Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions.Mercator was best known for his revolutionary world map 1569 and his great Atlas Sive Cosmographiae (1585).

This is a reproduction from our original map from Gerhard Mercator’s version of Ptolemaic maps Orbis antiqvi tabvlae geographicae secundum Cl. Taprobana, the name given to present day Sri Lanka and sometimes to Sumatra, was map XII. There are twelve maps of Asia, and maps X, XI, and XII cover parts of what is modern day India. The Ptolemaic atlases that were created based upon his writings were arranged in a consistent order based upon the textual arrangement and descriptions of Geography. No maps of Ptolemy’s exist and it is uncertain whether he actually made any. in tabulis occurrentium, situm, nomina recentiora, & alia eò pertinentia, lineis per ipsas ductis, accuratissime indicante in vsvm geographiae veteris stvdiosorvm (Asiae XII), 1730 Ptolemaevm, cum indice philologico absolutissimo omnium locorum, montium, fluminum, &c. Orbis antiqvi tabvlae geographicae secundum Cl. Geography was translated into Arabic and used by the North African born Arab al-Idrisi as a source for his famous map of 1159.

In his Geography he describes a world map and twenty-six regional maps of Europe, western and southern Asia, and northern Africa. The Geography of another Alexandrian geographer Claudius Ptolemy (90-168 A.D.) is the most well-known early work on geography. A reconstruction of his world map does show the Indus River. Eratosthenes (275-194 BCE), the Greek geographer and Chief Librarian of the Library of Alexandria who accurately calculated the Earth’s circumference, is said to have gained extensive knowledge of India, but no maps showing his knowledge are known to exist. A Japanese map done in an earlier traditional style in 1709 shows the 7th century trek of the Buddhist pilgrim Xuanzang in India. Some Chinese travelers went to India in search of information about the Buddha and understood the basic geography of India by at least the 2nd century, BCE. Given India’s ancient and advanced mathematical knowledge which allowed for relatively accurate calculations of the Earth’s circumference, and their use of latitude and longitude, it is likely that indigenous mapping did exist prior to European contact.

The Geography by Ptolemy