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ON THE REVOLUTIONS OF

CONSTRUCTION AND USE OF THE TABLE.

"The longitude of the stars for 1800, have been
taken from the Berlin Tables, as calculated by
Lacaille, Bradley, or Flamstead.
"The first and last of each constellation, and some
of the most brilliant intermediate stars have been
taken. The third column indicates the year when the
longitude of the star was 0; that is, the year when the
star was in the equinoctial colure of spring. The last
column marks the year when the star was in the
solstitial colure, either of winter or summer.
"For the Ram, the Bull and the Twins, the winter
solstice has been chosen; for the other constellations,
the summer solstice has been chosen, that the extreme
might be avoided of going too remotely into antiquity,
or approaching too closely to modern times. Besides, it
will be easy to find the opposite solstice, by adding the
semi-period of 12,960 years. The same rule applies for
finding the time when a 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 name of 'Duration,' gives the
extent of the constellation in degrees, and the time that
the equinox or the solstice employs in traversing the
constellation from one end to the other.
"Fifty seconds per annum have been taken as the
precession, as it is given by a comparison of the
catalogue of Hipparchus with modern

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catalogues. This gave the convenience of round
numbers, and an exactness that may be depended on.
Thus the entire period is 25,920 years; the half period
12,960 years; the quarter 6480 years; the twelfth, or a
sign, 2160 years.
We must observe that the constellations leave spaces
between, and that sometimes they infringe on each
other. Thus, between the last star of Scorpio, and the
first of Sagittarius there is an interval of six degrees
and two-thirds; on the contrary, the last of Capricornus
is more advanced by fourteen degrees of longitude than
the first of Aquarius.
"Independently of the inequality of the motion of
the sun, the constellations would give a very unequal
and faulty measurement of the year and months. The
signs of thirty degrees afford a more convenient and
less defective method. But the signs are only a
geometric supposition; we can neither distinguish nor
observe them; they are continually changing their
places by the retrogradation of the equinoctial point.
"We have always been able to calculate roughly the
equinoxes and soistices; and we have remarked, that
the spectacle of the heavens during the night was not
any longer exactly the same as it had been anciently at
the times of the equinoxes and soistices. We have
never been able to observe accurately the heliacal
rising of a star; we must be a few day out of the
calculation, and thus we often speak without having a
positive period from which we could reckon. Before
Hipparchus we do not find, either from books or
traditions any thing whence we may calculate, and this
has caused a multiplicity of systems. We have disputed
without having a knowledge of the subject. Those who
are not astronomers may form

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ON THE REVOLUTIONS OF

their own ideas of the science of the Chaldeans, the
Egyptians, &c. &c.; no real inconvenience will result.
We may assign to these people the intelligence and
wisdom of the moderns, but we can borrow nothing
from them; for either they had nothing to leave, or
have left nothing. Astronomers will never draw from
the ancients any thing of the smallest utility. Let us
then leave to the learned vain conjectures, and confess
our positive ignorance of things useless in themselves,
and of which there is not a single existing record.
"The limits of the constellations vary according to
the authors that we consult. We see these limits expand
or contract where they impress, from Hipparchus to
Tycho, from Tycho to Hevelius, from Hevelius to
Flamstead, Lacaille, Bradley, or Piazzi.
"I have said elsewhere, that the constellations were
of no use, only that at best they enable us more easily
to find out the stars, whilst the stars themselves point
out particularly the fixed points whence we may refer
the motions of the colures or the planets. Astronomy
only began at the period when Hipparchus made the
first catalogue of stars, measured the revolution of the
sun, the moon, and their principal inequalities. All the
rest is involved in darkness, uncertainty, and gross
errors. It would be lost time to endeavour to explain or
search into the chaos.
"Excepting a few particulars, I have said all that I
think on the subject. I do not pretend to make
converts: it is of little consequence who may or may
not adopt my opinions; but if my arguments be
compared with the speculations of Newton, Herschel,
Bailly, and many others, it is not impossible

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that in time these chimeras, more or less brilliant, may
not be relished.
"I have endeavoured to determine the extent of the
constellations after the catasterisms of the false
Eratosthenes. The thing is really impossible. It would
be still worse if Hyginus, and particularly Firmicus,
are consulted. I subjoin what I have extracted from
Eratosthenes.

"As to the Chaldeans, Egyptians, Chinese, and
Indians, we must not think of them. We can, in fact,
get nothing from them. My opinion is expressed in the
preliminary discourse of my History of the Astronomy
of the Middle Age, pp. 17 and 18.

* Eratosthenes makes only one constellation of Scorpio and the Talons.
He makes the commencement of the latter without fixing the end; and, as he
gives 1823 years to Scorpio, properly so called, there would remain 1089
years for the Talons, supposing that there was no space between the two
constellations.

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"See also the note added to the Report on the Memoirs
of M. de Paravey, vol. viii. of the New Annals of
Voyages, and re-published by M. de Paravey in his
Summary of his Memoirs on the Origin of the Sphere,
pp. 24, and from 31 to 36. See also the Analysis of the
Mathematical Labours of the Academy in 1820, pp.78
and 79.
"DELAMBRE"

We should still have to ascertain when they ceased
to place the constellation in which the sun entered
after the solstice, at the head of the descending signs,
and whether that took place immediately that the
solstice had retrograded, so as to touch the preceding
constellation.
Thus, MM. Jollois and Devilliers, to whose
unremitting ardour we are indebted for our knowledge
of these famous monuments, always taking the division
towards the entrance of the vestibule as the solstice,
and judging that Virgo must have been the first of the
descending constellations, considering that the solstice
had not receded at least as far as to the middle of the
constellation of Leo; and thinking, moreover, as we
have observed, that Leo is divided in the great zodiac
of Esne, only make the zodiac as remote as 2610 years
before Christ. (1)
Mr. Hamilton, the first who observed the division of
the sign of Leo in the zodiac of Esne, reduced the
distance of the period of the solstice there to 1400
years before Christ.
Many other systems on this subject have appeared.
Mr. Rhode, for instance, proposed two. The first made
the date of the zodiac of the portico

(1) See the great work on Egypt. Ant. Mem. vol. i. p. 486.

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at Dendera, 591 years before Christ, the second fixes it
at 1290.(1) M. Latreille assumed the epoch of this
zodiac at 670 years before Christ; that of the
planisphere at 550; that of the zodiac of the great
temple of Esne at 2550; and that of the smaller at
1760.
But there was a vital difficulty in all these dates,
which set out on the twofold supposition that the
division marks the solstice, and that the position of the
solstice marks the epoch of the monument. The
unavoidable result is, that the zodiac of Esna must be
at least 2000, and perhaps 3000(2) years more ancient
than that of Dendera, a consequence which evidently
destroys the supposition; for no man, with the slightest
knowledge of the history of the arts, can believe that
two edifices so strikingly similar in their architecture
have been built at periods so widely remote from each
other.
The feeling of this impossibility; united with the
belief that this division of the zodiacs marks a date,
give rise to the conjecture, that it was intended to
mark the period of the sacred years of the Egyptians,
when the monument was constructed. These years only
lasting three hundred and sixty-five days, if the sun, at
the commencement of one, was at the commencement
of a constellation, he would be six hours backward at
the same time in the commencement of the following
year, and after one hundred and twenty-one years, he
would have

(1) Rhode's Essay on the Age of the Zodiac, and Origin of
Constellations, in German, 1809, p. 78.
(2) According to the tables given above, the solstice remained 3474, or at
least 3307 years in the constellation Virgo, which occupies the greatest
space in the zodiac; and 2617 in that of Leo.

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retrogaded to the commencement of the preceding sign.
It seems probable enough that the builders of a
temple would have wished to indicate as nearly as
possible in what period of the great year, or sothaic
year, it was erected; and the indication of the sign
which then commenced the sacred year, was the best
possible means of effecting this. We should thus find
that one hundred and twenty or one hundred and fifty
years had elapsed between the build ng of the temple at
Esne, and that at Dendera.
But, by this View of the case, it still remained to be
determined, in which of the great years these erections
took place; in that which finished one hundred and
thirty-eight years after; or in that which terminated
1322 years before Christ, or in some other.
Visconti, the author of this hypothesis, taking the
sacred year, whose commencement corresponded with
the sign of Leo, and judging from the similarity of
these signs, that they had been represented at an epoch
when the opinions of the Greeks were not unknown in
Egypt, could only choose the end of the last great
year, or the space that elapsed between the year
twelve, and the year one hundred and thirty-eight after
Christ,(1) which seemed to him to agree with the
Greek inscription, of which however he knew but
little, but had heard that it made some mention of one
of the Cæsars.
M. Testa, seeking the dates of the monument by
another train of reasoning, supposed, that as Virgo is
at Esne at the head of the zodiac, it was intended to
depict the era of the battle of Actium, as it was

(1) Translation of Herodotus, by Larcher, v. ii. p. 570.

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established in Egypt, by a decree of the senate, cited
by Dion Cassius, and which began in the month of
September, or the day on which Augustus took
Alexandria. (1)
M. de Paravey considered these zodiacs in a novel
point of view, which embraces at once both the
revolution of the equinoxes, and those of the great
year. Supposing that the circular planisphere of
Dendera must have been placed towards the east, and
that the axis from north to south is the line of the
solstices, he found the summer solstice at the second of
Gemini; that of the winter solstice at the tail of
Sagittarius; and the line of the equinoxes would have
passed through Pisces and Virgo, which would give
him the first century of our era for a date.
By this method, the division of the zodiac of the
portico could no longer have any relation to the
colures, and it would be necessary to seek else where
for the mark of the solstice. M. de Paravey, having
remarked that between all the signs there were female
figures bearing a star on their heads, and going in the
same direction; and noticing that the female only who
follows Gemini is turned in a contrary direction to the
others, judged that she marks the tropic, or conversion
of the sun, and that this zodiac thus agrees with the
planisphere.
By applying the idea of the easting (orientement) to
the small zodiac of Esne, we should find the solstices
between Gemini and Taurus, and between Scorpio and
Sagittarius. They would be even

(1) See the dissertation of the Abbe Dominique Testa. "Sopra due
Zodiaci novellamente scoperte nell' Egitto." Rome,
1802, p. 34.

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marked by the change of direction of Taurus, and by
the winged Rams placed across in these two places. In
the great zodiac of the same city, the marks would be
the position across of the Bull and the reverse situation
of Sagittarius. There would then only be one portion
of the constellation elapsed between the dates of Esne,
and those of Dendera, a space however still too long
for edifices so similar in construction.
The late M. Delambre appeared to confirm these
conjectures concerning their more modern construction
by an experiment on the circular planisphere; for on
placing the stars upon Hipparchus's projection,
according to the theory of this astronomer, and the
positions which he had assigned them in his catalogue,
increasing all the longitudes that thus the solstice
would pass through the second of Gemini, he nearly
reproduced this planisphere; and he says "this
similarity would have been still more close if he had
adopted the longitudes which are laid down in the
catalogue of Ptolemæus, for the year of our era one
hundred and twenty-three. On the contrary, on
referring back twenty-five or twenty-six centuries, the
right ascensions and declinations will be greatly
changed, and the projections will have taken an
entirely different figure.(1) All these calculations,"
adds the great astronomer, "lead us to the conclusion,
that the sculptures are subsequent to the epoch of
Alexander."
In fact, the circular planisphere having been brought
to Paris, by MM. Saunier and Lelorrain, M.

(1) Delambre. Note at the end of the report of the
Memoir of M. de Paravey. This report is printed in the
new Annals of Voyages, v viii.