Agathodaemon of Alexandria
Agathodaemon of Alexandria (Greek: Ἀγαθοδαίμων Ἀλεξανδρεὺς, Agathodaímōn Alexandreùs) was a Greek or Hellenized cartographer, presumably from Alexandria, Egypt, in late Antiquity, probably in the 2nd century A.D.
The line appears in the running text of the Geography and not as a caption on the maps themselves. Since the inscriptions are the only surviving reference to him and these manuscripts only survive from the very late 13th century, the most that can be stated conclusively is that he lived sometime between the years AD 150 and 1300, although his classical name and his epithet—"the Alexandrian"—probably places him before that city's fall to the Caliphate in 641 and not contemporary with Maximus Planudes's reconstruction of the Ptolemaic atlas after 1295.
In the Geography, Ptolemy shows his familiarity with existing maps, complaining of the inaccuracies introduced by cartographers to Marinus of Tyre's work through his failure to provide proper accompanying data, a fault Ptolemy remedied by providing sample captions in his own books VII and VIII. In those sections, he explicitly mentions that his text was to be accompanied by maps constructed according to his principles. Heeren argued for Agathodaemon having been the cartographer responsible for these original maps; Dinse for his having been the transcriber of the original papyrus scrolls to codices; and Fischer for a strictly literal reading of the inscription, showing that differences in the early manuscripts imply Agathodaemon drafted the world map but not the regional maps.
A major consideration is that the current form of Ptolemy's regional maps are done according to Marinus's cylindrical projection—which Ptolemy disparages—rather than either of Ptolemy's; the world map is done according to the less-favored of the two projections Ptolemy offers.
- Claudius Ptolemy
- The Geography
- Ptolemy's world map
- The Canopic Branch of the Nile Delta, called the Agathodaemon by Ptolemy
- Other Agathodaemons
- Berggren, J. Lennart; et al. (2000), "Introduction" (PDF), Ptolemy's Geography: An Annotated Translation of the Theoretical Chapters, Princeton: Princeton University Press.
- Brown, Lloyd Arnold (1979), The Story of Maps, Mineola: Dover, ISBN 9780486238739.
- Dinse, Paul (1913), "Die handschriftlichen Ptolemäus-Karten und die Agathodämonfrage [The Handwritten Ptolemy-Map and the Agathodaemon Question]", Zeitschrift der Gesellschaft für Erdunde zu Berlin, Berlin, pp. 745–770. (in German)
- Fischer, Josef (1914), "Zur Ptolemäusforschung", Petermanns Mitteilungen [On Ptolemaic Research], p. 287. (in German)
- Heeren, A.H.L. (1827) [Originally published in Com. Soc. Gott., Vol. VI, in 1823], Commentatio de Fontibus Geographicorum Ptolemaei Tabularumque iis Annexarum; Num ii Graecae an Vero Tyriae Originis Fuerint? [Commentary on the Origin of Ptolemy's Geographical Works and Their Appended Maps, Whether They Were Truly of Greek or Tyrian Origin], Göttingen: Dieterich. (in Latin)
- Long, George (1842), "Agathodæmon", The Biographical Dictionary of the Society for the Diffusion of Useful Knowledge, I, Pt. II, London: Longman, Brown, Green, & Longmans, p. 443.
- Mason, Charles Peter (1867), "Agathodaemon (2)", in Smith, William (ed.), Dictionary of Greek and Roman Biography and Mythology, I, Boston, p. 65.
- Ptolemy (c. 150) [Translated 1994], Γεωγραφικὴ Ὑφήγησις [Geōgraphikḕ Hyphḗgēsis, "The Geographical Guidance"], translated by Louis Francis as Ptolemy's Geographia, University of Oxford Text Archive.