Haidaojing 海道經

Haidaojing 海道經 "Manual of sailing directions" is a book on navigation written during the Ming periody 明 (1368-1644) by an unknown person, whose personal name was Ju 璚, while the family name in known. The book was compiled later than 1411. The reason for writing the book is laid out in the preface, stating that the transport of tribute grain over the sea, caused by the breakdown of the Grand Canal, was a difficult matter, and required guidance.

The book was reprinted multiple times after its completion. In the edition published by Yuan Shengyang 袁生陽, two texts of inscriptions were appended, one on official regulations (zeli 則例) and another on sacrificial offerings. Later, when Cang Tingsheng 藏亭生 reprinted the work, he also included two essays related to maritime transport from Liu Renben's 劉仁本 Yuting ji 羽亭集 at the end of the book.

The Haidaojing documents maritime routes, oceanographic and meteorological knowledge, and emergency measures at sea from the Yuan dynasty 元 (1279-1368) through the early Ming period. It explains the preparation for emergencies, sea routes, sea route navigation charts, observing the sky, the clouds, the sun, rainbows, fog, lightnings, the sea, the ties, and Northern Sea Regions. Two introductory essays discussing maritime transport during the Yuan period and the dangers of the Yangtze River.

The text is included in the series Jieyue Shanfang huichao 借月山房彙鈔, Zeguzhai chongchao 澤古齋重鈔 and Congshu jicheng chubian 叢書集成初編.