Studies in the Geography of Ancient and Medieval India c26.21

c26.21

With reference to the knowledge of map-making among the people of India, especially the Dravidians of the South, the following remarks in the *Encyclopaedia Britannica* (14th ed., Vol. XIV, pp. 840-41) are also interesting: "The charts in use by the medieval navigators of the Indian Ocean—Arabs, Persians or Drāviḍas—were equal in value, if not superior, to the charts of the Mediterranean. Marco Polo (thirteenth century) mentions such charts; Vasco da Gama (1498) found them in the hands of his Indian pilot, and their nature is fully explained in the *Mohit* or 'the Encyclopaedia of the Sea,' compiled from ancient sources by the Turkish admiral, Sidi 'Ali Ben Hosein, in 1584. These charts are covered with a close network of lines intersecting each other at right angles. The horizontal lines are parallels, depending upon the altitude of the Pole Star, the Calves of the Little Bear and the Barrow of the Great Bear above the horizon. This altitude was expressed in *isbas* or inches, each equivalent to 1° 42' 50''. Each *isba* was divided into *zams* or eighths. The intervals between two parallels thus only amounted to 12' 51''. These intervals were mistaken by the Portuguese occasionally for degrees, which accounts for Malacca, which is in Latitude 2' 13'' N., being placed in Cantino's chart (1502) in latitude 14' S. It may have been a map of this kind which accounts for Ptolemy's moderate exaggerations (in the second century A.D.) of the size of Taprobane (Ceylon). The first meridian, separating a leeward from a windward region, passed through Ras Kumhari (Comorin) and was thus nearly identical with the first meridian of the Indian astronomer, which passed through the sacred city of Ujjain (Ozéné of Ptolemy) or the meridian of Azīn of the Arabs. Additional meridians were drawn at intervals of *zams*, supposed to be equal to three hour's sail."