The Oldest Anonymous Scholia on Ptolemy’s Geography (original) (raw)

Of paths and places: the origin of Ptolemy's Geography

In his Geography, Ptolemy recorded the geographical coordinates of more than 6,300 toponyms of the known oikoumenē. This study presents the type of geographical information that was used by Ptolemy as well as the methods he applied to derive his geographical coordinates. A new methodological approach was developed in order to analyse the characteristic deviations (displacement vectors) of Ptolemy's data from their reconstructed reference locations. The clusters of displacement vectors establish that Ptolemy did not obtain his coordinates from astronomical observations at each geographical location. The characteristic displacement vectors reveal how Ptolemy derived the coordinates: (1) he constructed locations on maps using a compass and ruler, for which he employed a small amount of astronomical reference data and geographical distance information; (2) he made schematic drawings of coastlines, based on textual descriptions of coastal formations; (3) and he situated additional locations within the established framework using reports of travel itineraries.

Ptolemy's Geography in Byzantium

English translation of the article, Η Πτολεμαϊκή Γεωγραφία στο Βυζάντιο. Pages 1-6 are also examined in detail in my article, Maximos Planoudes and the “Diagram” of Ptolemy. The 47verse poem of Planoudes, Praise to Polemy, is translated in English for the first time and commented analytically (pp. 7-12). The 14th c. scholars and their cartographical contribution are examined for the first time, too.

The Reliability of Ptolemy's Toponyms and the Identification G

N.A., 2024

The basis of this paper is a manuscript dated 1405, dedicated to the future antipope Alexander V (1409-10). Its main purpose is to give a summary update to researchers of cartography and geography, utilizing new results of the best scholars. Between c. 127 and 148 CE, Claudius Ptolemy collected and published a list containing 6,300+ points defined by “longitudes” and latitudes. A short paper with a table cannot be complete but condensed. It does not attempt to transform or beautify any of the so-called “Ptolemy maps”. Each identified entry compares Ptolemy’s longitudes and latitudes with their modern equivalents, assigning them a “longitudinal reliability factor.” This is complete through the introduction of a preliminary zero meridian placed at –14°, to the west of Greenwich, and a simple formula to facilitate conversions. The long table with the identified reference points creates a reliable numerical database instead of the subjective visual approach. Numerous locations are associated with ancient astronomical traditions or observations, through clusters of towns all over Europe, Asia, and Africa. The aim was not to illustrate the problems but solve them numerically.

“Some Notes on the Tradition of the Diagrams (and Maps) in Ptolemy’s Geography”

Claudio Ptolomeo, Geografía (Capítulos teóricos), ed./transl. R. Ceceña (Mexico City: Facultad de Filosofía y Letras, Universidad Nacional Autónoma de México), 2018

(Introductive Chapter: Graphicacy and Reproduction) The careful study of diagrams in illustrated manuscript texts can be extremely illuminating: it not only contributes, of course, to a better understanding of a certain text, but also sheds light on the history and the tradition of the text in question as well as on the history of the manuscripts containing and handing down this text, and hence on the stemmatology of these manuscripts. Nevertheless, the close reading of diagrams in illustrated manuscript texts has long been neglected. This aspect of analyzing a text and its tradition has only recently become popular among scholars. Ptolemy’s Geography is a productive study subject for this method. The chapters on map projections in the theoretical parts of this work are provided with a set of originally five diagrams: four diagrams in Geogr. I,24 and one diagram in Geogr. VII,6. They are meant to illustrate the complex instructions on how to draw the three projection methods suggested by Ptolemy for tracing a world map or, more precisely, a map of the oikoumene: of the inhabited parts of the world then-known. In the extant Greek manuscripts of Ptolemy’s Geography these diagrams appear intercalated into the text and can be found in both textual recensions of the work, Ξ and Ω. In some manuscripts, the diagrams –either all of them, some of them, or only one of them– were omitted. In this case the scribes often left a blank space (a so-called fenestra) between the two text portions where the diagram was supposed to have been placed. Thus the insertion of the diagrams was usually also planned in Geography codices which are completely or partially lacking the diagrams. All these circumstances suggest that the diagrams go back to an old tradition: they were most probably an integral part of the work since its composition ca. 150 CE, although the oldest surviving witnesses of Ptolemy’s Geography date from around the turn of the 13th to the 14th century and were therefore copied far more than one thousand years later. The diagrams in the manuscripts of Ptolemy’s Geography are generally corrupted and defective in various ways: they were obviously continually copied from their respective models. As my examinations showed, they were usually drawn by the scribes, who ordinarily were not trained in cartography, in technical drawing, or in fundamental science; they roughly reproduced what they found in their exemplar, without necessarily understanding it. We can therefore argue that the distortion of the diagrams in the manuscripts is on the one hand due to a) a lack of graphicacy of the persons who drafted the diagrams. Lack of graphicacy may have also been a reason for leaving them out. On the other hand the deformation of the diagrams is as a result of b) continuous reproduction, i.e. copying.