From the third year of Yongle in the Ming Dynasty (1405) to the eighth year of Xuande (1433), the great Chinese navigator Zheng He led a huge fleet of ships to the Western Ocean seven times and visited more than 30 countries along the coasts of Southeast Asia and the Indian Ocean, which not only set up a monument for mankind to understand the ocean and conquer the ocean, but also wrote a brilliant chapter for enhancing the friendship between the Chinese and African people and the exchange of Chinese and foreign cultures and materials, but also developed maritime navigation and positioning technology, and drew the world-famous "Zheng He Navigation Chart", which made great contributions to the development of marine surveying and mapping.
Zheng He (1371–1433), a native of Kunyang (present-day Puning County), Yunnan, was a Hui ethnic group. The original surname is Ma, the name and the word Sanbao (三保). At the age of 12, he entered the palace as a waiter and was later given to Zhu Di, the King of Yan. In July of the first year of Jianwen (1399), Zhu Di raised an army to "Jingnan", and because of the merits of the Three Treasures in the incident, he was promoted to the eunuch of the Inner Palace, and was given the surname Zheng, also known as the "Three Treasures Eunuch".
In June of the third year of Ming Chengzu Yongle (1405), the emperor ordered Zheng He and Wang Jinghong to send envoys to the West. Its purpose is recorded in the "Biography of Ming Shi Zheng He": "Cheng zu suspected that Emperor Hui had died overseas, wanted to trace it, and wanted to show the wealth and strength of China." Between the third year of Yongle and the eighth year of Xuande (1405-1433), Zheng He led a huge fleet of ships to the Western Ocean seven times, passing through the South China Sea Zhudao to reach the Western countries.
The first voyage to the West: Yongle 3rd year (1405) june 15th edict, the same year of winter sailing, Yongle 5th year (1407) ended on September 2, passing through Champa City, Siam, Mansaka, Old Port, Sumatra, Ceylon, Guri, Namburi and other countries and regions.
The second voyage to the West: Yongle 5th year (1407) september 13th edict, late winter sailing, Yongle 7th year (1409) ended in late summer, passing through Champa City, Siam, Hunli, Guawa, Mansika, Ceylon, Gayel, Kochi, Guri, Namburi and other countries and regions.
The third voyage to the West: Yongle 7th year (1409) september 28th edict, December sailing, Yongle 9th year (1411) June 16th end, passing through Champa City, Siam, Hunli, Guawa, Mansika, Aru, Sumatra Thorn, Ceylon, Gambali, Little Gülen, Kochi, Guri, Gayle, Namuli and other countries and regions.
The fourth voyage to the West: yongle decade (1412) november 15th edict, Yongle eleventh year (1413) march voyage, Yongle thirteenth year (1415) july 8, passing through Champa City, Pahang, Guawa, Mansaka, Aru, Kelantan, Ceylon, Kezhi, Guri, Lysan, Chushan, Khurumus, Mukudushu, Namburi and other countries and regions.
The fifth voyage to the West: Yongle Fourteenth Year (1416) December 10th Edict, Yongle Fifteenth Year (1417) Winter Sailing, Yongle Seventeenth Year (1419) Ended in July, passing through Champa City, Guawa, Huani, Pahang, Manjiga, Ceylon, Shaliwan Mud, Kezhi, Guri, Mubone Dushu, Bu Thorn Wa, Adam, Thorns, Khurumus, Malin, Lyom Mountain, Sumatran Thorn, Nam wu li and other countries and regions.
The sixth voyage to the West: Yongle was edicted on January 13, 1421, set sail in the spring of the same year, and ended on August 18, the twentieth year of Yongle (1422), passing through Champa City, Forced Luo, Manjinga, Pungge Thorn, Ceylon, Kezhi, Chushan, Guri, Zufar, Adam, Thorn Sa, Mu Bone Du Shu, Bu Thorn Wa, Kurumus and other countries and regions.
The seventh voyage to the West: Xuande 5th year (1430) June 9th edict, Xuande 6th year (1431) December 9th sailing, Xuande 8th year (1433) July 6th ended, passing through Champa City, Siam, Guawa, Mansaka, Sumatra Thorn, Pungg Thorn, Ceylon, Little Glange, Gajel, Kezhi, Slippery Mountain, Guri, Khurumus, Afar, Adam, Thorns, Tianfang, Mukudushu, Bu ThornWa, Bamboo Step, Aru, Gambari, Nam Boli and other countries and regions.
Zheng He's nautical chart was originally called "Zibao Shipyard Driving Ship from Longjiang Pass to Foreign ZhufanTu", which was referred to as "Zheng He Nautical Chart" by later generations according to custom. The map is a record of Zheng He's voyage to the West, dating from about the first year of Hong Xi (1425) to the fifth year of Xuande (1430). The original picture is a hand-scrolled style unfolded from right to left, and Mao Yuanyi was included in the "Wu Bi Zhi" volume 240 and then changed to the book style, a total of 24 pages, including Mao Yuanyi's preface page, figure 20 pages, "Cross-Ocean Star Map" two pages (four pictures), blank page.
Zheng He's nautical charts are the earliest surviving nautical atlases in the world, and they are also important materials for studying Zheng He's voyage to the West. The specific production time of this map is unknown, but it is said that after Zheng He's sixth voyage to the West, all the officers and men who went to the west were garrisoning Nanjing. At that time, when Emperor Xuanzong Zhu Zhanji was contemplating going to the Western Ocean again, coupled with the long suspension time and the time to organize, he comprehensively sorted out the successive voyages of Zheng He's fleet to the Western Ocean and drew a complete map of the Western Ocean, which was a work collectively compiled for the Zheng He mission to meet the needs of the Western Ocean. However, there are also views that the route depicted in the map coincides with the route of Zheng He's main fleet in the seventh voyage to the West, and may be a work after the seventh voyage to the West, but the drawing should not be later than the middle of the 15th century.
The basic route depicted on the map starts from Nanjing, descends along the river, goes south along the coast after going to sea, crosses the Strait of Malacca along the coast of the Indochina Peninsula and the Malay Peninsula, and passes through the Ceylon Mountains (present-day Sri Lanka) to the Slippery Mountain Country (present-day Maldives). This was divided into two routes, one crossing the Indian Ocean to the east coast of Africa and the other crossing Arabia from the Slippery Mountains to Kurumus. The objects of mountains, islands, bridges, temples, cities and other objects in the picture are drawn in the form of traditional Chinese landscape painting three-dimensional scene writing, and the image is intuitive and easy to identify during navigation. For major countries and states, counties, health, institutes, patrol divisions, etc., they are marked with boxes to show their importance. There are more than 530 names depicted on the map, including the coasts of Asia and Africa and more than 30 countries and regions. There are more than 50 round-trip routes, and the navigation and positioning data such as needle paths and more numbers marked next to the routes are more practical. This fully shows that at that time, China's sea vessels had a lot of experience in long-distance voyages, and the level of navigation technology had reached a fairly perfect level.
3. Highlighting the elements related to navigation, the chart is a sea chart of the writing scene, and it belongs to the needle map system, which is dedicated to navigation, so it itself highlights the characteristics of the nautical chart. The content elements represented in this diagram are all for the needs of navigation. The first is to highlight the needle path (heading) and the number (voyage) of the voyage; the second is to locate and navigate the needs, the salient targets are drawn into a pair of scenes, so as to facilitate identification and positioning. The third is to use text to explain the location of the steering point and the number of water depths for bathymetry and positioning, as well as to indicate the leading star data. These are the basic elements that guarantee safe navigation.
2. Different picture frames reflect different navigation needs. For example, a section of navigation from Nanjing to Taicang is an inland river voyage, which needs to constantly change the course along the river, so the map does not indicate the needle path and the number. Since it is mainly based on the positioning and navigation of the objects on both sides of the strait, the terrain and features on both sides of the strait are depicted in particular detail on the map. Another example is the east and west coasts from Taicang to Sumatra to the Indian Peninsula, mainly coastal and offshore navigation, in addition to using compass navigation, and with mountains and islands as the target, so the map is painted with significant peaks and features, and the main routes are noted with needle positions and more instructions to ensure the safety of navigation. The route from The Slippery Mountains to Kurumus, because it is an ocean voyage, the map plate not only indicates the basic needle path, but also adds the lead star data to facilitate the use of astronomical navigation.
3, the map frame configuration to the route as the center of the "Zheng He Navigation Chart" on the direction is not the above north down south drawn, but highlight the main route, the entire route is from right to left continuous, because the original direction of these lines is different, so the direction of the map frame is also different. For example, the Nanjing to Taicang route was originally from west to east, and the map is painted from right to left, and the map width orientation becomes right west left east, up south and north; for example, the route along the mainland coast after the mouth of the Yangtze River is basically from north to south, but the route on the map is still drawn from right to left, so the map width orientation becomes right north, left south, up west and down east. The navigation chart drawn in this way, although the orientation of the map is not uniform, is convenient for use in navigation.
Zheng He led a huge fleet of ships to the West seven times, and the size of its formation, the breadth of the measurement area, and the high level of technology were unique in the world at that time. The navigation and surveying and mapping personnel of Zheng He's fleet inherited and developed the surveying and mapping techniques of their predecessors, and the nautical charts and transoceanic star map surveyed and mapped during the voyage were the earliest and best nautical atlases in the world at that time, and the number of positioning means and the high accuracy of them were also beyond the reach of Western countries. It can be seen that Zheng He's western ocean and nautical charts have made great contributions to the development of oceanographic surveying and mapping, which has made China's hydrographic surveying and mapping reach the peak of the world.
Marine surveying and mapping data have been accumulated. Zheng He's fleet of ships in the West was grand in scale, and each voyage led more than 200 large and small sea vessels equipped with supplies, cargo, warships and other types, with more than 27,800 personnel, using monsoons and hydrometeorological laws to travel far into the ocean formation, which was unique in the world at that time. During the voyage, the course and voyage of many routes were determined, and many reefs, shoals and mountains and water potential were measured in and around the main channel. On the Zheng He Navigation Chart, the Irregular Large Circle and Small Circle represent The Shixing Stone Pond (i.e., the Zhongsha Islands) is used to distinguish it from the shallow sand represented by the small circle, which is the earliest record found to determine the nature of the Zhongsha Islands, and the earliest legend representing the underwater reef beach. Zheng He's fleet also carried out small team activities abroad, surveyed many new routes, and obtained many surveying and mapping materials. In the northern Indian Ocean and at important locations along the coast, the altitude of the star effluent was also determined, contributing to the safety of navigation and the accumulation of mapping data.
Maritime positioning technology has been developed. When Zheng He went to the Western Ocean, he comprehensively used methods such as transoceanic star pull, land landmark to view, estimation of voyage, measurement of water depth and other methods to determine the ship position, which improved the accuracy of maritime positioning, not only inherited the maritime positioning orientation method of previous generations, but also developed the maritime navigation and positioning technology. Transoceanic star-related navigation, that is, astronomical navigation at sea, is an astronomical navigation method that guides ships across vast seas by observing the height of the antenna of the star (mainly the North Star) from the water to determine the change of the geographical location of the ship from north to south. "Zheng He Navigation Chart" attached to the ocean led star map 4, the middle of each is a long box, its orientation is up and north down south, left west right east, the box is painted a sailing ship sailing on the sea, outside the frame according to the rough direction is painted with stars for the stars, marked with star names, indices, some stars and straight lines connected to the frame edge, may be the stars involved at that time, the right side of the rectangular box has the name of the map and text description, the content is basically the same as the note on the frame edge. The four transoceanic mappings specify the transoceanic mapping data of the two routes between Sumatran and Ceylon Hill, Guri and Kurumus. The most commonly used North Star (α Ursa Minor in the Ming Dynasty), the North Star, is the most used because of its water height and haunting time, which are not affected by the seasons. There are also canopy stars, often used β Ursa Minor, γ, and the North Star cannot be seen when sailing near the equator and the southern hemisphere, and the canopy star is used instead. According to the land target to determine the ship position, is the ancient coastal navigation commonly used method, zheng he nautical chart from Nanjing to Taicang section is not noted needle road, but the two sides of the route can be located for the contour of the object marker made a schematic representation, the full map shows the most detailed section, followed by the southeast coast of China, the purpose is to judge the ship position according to the significant object mark and the shape of the mountain. Zheng He's fleet also used a combination of needle positions (mileage traveled) and the use of methods such as water depth and substrate to calculate (judge) the ship position.
Innovative mapping methods. Ancient charts were mostly drawn and used in combination with "figures" and "sutras (or zhi)". Before Zheng He went to the Western Ocean, although there were sea traffic maps, overseas domain maps, sea route maps, sea route guide maps, etc., they all needed to be used in navigation according to text instructions. Judging from the "Guide Map of Sea Roads" left over from the Yuan Dynasty, there are only shorelines, river estuaries, place names and island names on the map, which are not obviously different from ancient maps. In addition to the main content of the map, the "Zheng He Navigation Chart" sets navigation data such as needle position, more number, water depth, star data, navigation precautions and other navigation data on one map, which is clear at a glance, although there is distortion in scale and orientation, but there is no need to use pictures and text, and you can sail with the map. Undoubtedly, this is an innovation in the history of ancient Chinese mapping.
It has exercised territorial sovereignty over the South China Sea Zhudao Islands. The South China Sea Zhudao has been China's territory since ancient times. When Zheng He led a huge fleet of ships to the Western Ocean, he passed through the South China Sea Zhudao and sent envoys to Western countries. In the fifth year of Xuande (1430), Zheng He's navigation chart during his seventh voyage to the West included the South China Sea islands in the map of China. On the "Zheng He Navigation Chart", the names and relative locations of "Shixing Shitang", "Shitang" and "Wansheng ShitangYu" are clearly marked, that is, the present-day Zhongsha, Xisha and Nansha Islands. In the 36th year of the Republic of China (1947), in order to commemorate the activities of Zheng He's fleet on the South China Sea Zhudao when they sailed the Western Ocean, the Chinese government named the island group on the west side of the Paracel Islands as the Yongle Islands and the island group on the east side as the Xuande Islands; the names of Zheng He and his entourage, as well as Shi Jinqing, Liang Daoming, Yang Xin, etc., also appeared in the names of some islands and reefs in the South China Sea, such as Zheng He Reefs, Yin Qing Reefs, Fei Xin Island, Ma Huan Island, Jinqing Island, Daoming Reefs, Yangxin Sandbar, etc. In April 1983, the Chinese government published some of the standard place names for the South China Sea Zhudao, retaining these names associated with Zheng He's fleet.