Sailing Charts
See also: Chinese geography and Chinese directionsZheng He's sailing charts were published in a book entitled the Wubei Zhi (A Treatise on Armament Technology) written in 1621 and published in 1628 but traced back to Zheng He's and earlier voyages. It was originally a strip map 20.5 cm by 560 cm that could be rolled up, but was divided into 40 pages which vary in scale from 7 miles/inch in the Nanjing area to 215 miles/inch in parts of the African coast.
There is little attempt to provide an accurate 2-D representation; instead the sailing instructions are given using a 24-point compass system with a Chinese symbol for each point, together with a sailing time or distance, which takes account of the local currents and winds. Sometimes depth soundings are also provided. It also shows bays, estuaries, capes and islands, ports and mountains along the coast, important landmarks such as pagodas and temples, and shoal rocks. Of 300 named places outside China, more than 80% can be confidently located. There are also fifty observations of stellar altitude.
Read more about this topic: Zheng He
Famous quotes containing the words sailing and/or charts:
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He spoke with Turk and Jew
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For all tongues he knew.
O whats a wifeless man? said he
And he came sailing home.”
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