Zheng He's fleet succeeded to pull off all the three round voyages to the west sound and safe with each trip bringing back great news of all the neighboring countries showering praises on the Ming Dynasty. Having had the pleasant taste of carrying out peaceful foreign policy via oceangoing voyage, Emperor Yongle was resolved to further spread the prestige of the Ming Dynasty and to extend the dynasty's political clout. On November 15 of the tenth year during the reign of Emperor Yongle (December 18, 1412), the court issued an edict to Zheng He asking him to carry out a larger and farther voyage.

　　In December of the tenth year during the reign of Emperor Yongle (in 1413), Zheng He's fleet set off for the crossing-the-Indian-Ocean voyage. Champa was again made the first stop, and there the fleet had a brief stay. Then they passed Java, the Old Port, Melaka, Aru, Sumatra and Ceylon (now Sri Lanka) before reaching Calcut (now Kozhikode). They had a shot rest there to get their provision replenished. From there the fleet sailed off straight forward to Hormuz (now Bandar Abbas at the entrance of the Persian Gulf).

　　Zheng He's fleet didn't only confine the exploitation of new techniques to navigation in terms of observing the altitude of the stars and the measurement of distance, but also successfully put compass to serve the mapping out of the navigation plan and the guiding of the course of the fleet, which symbolizes that Zheng He's oceangoing voyage had gone beyond the stage of navigation by mere experience and had advanced to a new stage of complex navigation by integrating the knowledge of nautical astronomy with that of geography.

　　On the "Zheng He Nautical Chart" drawn by Zheng He himself, more than 530 place names in Asian and African waters were marked, of which over 300 were foreign place names. On the chart, not only cities, islands, navigation symbols, beaches, reefs and mountains were marked, but also the bearing and corresponding courses of the striking navigation landmarks along the coast were plotted, hence becoming the earliest, the most accurate and the most complete intercontinental nautical chart in the world, and for that matter, a great pioneering masterpiece in the world history of nautical surveying. Thanks to the availability of the navigation equipment and technologies that were necessary for long-distance voyage, Zheng He's fleet could safely and soundly complete the oceangoing voyage time and time again, thus accomplishing a miracle in the world navigation history.

　　This time the fleet returned to the homeland on July 8 of the thirteenth year during the reign of Emperor Yongle (on August 12, 1415). The voyage lasted twenty-one months, updating the record of duration and distance of Zheng He's voyages.

　　By Lu Rude

　　(PLA Daily)