home articles forum events
glossary horary quiz consultations links more

Read this before using the forum
View memberlist
View/edit your user profile
Log in to check your private messages
Log in
Recent additions:
The Life & Work of Vettius Valens
by Deborah Houlding
Can assassinations be prevented? by Elsbeth Ebertin
translated by Jenn Zahrt PhD
A Guide to Interpreting The Great American Eclipse
by Wade Caves
The Astrology of Depression
by Judith Hill
Understanding the zodiac: and why there really ARE 12 signs of the zodiac, not 13
by Deborah Houlding

Skyscript Astrology Forum

Ptolemy on Weather

Post new topic   Reply to topic    Forum Index -> Traditional (& Ancient) Techniques
View previous topic :: View next topic  
Author Message

Joined: 28 Mar 2020
Posts: 682

Posted: Tue Aug 31, 2021 6:03 pm    Post subject: Ptolemy on Weather Reply with quote

Deborah Houlding offers us a translation of Ptolemy's Centiloquium from Henry Coley's 17th century translation here

Her practical and useful approach help us understand the 100 sentences of Ptolemy

On the website (an E-book site created by Patricia Eberlin on various subjects including a section on astrology) the translation of Nicolas Bourdin of the Centiloquium is followed by a presentation of 2 texts of Ptolemy.
1. Appearances of fixed stars and announcements translated by Halma
2. Memoir on Ptolemy's Calendar by M. Ideler

These are these 2 texts following the translation of the Centiloquium that caught my attention. The first one under the title “Inerrantium stellarum apparitiones, ac significationum collectio.” (Free translation: The apparitions of the fixed stars and the collection of meanings). The second one is a Memoir on Ptolemy's Calendar by M. Ideler. You can read the full text on

“It is a calendar such as the Greeks had many under the name of Parapegms, or collections of star rises and sets, in the twilight both in the evening and in the morning, which were so many visible announcements of the seasons, with prognoses of the stars. main temperature changes, relative to each climate, based on observations from the best meteorologists. What particularly distinguishes it from all older calendars is that it does not give appearances of entire constellations or groups of stars, of the constellation of Delphinus, for example, or the Hydra, or Centaurus, etc. ; but only simple stars, first and second magnitude, not according to the partly uncertain observations of early astronomers; but, in general, arranged according to the calculations of its author.”
“Ptolemy, to make his Parapegm useful to all the Greeks in the world of his time, did not give the appearances of the stars only for a parallel, but for five of them; for the five where the longest day of the year is 1:30 p.m., 2:30 p.m., 3 p.m. and 3:30 p.m. He himself teaches us, in the sixth chapter of the second book of his great Treatise on Astronomy, and in the introduction to it, what is the situation of these five parallels.
    The first passes through Syene, under a pole height of 23 degrees 51 ’;
    the second, through Lower Egypt, under 30 degrees 22 ’;
    the third, by Rhodes, under 36 degrees;
    the fourth, by the Hellespont, under 40 degrees 56 ’;
    the fifth, by the middle of the Pontic Sea, under 45 degrees 1 ’

; to distinguish them, he uses the same hourly numbers, which he uses only for the appearances of the Fixed Stars. The University of Oxford has a good quality manuscript of it, and much more exact with regard especially to the number of hours of the parallels.”

“The temperature announcements he gives almost every day are taken from the calendars of the Egyptians, Julius Caesar, and the most common among those of the Greeks, Meton, Euctemon, Democritus, Eudoxus, Conon, Dositheus, Metrodorus, Philippe , Callippe and Hipparchus, whom he names everywhere as his guarantors. The announcement does not always relate to the Appearance of the Fixed Stars where it has stored it, on the same parallel; but only on each date, as we can see, in that it often gives, according to Callippus and Caesar, the temperature for an apparition which takes place below the 3 p.m. parallel, according to the Egyptians, and for another which belongs to the 3:30 p.m. parallel. A scholium which one reads at the end of the calendar, and which Petau attributes to Ptolemy, although it is expressly said there that it is not of the author of the Hemerologia, indicates the country in which the authors named of the Parapegme, mainly made their observations.”

Here are the stars he mentions below (Tropical position given on January 1, 2000 at 0h according to Astrotheme) namely:
1. Arcturus, (24 Lib 22)
2. Vega (15 Cap 27)
3. Capella (21 Gem 51)
4. Hyades (5 Gem 48')
5. Regulus (29 Leo 57)
6. Denebola (21 Vir 37)
7. Spica (23 Lib 58')
8. Betelgeuse (28 Gem 53)
9. Rigel (16 Gem 57)
10. Sirius (14 Can 12)
11. Procyon (25 Can 53)
12. Fomalhaut (3 Pis 59)
13. Achernar (15 Pis 27)
14. Canopus (14 Can 52)
15. Bungula (29 Sco 35)
16. Altair (1 Aqu 54)
17. Coronae Australis (6 Cap 33)
18. Deneb Adige (5 Pis 27)
19. Mirfak (2 Gem 05)
20. Alpheratz (14 Ari 18')
21. Capella (21 Gem 51)
22. Beaver (20 Can 14)
23. Pollux (23 Can 13)
24. Zuben Elgenubi (South 15 Sco 05)
25. Zuben Elschemali (North 19 Sco 22)
26. Antares (9 Sag 46)
27. Rukbat (16 Cap 38')
28. Rigel (16 Gem 50)
29. Alnilam (23 Gem 28')
30. Alphard (Alfard) (27 Leo 17)

For each of the stars,
True Heliacal rise: When the star and the Sun rise at the same time
Apparent Heliacal rise: When the star is seen to rise on the eastern horizon shortly before sunrise

True Acronical rise: When the star rises on the eastern horizon at sunset
Apparent Acronical rise: When the star rises on the eastern horizon shortly after sunset

True Heliacal setting: When the star sets on the western horizon at sunset
Apparent Heliacal setting: When the star sets on the western horizon shortly after sunset

True Acronical setting: When the star sets on the western horizon at sunrise
Apparent Acronical setting: When the star sets on the western horizon shortly before sunrise.

“Ptolemy records the four appearances, both for true rising and setting of a star, giving for each of the five parallels, twenty appearances, make six hundred for all thirty. There are eight for Canopus, and as many for a of the centaur, stars which are visible only under the three australis parallels; and four for the last of the River, which does not rise for the most northern parallel.”
(Note: For the record, I have separated the True and Apparent risings and settings of the Stars because they can show something different whether they are Oriental or Occidental to the Sun).

Ptolemy says:
“Because, we must have regard to the changes caused in the atmosphere by the various aspects of the planets, compared to the sun, as when the sun enters the solstices and the equinoxes, not that we want to cover all the causes, but to show that the moon and the five planets contribute the most; the moon, by reducing the announcements taken from the days of the apparitions, to those of its configurations with the sun; and the five planets by cooperating with the concomitant influences, in proportion to the forces and affinities of these particular bodies, as can be seen by the times of the seasons, sometimes simultaneous, sometimes delayed by the effect of the intervals of the syzygies of the sun and of the moon, and their qualities, most often, more or less affected by the competition of the planets.“...
“and finally, the qualities proper to the essence of that of the five planets which is in aspect with it, giving Venus warmth; at Saturn, the cold; to Jupiter, the wet; to Mars, the dry; and to Mercury the rainy wind; in which it is necessary to take account of their reciprocal reactions, to explain their annoyances.” And he makes good use of the Fixed Stars in his calendar.

For each of the 5 latitudes, he then goes on to describe... Example
“Thothou September
1. (According to us Romans August 29. At the fourteenth hour, rise the star from the lion's tail . According to Hipparchus, the summer winds are subsiding. Rains and thunders, according to Eudoxus.
2. At the fourteenth hour, the star of the lion's tail rises and the Epi hides, according to Hipparchus, announces....
3. At half past one, rises the lion's tail . At 3 p.m., rise of the star called the Goat. According to the Egyptians, the summer winds cease. Wind, rain, thunder, according to Eudoxus. According to Hipparchus, the wind from the equinoctial east is blowing.

“Each of these stars, in each of the parallels where they rise and set, showing itself each year under four appearances, it happens however that Canopus does not rise but only in three of these five parallels taken from the equator. From where the sum of all is 580, of which I described the announcements which I recorded in this pamphlet, according to the Egyptians, Dositheus, Philippe, Calippe, Euctémon, Méton, Conon, Métrodore, Eudoxe, César , Democritus and Hipparchus.”

In her book 'Astrometeorology' Kris Brandt Riske says that “Weather phenomena and their correlation to planetary configurations were undoubtedly some of the first mundane events observed and recorded by the ancients Babylonians as far back as the second millennium B.C.... It wasn't until 1686 that an entire volume in the English language was devoted to astrometeorology. In that year Dr. J. Goad's Astro-Meteorologica was published in London.”
It has been followed by other publications since then with the most popular being the annual 'Almanach' for weather and gardening.
While we use the Lunations, Eclipses, Solstices and Equinoxes to predict weather, it might be a good idea to look back at what Ptolemy was brewing in his Calendar with the Fixed Stars for they also influence the forecast.

Back to top
View user's profile Send private message
Martin Gansten

Joined: 05 Jul 2008
Posts: 1484
Location: Malm, Sweden

Posted: Wed Sep 01, 2021 2:56 pm    Post subject: Reply with quote

If we compare the Centiloquium with the Tetrabiblos, it is fairly obvious that they are not by the same author, so 'Pseudo-Ptolemy on Weather' might have been a better subject heading. Wink

Incidentally, it's acronychal, from ἀκρονυχία akro-nuchia 'beginning of the night, nightfall'.
Back to top
View user's profile Send private message Send e-mail

Joined: 28 Mar 2020
Posts: 682

Posted: Wed Sep 01, 2021 4:04 pm    Post subject: Reply with quote

A note in the text says that "we read at the end of the calendar, and which Pétau attributes to Ptolemy, whatever seed says that it is not from the author of the Calendar, indicates the country in which the named authors of the Parapegm, have mainly made their observations.".
I left it as Ptolemy since the manuscript had been published under his name.

Thanks for the precision on the term 'acronychal' Martin. I took it from the Matrix Astro Dictionary
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Forum Index -> Traditional (& Ancient) Techniques All times are GMT
Page 1 of 1

Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
. Powered by phpBB © 2001, 2005 phpBB Group

Contact Deborah Houlding  | terms and conditions  
All rights on all text and images reserved. Reproduction by any means is not permitted without the express
agreement of Deborah Houlding or in the case of articles by guest astrologers, the copyright owner indictated