this remote epoch, their profession
was hereditary in China, as it was in India, Egypt, and Babylon.
The only Chinese observation of any antiquity, which has nothing in
itself to prove its want of authenticity, is that of the shadow made
by _Tcheou-kong_ about 1100 years before Christ; and even it is far
from being correct[211].
Hence our readers may conclude, that the inferences drawn from the
alleged perfection of astronomical science among ancient nations, is
not more conclusive in favour of the excessive antiquity of those
nations, than the testimonies which they have adduced in reference to
themselves.
But had this astronomy been more perfect, what would it prove?
Has the progress been calculated which this science ought to make
among nations who were not in any degree in possession of others;
to whom the serenity of the sky, the necessities of the pastoral or
agricultural life, and their superstitious ideas, would render the
stars an object of general attention; where colleges, or societies
of the most respectable men among them, were charged with keeping a
register of interesting phenomena, and transmitting their memory; and
where, from the hereditary nature of the profession, the children
were brought up from the cradle in the knowledge of facts ascertained
by their parents? Supposing that, among the numerous individuals of
whom the cultivation of astronomy was the sole occupation, there
should happen to be one or two possessed of extraordinary talents
for geometry, all the knowledge acquired by these nations might be
attained in a few centuries.
Since the time of the Chaldeans, real astronomy has only had two
eras, that of the Alexandrian school, which lasted 400 years, and
that of our own times, which has not existed so long. The learned
period of the Arabians scarcely added any thing to it; and the other
ages have been mere blanks with regard to it. Three hundred years did
not intervene between Copernicus and the author of the _Mecanique
Céleste_; and can it be believed that the Indians required thousands
of years to arrive at their crude theories?
_The Astronomical Monuments left by the Ancients do not bear the
excessively remote dates which have been attributed to them._
Recourse has therefore been had to arguments of another kind. It
has been pretended that, independently of the knowledge which these
nations may have acquired, they have left monuments which bear a date
fixed by the state of the heavens which they represent, and one that
refers to a very remote antiquity. The zodiacs sculptured in two
temples of Upper Egypt, are adduced as furnishing proofs perfectly
demonstrative of this assertion. They present the same figures of
the zodiacal constellations as are employed at the present day,
but distributed in a manner peculiar to themselves. The state of
the heavens at the period when these monuments were delineated, is
imagined to have been represented by this distribution, and it has
been thought that it would be possible from it to infer the precise
period at which the edifices containing them were erected[212].
But to arrive at the high antiquity which is supposed to be deducible
from this, it must, in the _first_ place, be supposed, that their
division has a determinate relation to a certain state of the
heavens, dependent upon the precession of the equinoxes, which causes
the colures to make the tour of the zodiac in 26,000 years; that
it indicated, for example, the position of the solstitial point;
and, _secondly_, that the state of the heavens represented was
precisely that which took place at the period when the monument was
erected,--two suppositions which themselves, as is evident, suppose
a great number of others.
In point of fact, are the figures of these zodiacs the
constellations,--the true groups of stars which at present bear the
same names, or merely what astronomers call signs, that is to say,
divisions of the zodiac proceeding from one of the colures, whatever
place this colure occupies? Is the point at which these zodiacs
have been divided into two bands, necessarily that of a solstice?
Is the division of the side next the entrance, necessarily that of
the summer solstice? Does this division indicate, even in general, a
phenomenon dependent upon the precession of the equinoxes? Does it
not refer to some period the rotation of which would be less; for
example, to the moment of the tropical year when such or such sacred
years of the Egyptians commenced, which, being shorter than the true
tropical year by nearly six hours, would make the tour of the zodiac
in 1508 years? Lastly, whatever signification it may have had, has it
been intended by it to mark the time when the zodiac was sculptured,
or that when the temple was built? Has not the object been to record
a previous state of the heavens at some period which was interesting
in a religious point of view, whether it had been actually observed,
or inferred from a retrograde calculation?
From the mere announcement of such questions, it will be perceived
how complicated they necessarily are, how much subject to
controversy any solution that might be adopted on this subject would
be, and how little qualified to serve as a solid proof, for the
solution of another problem, such as the antiquity of the Egyptian
nation. And it may be said, with regard to those who have attempted
to infer a date from these data, that there have arisen as many
opinions as there have been authors.
The learned astronomer Mr Burkhard, from a first examination, judged
that, at Dendera, the solstice is marked by the Lion; which would
make it two signs less remote than at the present day, and the
temple at least 4000 years old[213]. He gave, at the same time an
antiquity of 7000 years to that of Esne, although it is not known
how he had purposed to reconcile these numbers with what we know
of the precession of the equinoxes. The late M. Lalande, seeing
that the Cancer was repeated on the two bands, imagined that the
solstice passed to the middle of that constellation; but as this
was the case also in the sphere of Eudoxus, he concluded that some
Grecian artist might have represented this sphere on the ceiling of
an Egyptian temple, without knowing that it represented a state of
the heavens which no longer existed[214]. This, as is seen, was a
conclusion very different from that of Mr Burkhard. Dupuis was the
first who thought it necessary to search for proofs of the idea,
in some measure confidently adopted, that it was the solstice that
was denoted. He found them, with reference to the great zodiac of
Dendera, in the globe on the top of the pyramid, and in several
emblems placed near different signs, and which he imagined, sometimes
according to the opinion of ancient authors, such as Plutarch, Horus
Apollo, or Clement of Alexandria, sometimes according to his own
conjectures, ought to be regarded as representing phenomena which
had been really those of the seasons affected at each sign. As for
the rest, he maintained that this state of the heavens affords the
date of the monument, and that it is the original, and not a copy, of
the sphere of Eudoxus, that was represented at Dendera, which would
refer it to a period of 1468 years before Christ, or to the reign of
Sesostris. The number of nineteen boats, however, placed under each
band, furnished him with the idea that the solstice might probably
have been at the nineteenth degree of the sign, which would make it
288 years older[215].
Mr Hamilton[216] having remarked, that, at Dendera, the Scarabæus
belonging to the side of the ascending signs is smaller than that of
the other side, an English author[217] has concluded from this that
the solstice may have been nearer its actual point than the middle
of the Cancer, which would carry us back to a period of 1000 or 1200
years before Christ.
The late M. Nouet, judging that the globe, the rays, and the horned
head, or head of Isis, represent the heliacal rising of Sirius,
supposed that it was intended to mark an epoch of the Sothian
period, but that it was intended to mark it by the place which the
solstice occupied. Now, in the last but one of these periods, that
which elapsed between 2782 and 1322 before Christ, the solstice had
passed from 30° 48′ of the constellation of the Lion to 13° 34′ of
Cancer. At the middle of this period, it was therefore at 23° 34′ of
cancer. The heliacal rising of Sirius happened then some days after
the solstice; and this is nearly what has been indicated, according
to M. Nouet, by the repetition of the Scarabæus, and by the figure
of Sirius with the rays of the sun placed at the commencement of the
band to the right. Calculating upon this basis, he concludes that the
temple of Dendera was built 2052 years before Christ, and that of
Esne 4600[218].
All these calculations, even admitting that the division marks the
solstice, would still be susceptible of many modifications; and, at
first, it appears that their authors have supposed the constellations
all of thirty degrees like the signs, and have not reflected that
it is far from being the case that they are thus equal, at least
as they are represented at the present day, and as the Greeks have
transmitted them to us. In reality, the solstice, which is at present
on this side of the first stars of the constellation of Gemini,
could only have left the first stars of the constellation of Cancer
forty-five years before Christ, and had left the constellation of Leo
only 1260 years before the same era.
* * * * *
My distinguished and learned colleague, M. Delambre, has favoured me
with the following table and remarks, which illustrate what has been
above said.
_TABLE of the Extent of the Zodiacal Constellations, as they are
designed upon our Globes, and of the Times required by the Colures
to traverse them._
+------------------------------------------------------+
| |
| ARIES. |
| |
+----------+-------------------+-----------+-----------+
| Stars. |Longitudes in 1800.|Year of the|Year of the|
| | | Equinox. | Solstice. |
+----------+-------------------+-----------+-----------+
| γ | 1^s 0° 23′ 40″ | -389 | 6869 |
| β | 1 1 10 40 | -441 | 6921 |
| α | 1 4 52 0 | -710 | 7190 |
| η | 1 5 18 50 | -742 | 7222 |
| 2 θ | 1 6 14 16 | -810 | 7290 |
| ζ | 1 19 8 50 | -1739 | 8219 |
| τ tail. | 1 20 51 0 | -1862 | 8342 |
+----------+-------------------+-----------+-----------+
| Dur. | 20 27 20 | 1473 | 1473 |
+----------+-------------------+-----------+-----------+
| |
| TAURUS. |
| |
+----------+-------------------+-----------+-----------+
| ξ | 1^s 19° 6′ 0″ | -1735 | -8215 |
| η | 1 27 12 0 | -2318 | -8798 |
| α | 2 6 59 40 | -3024 | -9504 |
| β | 2 19 47 0 | -3944 | -10424 |
| ζ | 2 22 0 0 | -4104 | -10584 |
| a Coch. | 2 24 42 40 | -4300 | -10780 |
+----------+-------------------+-----------+-----------+
| Dur. | 35 36 40 | 2565 | 2565 |
+----------+-------------------+-----------+-----------+
| |
| GEMINI. |
| |
+----------+-------------------+-----------+-----------+
| Propus. | 2^s 28° 9′ 20″ | -4547 | -11027 |
| η | 3 0 39 0 | -4727 | -11207 |
| γ | 3 6 18 40 | -5134 | -11614 |
| δ | 3 15 44 0 | -5813 | -12293 |
| Castor. | 3 17 27 30 | -5937 | -12417 |
| Pollux. | 3 20 28 9 | -6154 | -12634 |
| φ | 3 22 27 10 | -6926 | -12776 |
+----------+-------------------+-----------+-----------+
| Dur. | 24 17 40 | 1749 | 1749 |
+----------+-------------------+-----------+-----------+
+------------------------------------------------------+
| |
| CANCER. |
| |
+----------+-------------------+-----------+-----------+
| Stars. |Longitudes in 1800.|Year of the|Year of the|
| | | Equinox. | Solstice. |
+----------+-------------------+-----------+-----------+
| 1 ω | 3^s 24° 21′ 55″ | 6475 | +45 |
| ζ | 3 28 32 0 | 6734 | -254 |
| β | 4 1 28 20 | 6906 | -426 |
| γ | 4 4 45 0 | 7182 | -702 |
| 1 α | 4 10 18 50 | 7583 | -1103 |
| 2 α | 4 10 50 36 | 7621 | -1141 |
| χ | 4 13 23 0 | 7804 | -1324 |
+----------+-------------------+-----------+-----------+
| Dur. | 19 1 5 | 1369 | 1369 |
+----------+-------------------+-----------+-----------+
| |
| LEO. |
| |
+----------+-------------------+-----------+-----------+
| χ | 4^s 12° 30′ 0″ | -7740 | -1260 |
| α | 4 27 3 10 | -8788 | -1908 |
| δ | 5 8 30 0 | -9612 | -3132 |
| β | 5 18 50 55 | -10357 | -3877 |
| ... | .. ... ... ... | ..... | ..... |
| ... | .. ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 36 20 55 | 2617 | 2617 |
+----------+-------------------+-----------+-----------+
| |
| VIRGO. |
| |
+----------+-------------------+-----------+-----------+
| ω | 5^s 19° 2′ 22″ | -10371 | -3891 |
| β | 5 24 19 0 | -10750 | -4271 |
| η | 6 2 2 40 | -11307 | -4827 |
| δ | 6 8 41 40 | -11786 | -5306 |
| α | 6 21 3 15 | -12676 | -6196 |
| λ | 7 4 9 50 | -13620 | -7140 |
| μ | 7 7 17 40 | -13845 | -7365 |
+----------+-------------------+-----------+-----------+
| Dur. | 48 15 18 | 3474 | 3474 |
+----------+-------------------+-----------+-----------+
| Mean | | | |
| Dur. | 30 0 0 | 2160 | |
+----------+-------------------+-----------+-----------+
+------------------------------------------------------+
| |
| LIBRA. |
| |
+----------+-------------------+-----------+-----------+
| Stars. |Longitudes in 1800.|Year of the|Year of the|
| | | Equinox. | Solstice. |
+----------+-------------------+-----------+-----------+
| 1 α | 7^s 11° 0′ 44″ | -14113 | -7633 |
| 2 α | 7 12 18 0 | -14246 | -7926 |
| β | 7 16 35 0 | -14514 | -8034 |
| γ | 7 22 20 34 | -14929 | -8449 |
| γ Scorp. | 7 27 41 0 | -15312 | -8832 |
| ξ | 7 28 30 15 | -15372 | -8892 |
| ... | .. ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 17 29 31 | 1259 | 1259 |
+----------+-------------------+-----------+-----------+
| |
| SCORPIO. |
| |
+----------+-------------------+-----------+-----------+
| 1 Α | 7^s 28° 50′ 6″ | -15396 | -8916 |
| β | 8 0 23 48 | -15508 | -9028 |
| α | 8 6 57 38 | -15980 | -9500 |
| ζ | 8 12 35 30 | -16387 | -9907 |
| λ | 8 21 47 27 | -17049 | -105569 |
| ... | .. ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 22 57 21 | 1653 | 1653 |
+----------+-------------------+-----------+-----------+
| |
| SAGITTARIUS. |
| |
+----------+-------------------+-----------+-----------+
| γ | 7^s 28° 28′ 20″ | -17530 | -11050 |
| λ | 9 3 32 56 | -17895 | -11415 |
| ζ | 9 10 50 28 | -18421 | -11941 |
| ψ | 9 14 15 15 | -18667 | -12187 |
| ω | 9 23 2 19 | -19299 | -12819 |
| g | 9 25 39 25 | -19487 | -13007 |
| ... | .. ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 27 11 50 | 1957 | 1957 |
+----------+-------------------+-----------+-----------+
+----------+-------------------+-----------+-----------+
| |
| CAPRICORN. |
| |
+----------+-------------------+-----------+-----------+
| Stars. |Longitudes in 1800.|Year of the|Year of the|
| | | Equinox. | Solstice. |
+----------+-------------------+-----------+-----------+
| 1^{er} | 9^s 29° 39′ 15″ | -19775 | -13295 |
| 2 α | 10 1 3 58 | -19877 | -13397 |
| β | 10 1 15 30 | -19891 | -13411 |
| ι | 10 14 53 30 | -20872 | -14392 |
| γ | 10 18 59 28 | -21166 | -14586 |
| μ | 10 23 1 12 | -21458 | -14978 |
| ν | .. ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 23 21 17 | 1683 | 1683 |
+----------+-------------------+-----------+-----------+
| |
| AQUARIUS. |
| |
+----------+-------------------+-----------+-----------+
| ε | 10^s 8° 56′ 0″ | -20444 | -13964 |
| β | 10 20 36 30 | -21285 | -14805 |
| α | 11 0 34 0 | -22001 | -15521 |
| ζ | 11 6 7 0 | -22400 | -15920 |
| 2 ψ | 11 13 56 12 | -22963 | -16483 |
| 5 Α | 11 18 3 28 | -23260 | -16780 |
+----------+-------------------+-----------+-----------+
| Dur. | 39 7 28 | 2816 | 2816 |
+----------+-------------------+-----------+-----------+
| |
| PISCES. |
| |
+----------+-------------------+-----------+-----------+
| β | 11^s 15° 49′ 0″ | 23095 | 16615 |
| λ | 11 23 49 0 | 23675 | 17195 |
| δ | 12 11 22 0 | 24939 | 18459 |
| σ | 12 24 26 0 | 25879 | 19399 |
| α | 12 26 34 58 | 26034 | 19554 |
| |... ... ... ... | ..... | ..... |
| |... ... ... ... | ..... | ..... |
+----------+-------------------+-----------+-----------+
| Dur. | 40 45 58 | 2939 | 2939 |
+----------+-------------------+-----------+-----------+
| | | 0° | 270^s |
|Sirius | 3 11 20 10 | -5487 | -18447 |
+----------+-------------------+-----------+-----------+
_Construction and Use of the Table._
“The longitudes of the stars, for 1800, have been taken from the
Berlin Tables, and are those of Lacaille, Bradley, or Flamstead. The
first and the last of each constellation have been taken, as well as
some of the brightest of the intermediate stars. The third column
indicates the year in which the longitude of the star was 0′, that
is to say, that in which the star was in the equinoxial colure of
spring. The last column indicates the year when the star was in the
solstitial colure, whether of winter or of summer.
“For Aries, Taurus, and Gemini, the winter solstice has been chosen;
for the other constellations the summer solstice has been chosen,
for the sake of not receding into too remote antiquity, and of not
approaching too near modern times. It will be easy to find the
opposite solstice, by adding the semiperiod of 12,960 years. The same
rule will serve for finding the time when the star has been, or will
be, at the autumnal equinox.
“The sign - indicates the years before our era, the sign + the
year of our era; and the last line, at the end of each sign under
the title of _duration_, gives the extent of the constellation in
degrees, and the time which the equinox, or the solstice, occupies in
traversing the constellation from one end to the other.
“The precession of 50″ yearly has been supposed, this being the
result of the comparison of the catalogue of Hipparchus with the
modern catalogues. We have thus the advantage of round numbers, and a
general accuracy that may be relied upon. The entire period is thus
25,920 years; the semiperiod, 12,960 years; the quarter period, 6480
years; the twelfth, or a sign, 2160 years.