A Comparative Study of the Astronomical Navigation Between Ancient China and Pacific Austronesian

Abstract

Astronomical navigation was a kind of sea route orientating and steering practice the ancient seamen used to judge the direction, relative position, and track of ships in the blue water of deep sea by observing the stars, other celestial bodies, and their regular occurrence in the sky, as one of maritime piloting methods employed by ancient Chinese navigators. The comparative study of ethno-archaeology revealed that the representative astronomical navigation practices recorded in the ancient Chinese literatures are highly consistent with the “star observation method” and “star measuring method” used by both the local seamen in south China and the Austronesian navigators in Pacific, showing the close cultural connection between them.

Astronomical navigation was a kind of sea route orientating and steering practice the ancient seamen used to judge the direction, relative position, and track of ships in the blue water of deep sea by observing the stars, other celestial bodies, and their regular occurrence in the sky, as one of maritime piloting methods employed by ancient Chinese navigators. The comparative study of ethno-archaeology revealed that the representative astronomical navigation practices recorded in the ancient Chinese literatures are highly consistent with the “star observation method” and “star measuring method” used by both the local seamen in south coast of China and the Austronesian navigators in Pacific, showing the close cultural connection between them.

1 A Brief Summary of the Steering Methods in Ancient Chinese Navigation

According to various books and charts of sea route orientation, there were three different kinds of steering methods in ancient Chinese navigation, the near shore terrestrially geographical guiding navigation, offshore astronomical navigation, and magnetic compass navigation. All of them roughly matured and synchronically developed in the navigation practice as early as in the Song and Yuan dynasties.

In the Vol. two of “Jia Ling (甲令)” of the “Record of Pingzhou Table Talk”

(Pingzhou Ketan 萍洲可谈) of the Song Dynasty, Zhu Yu (朱彧) said: “The boatmen sail on the sea and guide the vessel by reference of geographical sights of land, observing the stars at night and the sun in the day, or relying on the compass in the cloudy days” (Zhu, Y. 1985: 18). His words concluded three different kinds of boat guiding methods of “geographical sights reference”, “stars observing method” and “relying magnetic compass” in ancient navigation of China. In addition, Xu Jing (徐兢) wrote in the Vol. thirty-four of “Reef on the offshore Ocean (半洋焦)” of his Illustrated Record of an Embassy to Koryo in the Xuanhe Reign (Xuanhe Fengshi Gaoli Tujing 宣和奉使高丽图经) of the Song Dynasty, “At night the boat’s position in the ocean could not be tracked by the terrestrially geographical sights, so it could only be steered by observing the stars in the sky. In the cloudy days, the boat could be piloted by floating compass for direction” (Xu, J. 1985: 120). In his preface of Records of Countries in the Western Oceans (Xiyang Fanguozhi 西洋番国志), Gong Zhen (巩珍) wrote: “The boatmen have to observe the rising and setting of the sun and moon to track the direction of the navigation, to measure the height of stars above the horizon to reckon the position of the boat, to make a magnetic floating compass signed the ‘Ten Heavenly Stems gan (干) and Twelve Terrestrial Branches zhi (支)’ indicating the direction of the voyage” (Gong, Z. 1961: 5). Both of them recorded the usage of “observing stars” and the “magnetic compass directing” in ancient navigation, besides method of the geographical sighting.

The terrestrially geographical guiding navigation is to determine the position of the boat by referencing the geographical sights along the coast, such as mountains, river estuaries, reefs and tower buildings, and so on, which is logically the most primitive and fundamental steering method for navigation in human history. In ancient China, most of the waterway orientation books described these geographical sights along the nearshore sea routes in the chapter of “Landscape Sights of Mountain and Water (山形水势)” as the guides for navigation. Six sections in Sea Routes with Successful Sailing (Sunfeng Xiangsong 顺风相送) marked the features of mountains and the depth of waters, sands, and rocks composition of the seabed, and The Guide for Right Sea Routes (Zhinan Zhengfa 指南正法) included eight sections such as the “landscape sights of mountain and water along the sea route of Eastern Ocean” and the “landscape sights of mountain and water along the sea route from north Taiwu (太武) mountain to Guangdong.” The ninety-six illustrations in the Ancient Nautical Charts (Gu Hanghaitu 古航海图) marked the important landscape features of mountain and river estuary along the route from Liaodong (辽东) bay in Bohai (渤海) Sea to estuary of Pearl River. The Charts of Zheng He’s Voyages (Zhenghe Hanghaitu 郑和航海图) drew the sketches of the important mountains, reefs, river estuaries, castles, and temples along a more than 20,000 km nearshore sea route from empire shipyard Baochuan Chang (宝船厂) in Nanjing of lower reach of Yangtze River to Mombasa in East Africa, which was the most important terrestrially geographical guiding navigation chart of ancient China (Xiang, D. 1961, 1981; Zhang, Xun 1980).

The magnetic compass navigation relies on the marine magnetic device which always pointing to the north and indicating the direction of the voyage. After the invention and application of magnetic compass during Song and Yuan dynasties it became an accurate instrument for measuring the direction of the voyage of an offshore boat. The ancient seamen summed up the navigating experiences of long-term voyages, including the origin seaports, destination directions of the sea route (the position of the compass needle), and distances (counted by sailing time along the specific directions) between them of the different voyages, forming a series of “Nautical Compass Orientation” (指南针经) as the core content of the ancient sea route orientation books and charts. All of the nautical orientation books in Ancient China include various “Boatmen’s Waterways Book”, “Boatmen’s Secret Waterways”, “Compass Navigation Book” and “Compass Needle Navigation Book”, as recorded “all boatmen who navigate to different oceans respectively have their own orientation secret books…which are briefly called Yang Geng (洋更, meaning Oceanic Compass Navigation)” (Huang, S.J. 1936: 13). For instance, there are ninety-nine sections of magnetic compass needle routes including the one from Fujian to Cochin (Jiaozhi 交趾) of North Vietnam in Sea Routes with Successful Sailing, and fifty-five compass needle routes in the Guide for Right Sea Routes, covering the sea routes from mainland southeast China to Eastern Ocean, Western Ocean, Southern Ocean islands, Japan, and Ryukyu (Xiang, D. 1961: 49–99, 152–195). Taking example of the “compass needle route from Fujian to Cochin”, the route from Wuhumen (五虎门, Five Tigers) gate in Fuzhou to the destination seaport at Jichangmen (鸡唱门, Cock Crowing) gate in Vietnam was accurately arranged fourteen sailing courses (directions) including Yi Chen (乙辰), Bing Wu (丙午), Jia Yi (甲乙), Ding Wu (丁午), Kun Wei (坤未), Kun Shen (坤申), single Shen (单申), Kun Shen (坤申), Kun Wei (坤未), single Kun (坤), single Shen (申), Geng Shen (庚申), single Hai (亥), Qian Hai (乾亥) successively changed along the voyage, respectively corresponding different length of time gengs (更, 1 geng of ancient Chinese time unit equals 2 hours) during each course (Xiang, D. 1961: 51–52). Besides the terrestrial guiding navigation sights as previously talked in Charts of Zheng He’s Voyages and The Ancient Navigation Charts, there were also compass navigation guiding covering the directions of the magnetic needle and the length of time, such as the segment of “the boat set sail from Taicang (太仓) port with single Yi (乙) needle taking 1 geng to get Wusongjiang (吴淞江) port” and “from Baoshan (宝山) port with Xin You (辛酉) needle taking 3 gengs back via Wusongjiang port and dock to Taicang port”, quite accurately recorded the compass needle guiding routes along the tens of thousands of kilometers voyage forward to East Africa and back to Taicang port across the east and south China Sea and Indian ocean.

The premise of astronomical navigation is to observe and know well the constant and regular bearing of the stars and constellations in the sky, which can be the reference for seamen in the open sea to determine relative position of the boat and its voyage direction by measuring the angle or rising height of the specific star or celestial body above the horizon. From the Zhou and Han to the Ming and Qing dynasties, the Chinese historical books had kept the continuous records of astronomical navigation practice in the seas surrounding China. In addition to previous quoted Record of Pingzhou Table Talk, Illustrated Record of an Embassy to Koryo in the Xuanhe Reign, and Records of Countries in the Western Oceans respectively written in the Song and Ming dynasties, in which the three steering methods of terrestrial, astronomical, and magnetic compass were recorded, The Book of the Prince of Huainan (Huinan Zhi 淮南子) also recorded that “a boatman is easily lost and confused in open sea, but he will know the position of the boat oriented on the Polaris” (Liu, A. et al. 2010: 171). The section of “Outer Writing (外篇)” of the Book of the Master Baopu (Baopu Zhi 抱朴子) said that “those who were lost in a great lake should employ the magnetic compass while those in the open sea should orient on the Polaris to get the way back home” (Ge, H. et al. 2018: 816). All of these records indicate the importance of the sun, moon, stars, and constellations in the sky for the navigation steering in ancient China. It can be seen that ancient boatmen of China have mastered the method of astronomical navigation since Han and Jin dynasties, far earlier than the technique of marine magnetic compass.

2 The Astronomical Navigation Practice of Star Orientation and Course Steering in Ancient China

From monk Faxian’s (法显) experience on the sea, the “navigating by observing the sun, moon and stars” in South China Sea in the Eastern Jin Dynasty, to the “orienting on stars across the ocean (过洋牵星)” along the sailing of Zhenghe’s fleet, we can see the development of astronomical navigations of both “observing stars” and “measuring stars” in ancient China.

The ancient Chinese books of sea route orientation, such as the Sea Routes with Successful Sailing, Guide for Right Sea Routes and Charts of Zheng He’s Voyages and so on, records two types of astronomical steering methods of blue water navigation, the “star-observing orientation” and “star measuring orientation”. Among them, “star-observing orientation” is the basic while “star measuring orientation” is the key for course steering. On the one hand, because of nearly constant relative positions of distant stars and constellations in the sky associating with the earth’s rotation, most of the stars including the sun accurately rise in the east of the earth in the morning and set in the west, by which the boatmen guide the direction of navigation and get the star-observing orientation for direction. On the other hand, because of the earth’s rotation axis respectively pointing to the North Star (Polaris) and South Star (Antarctica), the relative positions of these stars above the south and northern poles are not affected by the rotation of the earth and appear to be almost motionless above the horizon at a specific location on earth, therefore The Guide for Right Sea Routes says that “the North Star and zenith stars sit motionlessly” (Xiang, D. 1961: 126). But these stars above the south and northern poles are respectively seen at different heights upon the horizon at different latitudes, just on the sea level at equator and the higher above the horizon at a higher latitude location, which is regarded as the most important clues for navigators to accurately estimate the latitude position of the boat and get the method of star measuring orientation for the navigation. So the North Star (Polaris) and South Star (Antarctica), not only can locate the north-south direction, but also the heights of them above the horizon can respectively show the different latitude position of the boat, and is what ascertained in Records of Countries in the Western Oceans as “reckoning the position of the boat by measuring the height of stars above the horizon” (Gong, Z. 1961: 5).

2.1 Observing Stars for Direction: “Navigating by Observing the Sun, Moon, and Stars”

There are a series of records about the open sea navigation methods for steering direction of the boat, including the “observing stars”, “surveying the positions of the rising and setting of sun or moon”, “observing the sun bearing”, “observing the moon bearing”, “observing the length of the day and night”, and the changing of these bearings in different the seasons, in Sea Routes with Successful Sailing and The Guide for Right Sea Routes (Xiang, D. 1961: 28–30, 110–112). Among these methods, the nine constellations or star clusters of the Big Dipper (Beidou 北斗), Cassiopeia (Huagai 华盖), South Cross (Denglonggu 灯笼骨), Aquarius (Shuiping 水平), Aries (Liangshang 凉伞), Vega (Zhinu 织女), Altair (Niulang 牛郎), Little Dipper (Xiaobeidou 小北斗) and Sagittarius (Nangdou 南斗), were listed with images of their appearance and positions of their rising/setting in Chinese coordinates “compass” with 24 scales signed Ten Heavenly Stems (天干) and Twelve Terrestrial Branches (地支) (Fig. 8.1).

Fig. 8.1

The star rising-setting compass in ancient Chinese navigation

The “Star-Observing Orientation” surveyed and defined the position of the rising and setting of different stars, providing boatmen alternative stars with different heights in sky as the reference for judging the direction of the boat sailing. In addition to the constellations of Altair (Niulang 牛郎) and Vega (Zhinu 织女), the stars’ rising/setting positions are distributed in two groups respectively above the North and South Pole. There are three constellations of Cassiopeia (Huagai 华盖), Big Dipper (Beidou 北斗), Little Dipper (Xiaobeidou 小北斗) in the sky of north pole, and four stars of Sagittarius (Nangdou 南斗), South Cross (Denglonggu 灯笼骨), Aquarius (Shuipin 水平) and Aries (Liangshang 凉伞) in the sky of south pole. For example, the section of “Star-Observing Orientation” in Sea Routes with Successful Sailing said: “The Big Dipper rises at Kui (癸) Chou (丑) in the northeast and sets at Ren (壬) Hai (亥) in the northwest. The Cassiopeia rises at Kui (癸) in the northeast and sets at Ren (壬) in northwest. The South Cross and Aquarius rise at Bing (丙) Ji (己) in the southeast and set at Ding (丁) Wei (未) in the southwest” (Xiang, D. 1961: 28). Except for their heights above horizon, their rising and setting points in the vast ocean above either side of the equator are fixed, providing a permanent reference for the orientation of east and west, north and south of the boat.

The methods of “surveying the position of the sun and the moon rising and setting”, “observing the sun bearing”, “observing the moon bearing”, “observing the length of the day and night” fix the changes of the rising and setting position of the sun and moon in the four seasons of the year. The Guide for Right Sea Routes even listed the locations of the rising and setting of the sun and moon month by month, providing a detailed basis for determining the direction of the boat in the open sea (Xiang, D. 1961: 110–111).

However, star-observing orientation is the basis of astronomical navigation, which can only assist in judging the course direction of sailing, rather than provide the determination or estimation of the specific location of the boat in the blue water ocean.

In 411 AD, the eminent monk Faxian of the Jin Dynasty returned to China from India by boat. The Biography of Monk Faxian records this journey “returning home by floating on the sea” and “navigating by observing the sun, moon and stars” which consisted of two segments of voyages:

The first voyage was in the Indian Ocean from the “The Lion kingdom Simhalauipa (师子国, now Sri Lanka) to Yavadvipa (耶婆提, now Sumatra)”, during which “The sea was vast and boundless without terrestrial guiding for direction and only way was to navigate by observing the sun, moon, and stars. When it was cloudy and raining the ship floated with the waves losing direction guiding. When the day was dark we saw billows only…and regain the direction until the sunny day…we sailed ninety days to reach the kingdom of Yavadvipa.”

The second voyage was in the China Sea from Yavadvipa to Changguang (长广) Prefecture of Shandong Peninsula, during this course he was onboard a big merchant ship with more than two hundred passengers. He brought with him the food enough for about fifty days which was normally taken for sailing to Guangzhou. Unfortunately, the boat lost the way and the journey was delayed because of bad weather, so they had to spend more than seventy days to get to Changguang Prefecture (Zhang, Xun 1985: 167–171).

In the vast and boundless Indian Ocean without terrestrial sights for guiding directions, Faxian’s boat obviously relied on the astronomical method of “navigating by observing the sun, moon and stars”, while during the voyage from Sumatra to China they went off course for the bad weather and losing the stars observing orientation. However, the basic method of star-observing orientation used in Faxian’s voyage from the Indian Ocean to the South China Sea was as an example of successful practice of astronomical navigation in early history of China.

So far, in the modern maritime ethnography along the coasts of Zhejiang, Fujian, and Hainan, the practice of stars observing orientation was still in use to guide the direction of the sailing, which is the cultural heritage of historical astronomical navigation. In Ningbo (宁波), Zhoushan (舟山), Wenzhou (温州) of Zhejiang Province there are proverbs of “observing the sun bearing” and observing the moon to fix the direction of the voyage. Zhoushan boatmen also guided the course direction of voyage by observing the rising/setting of the Venus (金星) that following the sun and called it “morning star” (启明星) and “night star” (长庚星). Fishermen along the coast of Fujian and Hainan have proverbs for remembering the seasonal variant of the rising/setting positions of the sun and the moon, such as the Hainan’s proverbs “the sun rises in summer at Jia (甲) of east and sets at Xin (辛) of west, rises in winter at Yi (乙) of east and sets at Geng (庚) of west, rises in spring and autumn at Mao (卯) of east and You (酉) of west” (Liu, N.W. et al. 1984: 8–11). This seasonal variant of star bearing orientation is consistent with the method of observing the sun, moon, and stars for orientation recorded in the Guide for Right Sea Routes.

2.2 Star Measuring Orientation: From “Measuring the Height of Stars” to “Orienting on Stars Across the Ocean”

The method of “star measuring” in navigation has been mentioned sporadically in ancient Chinese literature since the Han and Jin dynasties. The Book of the Prince of Huai’nan records “A boatman is easily lost and confused in open sea, but he will know the position of the boat oriented on the Polaris” (Liu, A. et al. 2010), which means estimating the position of the sailing boat by watching the Polaris Star in the north of the equator. Judging from this depiction, it is infered that  the ancient navigators of China knew how to define the boat position by measuring the height of the Polaris above the horizon. The Book of the Master Baopu also mentions that “those who were lost in the great lake should employ the magnetic compass, while those in the open sea should orient on the Polaris to get the way back home” (Ge, H. et al. 2018: 816).

Except the method of stars observing orientation discussed previously, the series books of sea route guiding, such as Sea Routes with Successful Sailing, The Guide for Right Sea Routes, Charts of Zheng He’s Voyages, General Survey on the East and West Oceans (东西洋考) and Records of Countries in the Western Ocean, also record another astronomical navigation methods of “reckoning position of the boat by measuring the height of stars above horizon” (Gong, Z. 1961: 5) in different ways. The method of “star measuring orientation for position” is based on the method of stars observing orientation for direction, relying on measuring the height above horizon of the North Star and South Star to determine the latitude position of the sailing boats. China situates in the northern hemisphere therefore the ancient Chinese navigators mainly depended on the North Star (Polaris) for measuring its height above the horizon to get the boat latitude position (Fig. 8.2).

Fig. 8.2

The method of “Star Measuring Orientation” in ancient Chinese navigation (Ha, angular height of big dipper at location A; Hb, angular height of big dipper at location B)

In the Yuan Dynasty, the Italian traveler Marco Polo left Quanzhou southward for going back to Europe, then traveled from the coast of the Indochina, Java island in Southeast Asia, via Nicobar-Andaman island to the east African coast of the Indian Ocean. On his voyage from Java the Lesser in Southeast Asia to western India the navigators continuously observed and measured the height of the North Star above horizon as the coordinates for determining the ship’s position. In Marco Polo’s book, he mentioned six times of measuring the North Star heights on horizon respectively in Java the Lesser, Samara, Komari (now Cape Comorin) and Malabar (now Kerala) of south India, Guzzera (now Gujarat), and Cambay (now Kambai) of west India. These places are distributed from Java island in the south of the equator to Cambay of western India near the Tropic of Cancer, roughly from southeast to northwest, where the heights of Polaris above horizon reflected the difference of latitude position of the ship, which was also the first practice of stars measuring orientation with definite quantitative facts related to the navigation history of East Asia (Table 8.1).

Table 8.1 The angular height above horizon marking the coordinates of latitude and longitude of Marco Polo voyage from Java to Cambay (Kambai)

The voyage of Zheng He’s fleet sailing to the West Ocean organized by the empire office of early Ming Dynasty was a feat in the navigation history of the world. Zheng He’s navigation condensed the various achievements of nautical technology in the past dynasties, combining near shore terrestrial guiding, magnetic compass, and astronomical orientation. According to Charts of Zheng He’s Voyages, during a number of segments of voyage from the island of Longxianyu (龙涎屿 now Pulau Breueh) in northwest Sumatra to Cape Guardafui (葛儿得风) of Somalia in east Africa, and the voyage along the west coast of India peninsula, a compound method of near shore terrestrial guiding, magnetic compass, and star measuring positioning was employed. Among them, “Orienting on Stars across the Ocean (过洋牵星)” had been the classic practice of the astronomical “star measuring orientation” in the navigation history of East Asia. The so-called “orienting on stars” was that the navigators “searched” and “defined” the Big Dipper (North Star 北斗星), Cassiopeia (Huagai 华盖星) and other stars over the south and northern poles, and measured their height above horizon in unit of finger zhi (指) and angle jiao (角, 1 jiao equals to a quarter of zhi) to mark the different latitude positions of the boat along the voyage.

Along the long voyage in the main course from Longxianyu (龙狿屿, now Pulau Breueh) island in West Sumatra to the west via Ceylon (锡兰, now Sri Lanka) and Calicut (古里, now Kozhikode in south of India) to Hulumosi (忽鲁谟斯, now Hormuz in Iran) and Aden (阿丹) in West Asia, then to Manbasa (慢八撒, now Mombasa of Kenya) and Malindi (麻林地) in East Africa, Zheng He’s fleet oriented thirty-two astronomical coordinates of islands, reefs and coastal places and respectively measured star heights above the horizon from East to West as following : Yilongliu (已龙溜, now southeast of Sri Lanka) oriented Cassiopeia with five zhis and two jiaos, Shachiliu (沙刺溜, now Suvadiva of Maldives) oriented Cassiopeia with six zhis and one jiao, Guanyu (官屿, now Male of Maldivian) oriented Cassiopeia with seven zhis and two jiaos, Jiapingnianliu (加平年溜, now one of Maldivian islands) oriented Big Dipper with one zhis, Anduliliu (安都里溜, now one of Maldivian islands) oriented Big Dipper with four zhis, Cochin of India oriented Big Dipper with three zhis, Calicut (卡利卡特, now Kozhikode) of India oriented Big Dipper with four zhis, Hahaweidie (哈哈迭微, now the north point of Calicut of India) oriented Big Dipper with four zhis and one jiaos, Xieli (歇立, now another north point of Calicut of India) oriented Big Dipper with four zhis and two jiaos to the North Star, Manggenuer (莽葛奴儿, now Mangalore of India oriented Big Dipper with s five zhis, Azhediao (阿者刁, now another point in Mangalore of India) oriented Big Dipper with six zhis, Chandawuer (缠打兀儿, now the other point in Mangalore of India) oriented Big Dipper with six zhis and two jiaos, Poerya (破儿牙, now a point between Mangalore and Cambay of India) oriented Big Dipper with six zhis, Boerya (跛儿牙, now another point between Mangalore and Cambay of India) oriented Big Dipper with eight zhis, Qierweier (起儿未儿 now another point between Mangalore and Cambay of India) oriented Big Dipper with eight zhis, Mahayin (马哈音, now another point between Mangalore and Khambhat of India) oriented Big Dipper with nine zhis, Malou (麻楼, now a point in south Khambhat in India) oriented Big Dipper with ten zhis, Kanbayecheng (坎八叶城, now another point in south Khambhat in India) oriented Big Dipper with twelve zhis, Keshi (客实, now Karachi of Pakistan) oriented Big Dipper with thirteen zhis, Mashiji (麻实吉, now Muscat of Oman) oriented Big Dipper with twelve zhis, Dawan (大湾, now a point of Dhofar port in Oman) oriented Big Dipper with nine zhis and two jiaos, Ahuna (阿胡那, now another point of Dhofar port in Omen) oriented Big Dipper with nine zhis, Zufar (佐法尔, now Dhofarin Oman) oriented Big Dipper with eight zhis, Luofa (罗法, now the west of Dhofar in Oman) oriented Big Dipper with seven zhis, Shilier (失里儿, now the west of Dhofar of Oman) oriented Big Dipper with six zhis, Aden of Yemen oriented Big Dipper with five zhis, Muerlihabier (木儿立哈必儿, now one point of northeast of Somalia) oriented Big Dipper with four zhis, Heier (黑儿, now another point of northeastern Somalia) oriented Big Dipper with three zhis and one jiaos, Mugudushu (木骨都束, now Mogadiscio of Somalia) oriented Big Dipper with two zhis and one jiaos, Muluwang (木鲁望, now a place in Somalia) oriented Cassiopeia with eight zhis, Manbasa (慢八撒, now Mombasa of Kenya) oriented Cassiopeia with seven zhis, Menfeidong (门肥东, now north of Malindi in Kenya) oriented Cassiopeia with seven zhis (Xiang, D. 1981: 54–62).

Besides, the Charts of Zheng He’s Voyages also records a few other astronomical coordinates with star-observing and measuring orientations along the branch segments of voyage in the Indian Ocean. The four illustrations of the “Orienting on Stars across the Ocean” in Zheng He’s charts are illustration of two round-trip courses of Calicut-Hulumosi and Sumatra-Ceylon, depicting graphically the types and heights s of the oriented stars above the horizon. Among them, the first and fourth illustrations are the round-trip courses between Calicut (古里, now Kozhikode in south India) and Hulumosi (忽鲁谟斯, now Hormuz in Iran). The first illustration is “orienting on stars across the ocean from Calicut to Hulumosi”, successively presenting from right to left, Calicut in the southeast via Dingdebaxi (丁得把昔, now Dandi Bandar in west India), Shamagushan (沙马姑山, now Jabal Sham mount in Oman) to Hulumosi in the northwest, with their different star orientations. Specifically, Calicut ellipsis (another illustration of the charts showed Calicut orienting Big Dipper with four zhis as quoted previously), sailing to Shamagushan by orienting Big Dipper with eleven zhis and South Cross with four and half zhis, at Dingdebaxi orienting Big Dipper with seven zhis and South Cross with eight and half zhis, at Shamagushan orienting South Cross with four and half zhis, sailing to Hulumosi by orienting Big Dipper with fourteen zhis. The fourth illustration is “orienting on stars across the ocean from Hulumosi to Calicut”, successively presenting from right to left, from Hulumosi in the northwest via Shamagushan, Dingdebaxi to Calicut in the southeast, with their different star orientations. Specifically, Hulumosi and Calicut ellipsis for being signed in first illustration, Shamagushan orienting Big Dipper with eleven zhis and South Cross with eight and half zhis, Dingdebaxi orienting Big Dipper with seven zhis. The third illustration is “orienting on stars across the ocean from Longxianyu (龙狿屿) to Ceylon”, and the second illustration is “orienting on stars across the ocean from Ceylon to Sumatra”, in which the sea route crossing a small range latitude, and Longxianyu orienting Big Dipper with one zhi and South Cross with fourteen zhis, Ceylon orienting Big Dipper with three zhis and South Cross with seven zhis (Xiang, D. 1981: 63–66).

In Sea Routes with Successful Sailing there are also four round-trip magnetic compass needle routes along which star measuring orientations were attached in Indian Ocean. On the needle route from Aceh (阿齐, now north of Sumatra) to Calicut of India, the boat orients Cassiopeia with eight zhis when leaving Mount Canaanmao (伽南貌山), and orients Cassiopeia with seven zhis and three jiaos when approaching Ceylon. On returning voyage from Ceylon, boat orients Cassiopeia with eight zhis. On the needle route from Calicut to Hulumosi, the boat orients Big Dipper with four zhis and South Cross with eleven and half zhis when leaving Calicut, orients Big Dipper with seven zhis and South Cross with seven and half zhis at Dingdebaxi, orients Big Dipper with four and a half zhis at Mount Meizhina (美之那山), when the boat approaching Hormuz orients Big Dipper with fourteen zhis and South Cross with one and half zhis. On the returning voyage, the boat orients both Big Dipper and Cassiopeia with twelve zhis and South Cross with four and half zhis at Mount Shaguma (沙姑马山, now Jabal Qurayyah in the United Arab Emirates), when it approaching Calicut the boat orients both Big Dipper with four zhis and South Cross with eleven zhis. On the needle route from Calicut to Aden, the boat orients Big Dipper with four zhis and South Cross with eleven and half zhis when setting sail from Calicut, orients Big Dipper with five zhis and South Cross with ten zhis and three Jiaos at Xixingyu (希星屿) Island, orients Big Dipper with five zhis and South Cross with ten zhis when passing Mount Zhijiaotanas (直焦塔那山), orients Big Dipper with five zhis and South Cross with ten and half zhis when arriving to Aden (阿丹). on the returning voyage, orients Big Dipper with five and half zhis and South Cross with ten zhis at Mount Tala (塔喇山). On the needle route from Calicut to Zufar, in Xixingshan (希星山) orients Big Dipper with five zhis and one jiao, and South Cross with ten zhis and one jiao at Mount Xixing (希星山), orients Big Dipper with six zhis and three jiaos and South Cross with eight zhis and three jiaos at Manjiaoshuanger (莽角双儿, now Mangalore in west of India), Big Dipper with seven zhis and three jiaos and South Cross with seven zhis san three jiaos when approaching to Zufar (祖法儿, now Dhofar in Oman), On the returning voyage, the boat orients Big Dipper with seven and half zhis and South Cross with eight zhis when setting sail from Zufar, and orients Big Dipper with five and half zhis and South Cross with ten zhis at Jiaotou (礁头) (Xiang, D. 1961: 78–81).

2.3 The Method of “Star Measuring Orientation” in Astronomical Navigation of Southeast of China

According to these practices of astronomical navigation centering in South China Sea and Indian Ocean recorded in ancient Chinese sea route orientation books, and the related archaeological and ethnographical discoveries, the methods of star measuring orientation were not completely same, but with variant techniques and tools to measure the  heights of stars, different units to show the height of the stars above the horizon, such as “centimeter” used by Marco Polo fleet and finger zhi (指) and angle jiao (角) in Zheng He’s fleet and other Chinese boatmen. But these star measuring orientation practices were intrinsically relevant and essentially unified.

The tool for measuring the height of stars corresponding to the method of “orienting on stars across the ocean” of Zheng He’s fleet was a kind of “Star-Orienting Board” (牵星板). Li  Xu (李诩) described the content of this measuring scale in chapter one “Zhoubi’s Ruler” (周髀算尺) of his Essays of the Old Man Hut (Jie’an Lao’ren Manbi 戒庵老人漫笔) in the Ming Dynasty, the “Star-Orienting Board” firstly shown by Ma Huaide (马怀德) in Suzhou (苏州), was made of a set of twelve pieces square board of hard wood with successive sizes of one finger zhi (指) up to twelve zhis, the largest piece of board with twelve zhis was about seven cuns (寸, 1 cun of length is about 3.3 cm). There was also a piece of square ivory board with four corners missing called Zhoubi’s Ruler (周髀算尺), which was two chi (尺, 1 chi of length is about 33.3 cm) long and successively signed half zhi, half angle jiao (角), one jiao and three jiaos (Li, X. 1982: 29).

Obviously, this pair of “Star-Orienting Board” consists of 12 grade-scaled plates with scales of 1–12 zhis respectively together with a square ivory plate of 1–4 jiaos. The four corners of the ivory plate were cut into varying lengths with a half jiao (1/8 zhi), one jiao (1/4 zhi), a half zhi (2 jiaos) and three jiaos (3/4 zhi) respectively to be the complement rule scale of the 12 large boards. When the navigator observed and measured the stars he used different scales of the boards according to varying heights of the stars. The navigator held a proper star-orienting board forward to make it erect and perpendicular to the sea surface, and make its lower end aligned to the tangent of the sea and sky. The oriented star appeared in the upper end of the board, then the corresponding scale zhis of the star-orienting board and the number of supplementary jiaos on the ivory plate (if required) was just the height of the celestial body above the horizon (Fig. 8.3).

Fig. 8.3

The “Star-Orienting Board” in ancient Chinese navigation

A bamboo ruler unearthed in the shipwreck of Song Dynasty at Houzhu (后渚) seaport of Quanzhou in Fujian Province in 1974 was recognized as another star measuring tool of navigation. This rule is 20.7 cm long, specially carved one scale at one end and four scales at the other end, with an interval space of about three scales between them, each scale is about 2.6 cm (QZMMFJ 1987: 22; Figs. 8.4 and 8.5). Professor Han Zhenhua (韩振华) held that it was a ruler to measure the height of stars for navigation in the Song Dynasty. The interval space of about three scales in the middle of the ruler was the holder for boatman or where the bracket or handle was installed. The length of the four scales corresponded to the four fingers (zhis) of “star measurement with bare palm” in maritime ethnographies of southeast China, and the actual length of the four scales (2.6 × 4) was about equal to that of the average human palm. When it was in use, the end of the four scales was upward, and the seaman extended his arm forward holding the lower end of the ruler under the first scale and aligning it with the tangent of the sea and the sky, then the position of the oriented star on the four scales was its height above horizon (Han, Z.H. 1980).

Fig. 8.4

A bamboo ruler as a star measuring tool in navigation from the shipwreck of Song Dynasty unearthed in Quanzhou, Fujian (after QZMMFJ 1987)

Fig. 8.5

Comparison of measurement of the angular height of star by the naked fingers of fisherman in Hainan and restored bamboo ruler from the shipwreck of Song Dynasty unearthed in Quanzhou

In the maritime ethnographies in the southeast coast of China, the fingers of hand have been the most important “tool” of boatmen to measure the height of the stars in sky. The star measuring orientation was also a popular method of course steering among the boatmen in Zhejiang, Fujian, Guangdong, Guangxi, and Hainan of southeastern coast of China, indicating the profound cultural foundation of astronomical navigation practice. The proverb among boatmen of Zhoushan (舟山) archipelago in Zhejiang says that “by knowing the Polaris stars one is able to travel around the world”, while the similar proverb of Beihai (北海) in Guangxi says that “those who know the Polaris stars are able to sail in five lakes and four seas over the world”. Both of them concisely revealed the importance of measuring the height of polar stars for their steering in navigation. The primitive method of “measuring the height of stars” used by boatmen in south of China was a kind of bare palm measurement. The fishermen in south island of Qinglan (清栏) of Wenchang (文昌) County in Hainan measured the height of the North Star (Big Dipper) above horizon with only five naked fingers (Fig. 8.5). They extended their right hands above sea level, expanding the palm with its center forward and the thumb downward, the end of the thumb was tangent to the sea-sky connection line and the little finger upward, then the observed corresponding positions of North Star on this palm rule such as the index finger, middle finger, ring finger, and little finger respectively indicated the heights of one zhi, two zhis (half palm), three zhis and four zhis (one palm) of the star above the horizon. Huang Huayin (黄华荫), a fisherman from Hainan island, measured the height of the North Star above the sea horizon near Hainan island as nearly one palm (four zhis), while he measured the height of the North Star on the sea horizon of the central Vietnam as half palm (two zhis). According to these practical surveying data of fisherman Huang Huayin, professor Han Zhenhua calculated that one zhi in star measurement orientation of modern fishermen of southeast coast of China were about 5° and 44 min in latitude, one palm and four zhis were 22° and 38 min. The height of the North Star over horizon around Hainan island is less than one palm and about 20° in latitude, while the height of North Star above horizon around central Vietnam is half palm and about 11° and 24 min in latitude, both of which are consistent with actual situation. This primitive method of star measurement with bare palm was an important inspiration for the study of the origin of ancient Chinese measuring ruler of the star height in navigation (Han, Z.H. 1980; Liu, N.W. et al. 1984: 11–13). Because the star measuring orientation originated from this primitive method of “star measurement with bare palm”, all ancient Chinese sea route orientation books used the unit of zhi (指, the finger) in recording the star height above horizon in astronomical navigation.

The ethnographical “star measurement with bare palm” in South China Sea reflects the original and early stage of star measuring orientation in navigation, which might be the logical predecessor of star measuring ruler recognized in Quanzhou shipwreck of Song Dynasty and Star-Orienting Board of Zheng He’s fleet of Ming Dynasty. These developed and evolved methods of star measuring orientation with rulers or scaled board were similar to that of modern fishers in Wenchang (文昌) County of Hainan, who just hold the vertical ruler to measure the height of star, making the lower end of the rule tangent to the sea surface so the upper end measures the height of stars. The method of stars measuring orientation included in the traditional compass needle navigation books in Jinghai (靖海) village of Hui’an (惠安) county of Fujian, was called the “method of measuring the height of star along the meridian”, for instance, “the height of star along the meridian in Luzon (吕宋) is measured as five cuns (寸, 1 cun equal to 3.33 cm) and six fens (分, 1 fen equal to 0.33 cm), in Biaowei (表尾) is measured as seven cuns and two fens, in Wuyu (浯屿) of southern Fujian is measured as one cun and seven fens” (Liu, N.W. et al. 1984: 12). Directly marking the height of stars above horizon with a ruler, in this case, might be the result of using a ruler or scale for measuring the height of stars in nautical orientation.

To sum up, the astronomical navigation in ancient southeast of China has developed from “navigating by observing the sun, moon and stars” to “orienting on stars across the ocean”, consisting of two categories of methods of “star-observing orientation for direction” and “star measuring orientation for position” with a long developing history. The measurement of height of the stars and constellations on horizon and searching the latitude position of the sailing boat provided reliable steering for offshore navigation before the appearance of magnetic compass in ancient China.

3 The Comparison of Astronomical Navigation Between South Coast of China and Pacific Austronesian

Before western navigators made their way into the Pacific Ocean, the indigenous Austronesian maintained an excellent technical system of navigation, including the unique seafaring crafts of double canoe and outrigger canoe, the changing triangular sails and sailing techniques of downwind and wardwind, as well as a series of marine geographical steering methods and astronomical orientation which were distinctive section in the world’s nautical history. Austronesian has been the genius ethnics of astronomical navigation, who developed peculiar star compass for direction reference and star measuring orientation for fixing position. During his first Pacific voyage from east to west in 1769, Captain James Cook was amazed to witness the extraordinary practices of native navigation, their methods of observing the sun, moon, current changing and wind direction for orienting their destination island, or measuring stars in the sky for accurately defining the position of sailing canoe. When Cook left Tahiti he took the indigenous navigator Tupaia along with him, and it was Tupaia, with his ability of identifying and measuring stars and constellations, steering directions, destining the islands and the excellent downwind sailing skills, brought the Cook’s fleet to New Zealand, Australia and Batavia (Haney, D. 1998: 40; Endeavour, P.A. 2001: 153, 169).

In the past half century, anthropologists had carried out in-depth investigations, researches, experiments, and restorations of the astronomical navigation of Austronesian (Sharp, A. 1957; Dodd, E. 1972; Lewis, D. 1994; Finney, B. 1994, 2003; Finney, B. et al. 2007). In 1964 and 1968, under the guidance of a number of native navigators from Melanesians who still retained the memories of traditional navigation methods, Davis Lewis successively sailed his boats of Rehu Moana and Isbjorn across the long distance ocean without compass and modern nautical gears, but naked-eye observation of stars, wind, and ocean current. Lewis’ experimental navigation among the islands of Oceania left us valuable knowledge and record of aboriginal seafaring of the Pacific, including astronomical orientation of star observation.

In 1958, Ben Finney from the Department of Anthropology at the University of Hawaii began exploring the traditional navigation of native Polynesians. In 1973, together with the famous navigator Tommy Holmes, he founded the Polynesian Voyaging Society, engaging in reviving the original sailing techniques of Polynesian composite canoes, and in 1976 he successfully sailed the double canoe Hokule’a from Hawaii to Tahiti island 2250 miles away. The captain of the voyage was a Hawaiian expert catamaran sailor Elia Kawika Kapahulehua, and the master navigator Pius Mau Piailug from a maritime family of Satawal Island of Caroline Islands of Micronesia who learned from his grandfather, his father, and uncle with rich knowledges of star orientation and oceanic hydrology, was recruited to pilot the sailing (Finney, B. 2003: 9–14).

As a new generation of master navigators of Hawaiian, Nainoa Thompson was also an important witness to the revival of traditional navigation methods of the Pacific, taking part in the 1976 voyage from Hawaii to Tahiti on Hokule’a and learning the traditional navigation knowledge of indigenous people from the old master navigator Pius Mau Piailug. In 1980 Nainoa sailed Hokule’a back from Hawaii to Tahiti in a non-instrument voyage. Since then Hokule’a had several successful Pacific voyages, and in 1995 Ben Finney organized six double canoes which included Hokule’a, sailed independently from Tahiti to Hawaii by using Nainoa’s navigation methods, resulting in the roughtly same courses of six double canoes, confirming the accuracy and effectiveness of the old navigation methods of the Pacific indigenous people (Finney, B. 2003: 110–130).

In general, the nautical skills of indigenous Austronesian were rich and complex, slightly varying in different islands and sea areas. The stars and constellations, wind and clouds, ocean currents and migratory birds, and so on, were all references for orienting direction and position in native navigation. Among them, star navigation was the most representative technology, which including two types, the Star Compass indicating the rising/setting positions of different stars in the sky for orienting the direction of the sailing boat, and the bare hand measuring of the height of polar stars above horizon to determine the latitude position of the sailing vessel.

The “Star Compass” of Satawal in Carolinian Islands of Micronesia was not a real compass instrument but an abstract image of horizon in navigators’ minds in which the stars and constellations bearing, which was called naang in Satawal language. This image of star compass arranged the rising/setting positions of the polar stars, 15 zenith constellations above horizon within a 32-scale circular or square plan. This star compass with Satawal island in its center acted as a giant coordinate system and reference for orienting the boat direction in the sea around Satawal Island for the native sailors (Fig. 8.6). Because the positions of rising/setting of stars and constellations are related to the changes of latitude, there were different Star Compass systems in different latitudes, for instance, the islanders of Woleai in Caroline islands and the new generation of Hawaiian navigator Nainoa Thompson all had their own Star Compass for navigation (Finney, B. et al. 2007).

Fig. 8.6

The “Star Compass” of native sailors in Satawal Island of Carolinian (after B. Finney, et al. 2007)

The Pacific indigenous navigators also noted the correlation between the height of the polar stars above horizon and latitude variations. Nainoa Thompson used bare fingers and hand to measure the height of Polaris above horizon and calculate the latitude’s position of the boat on the voyage from Hawaii to Tahiti. In his experience, the height of each finger above the horizon was equivalent to 2° of latitude, so the fingers could measure the Polaris to a total height of 10° of latitude. For example, extending the right arm, resting the lower middle finger on the horizon, index finger upward, then the latitude height of the middle point of the middle finger, the upper end of the middle finger, the middle point of the index finger, the upper end of the index finger respectively measured 1°, 2°, 3°, 4°. If using the five fingers of the entire palm to measure stars, rest the lower end of the small finger on the horizon, then the position of the upper thumb measured 10° latitude.

The entire hand with an open palm could also be used to measure the stars at greater latitude. Holding out entire hand, opening palm toward horizon with the downward thumb perpendicular to the index finger and the tip of the thumb was tangent to and rested on the horizon, then the junction of index finger and the end of middle finger roughly indicated between 12° and 23° (Fig. 8.7). Hawaii and Tahiti are located between the Tropics of Cancer and Capricorn on both sides of the equator, with a latitude distance of about 40°, and the height of Polaris and Antarctic Star above horizon had been respectively measured by hands of island navigators as the important astronomical orientation for positioning in seafaring (Finney, B. et al. 2007).

Fig. 8.7

The measurement of the angular height of star above the horizon by bare fingers in Austronesian navigation (after B. Finney, et al. 2007)

In addition to the above-discussed star observation and measurement orientation systems, they also have “Wind Compass” which relying on the seasonal and regular wind directional variations, “Swell and Current Piloting”, “Navigator Birds” and “Islands Charts Orientation”, reflecting the long-term practical experience of their navigations in the Pacific Ocean.

The cross-cultural comparison of ancient Chinese navigation, the boatmen ethnography of south coastal China, and the navigation cultures of the indigenous Austronesian, is not difficult to find a high degree of commonness of primitive astronomical navigation in the vast Asia–Pacific maritime regions.

The ancient astronomical navigation in the southeast coast of China included two types of star orientation by observation and measurement. The star observation focused on the seasonal variation of the rising/setting of the sun, moon, stars, and constellations as the direction reference for the sailing course steering. The star measurement focused on the height of North Star or Big Dipper above horizon in different sea regions to determine the latitude position of sailing boat. Interestingly, the astronomical techniques of the Pacific Austronesian comprised two almost identical categories, namely, the “Stars Compass” in different sea regions recording the rising/setting positions of the stars and constellations body as the reference for the direction of the sailing course, and Nainoa Thomson’s method of “Star Measuring” with hand and fingers to get the height of polar stars above horizon to estimate the latitude position of sailing canoe.

Regarding the operation techniques, the southeastern China and Pacific share a highly consistent operational method of astronomical orientations. The “Star Observation Orientation” recorded in the sea route guides of ancient China such as The Guide for Right Sea Routes mark the rising and setting positions of variant stars on the Chinese coordinates “compass” with 24 scales signed Ten Heavenly Stems gan (干) and Twelve Terrestrial Branches zhi (支), while the “Star Compass” of the Pacific islanders such as Satawal and Woleai in Caroline Islands and Nainoa Thompson’s also marked the rising and setting positions of stars on the 32-scale star compass. Moreover, as the reference for steering direction in navigation, both “Star Observation Orientation” in southeastern China and “Star Compass” in the Pacific were the image of horizon with star bearing in navigators’ mind rather than the real one as magnetic compass. The positioning orientation of “Star Measurement” with bare palm manifested in the maritime ethnography of southeastern coast of China was also very similar to Hawaiian navigator Nainoa Thompson’s hand and fingers’ measuring star height above the horizon.

It is thus clear that there probably had been an ancient astronomical navigation community or cultural interaction between the maritime societies in southeast China and the Pacific indigenous peoples. The “Star Compass” used to distinguish directions of the rising and setting of stars and the “Star Measurement” with bare palm used to get the height of stars and latitude position of a sailing boat are the common maritime cultural heritages of this navigation community. It is not difficult to understand the reasons for the existence of this navigation cultural community if we return to the perspective of the blueprint of ethno- history of the Bai Yue-Proto-Austronesian interaction (Wu, C.M. 2003).