The Shelves · Mathematics (incl. astronomy)

Handy Tables and the Canobic Inscription

Known · Attestedin Alexandria?Conjectured · Our reconstructionour placementLegend · Told storya told story on its tag

I · The entry, in his form

In the table of Mathematics (incl. astronomy)

Conjectured · Our reconstructionour placement

c. 100–170 CE. Made his observations at Alexandria between 127 and 141 CE and set up the Canobic Inscription in 146/147. The Almagest gave astronomy its form until Copernicus and the Tetrabiblos did the same for astrology; he also wrote the Geography, the Handy Tables, the Harmonics and the Optics.

Handy Tables and the Canobic Inscription

Opening words not preserved.

Length: not counted

Above, his entry form, filled from what we know. Below, ours.

II · Does it survive? Where to read it

Survives in large part

The Handy Tables survive in Theon of Alexandria's edition; the Canobic Inscription's text survives in manuscripts.

Was it in Alexandria?

Known · Attested

Written in Alexandria.

On the table: written in Alexandria; no evidence it was in the Library.

Read it today

The Canobic Inscription is edited and discussed in Jones (2005).

III · In the show

Astrology · Chronology: Ptolemy's TetrabiblosPtolemy's Tetrabiblos, c. 150.Known: attested
Astrology · Figures: Claudius Ptolemy; Vettius Valens; Dorotheus; FirmicusKnown: attested
Astrology · The working parts of a chart, with the Ptolemaic aspects auditedKnown: attested

+ 16 more

Fixed StarsSets Agrippa's star natures beside Ptolemy's (Tetrabiblos I.9) and says where they differ.Known: attested
Zodiacal HoursCites Ptolemy, Almagest II, for the seasonal hours.Known: attested
Planetary HoursThe Chaldean order Ptolemy also uses; Cassius Dio (37.18–19) credits the planetary week to the Egyptians.Known: attested
The Thema Mundi and Planetary Rulerships, episode 36, at 49 secondsTranscriptThe Thema Mundi and planetary rulerships (station 2 of Astrology and Cosmic Order).Known: probable
Chaldean Order, Luminaries, and Planetary Houses, episode 36, at 7 minutes 14 secondsTranscriptThe Chaldean order, the luminaries and the planetary houses.Known: probable
Priest-Astronomers & Early Astrology, episode 20, at 14 minutes 11 secondsTranscriptPriest-astronomers and early astrology (station 1 of Astrology and Cosmic Order).Known: probable
Theurgic Astrology & Natal Charts, episode 22, at 58 minutes 44 secondsTranscriptTheurgic astrology.Known: probable
The Thema Mundi and Planetary Rulerships, episode 36, at 1 minute 28 secondsTranscript“much like Vidius Valins and those early kind of Greco Roman Egyptian”'Vidius Valins' is Vettius Valens, whose Anthology leans on Egyptian authorities.Known: probable
Hellenistic Roots of Western Esotericism, episode 24, at 1 hour 4 minutes 40 secondsTranscript“his book, Henistic Astrology, I think came out in 2017”Chris Brennan, Hellenistic Astrology (2017).Known: probable
Path: Astrology and Cosmic Order, station 1Start with the priest-astronomers.Known: probable
Path: Astrology and Cosmic Order, station 2Draw the birth chart of the world.Known: probable
Path: Astrology and Cosmic Order, station 5Use the chart as a map.Known: probable
Astrology · Chronology: The Hellenistic synthesisThe Hellenistic synthesis.Known: probable
Western Esotericism · The Map of the Current: Hellenistic astrology in Greco-Roman EgyptKnown: probable
Decan Calculator'Egyptian in origin… Hellenistic and later Arabic astrology absorbed the scheme.'Known: probable
Planetary Day'The seven-day week of planetary days is Hellenistic'; Cassius Dio 37.18–19.Known: probable

IV · Sources and the living entry

Ancient references (2)

Canobic Inscription (ed. Heiberg, Opera astronomica minora, 1907)
Olympiodorus, Commentary on the Phaedo (Ptolemy at Canopus)

Modern scholarship (3)

A. Jones, 'Ptolemy's Canobic Inscription and Heliodorus' Observation Reports', SCIAMVS 6 (2005): 53-98.
A. Tihon, Le 'Petit Commentaire' de Theon d'Alexandrie aux Tables Faciles de Ptolemee (Vatican City: Biblioteca Apostolica Vaticana, 1978).
O. Neugebauer, A History of Ancient Mathematical Astronomy, 3 vols (Berlin: Springer, 1975).

Entry checked 31 Oct 2026 · no corrections · Suggest a correction ›

HANDY TABLES AND THE CANOBIC INSCRIPTION

Read what is told

The back of the tag: a story told of this work, in its teller's voice.

Legend

Forty years at Canopus

Olympiodorus tells, some four centuries later, that Ptolemy lived forty years at Canopus, in the temple's precinct.

Told by Olympiodorus, 6th century CE, some four centuries later

What the evidence supports

Ptolemy set up his parameters on a stele at Canopus in 146/147 CE, and its text survives. The forty years are a late tradition.

Sources (2)

Olympiodorus, Commentary on the Phaedo
Canobic Inscription ed. Heiberg 1907

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