People and Culture in Oceania, 35: 109-125, 2019 Communication A Report on the Reassessment of Navigation Stones on Arorae, Kiribati Akira Goto,* Hideyuki Ohnishi,** Tomo Ishimura*** 1. Introduction This report is a reassessment survey of “navigation stones” on Arorae Island, southern Kiribati. The survey was conducted by Akira Goto, Tomo Ishimura, and Hideyuki Ohnishi in August 2016. Kiribati (Gilbert Islands) lies on the southern border of Micronesia fringed with the Cook Islands, Samoan Islands (both belonging to Polynesia), and Fiji (Melanesia), and so the culture of Kiribati has been formed from the mixture of Micronesian traditions (e.g. Caroine Islands and Marshall Islands) with influences from these neighboring islands in the south and the east (Figure 1: left). The so-called “navigation stones” are a series of stones found on the northwestern tip of Arorae Island (Figure 1: right). H. E. Maude, who later became a famous historian, first became interested in these stones when he was working as a government officer in 1933. It was then that Figure 1. Left: Kiribati Right: Arorae Island (Red Circle Indicates the Researched Area) * School of Humanities, Nanzan University, Japan. [e-mail: [email protected]] ** Faculty of Contemporary Social Studies, Doshisha Women’s College for Liberal Arts, Japan. [e-mail: [email protected]] *** Tokyo Institute of Cultural Property, Japan. [e-mail: [email protected]] 110 A. Goto, H. Ohnishi, and T. Ishimura Figure 2. Area Where Navigation Stones Distribute on Northwestern Tip of Arorae he first made a rough sketch of these stones. Later, Captain E. V. Ward created a map showing the distribution of these stones, although his manuscript has never been published. D. Lewis, who is famous for his study of indigenous navigation in the Pacific, obtained Ward’s manuscript and analyzed the direction of these stones (Lewis, 1994: 363). In 1957, these stones were surveyed by Captain B. Hilder, who formally published his findings (Hilder, 1957) . Ward wrote that there are 13 stones, excluding one that is considered an “entrance stone,” but he posited that only 11 stones retained their original positions. In contrast, Hilder found 9 stones, including an entrance stone, and he created a map of these stones. Japanese archaeologists Takayama and Kaiyama surveyed these stones and reanalyzed these previous reports in the 1990s (Takayama and Kiyama , 1993). Unfortunately, Takayama and Kaiyama did not publish a revised map. When we examined these stones in 2016, we could identify 9 stones as Hilder described, although his description of the positions of the stones does not seem to be exact. We reassessed the positions and orientation of the stones using GPS (Figure 2). Before going into the details of our survey, we make a brief review of Kiribati starlore by examining information collected by Arthur Grinble and compiled by his daughter R. Grimble (Grimble, R., 1 972). Navigation Stones on Arorae 111 Figure 3. Traditional Meeting House, Maneba 2. Indigenous Navigation and Stars Kiribati consists of a series of small atolls and coral islands situated on the equator. The people of Kiribati developed navigational skills that have been crucial for their survival. According to the information provided by Grimble from the navigator of Butaritari Island (Grimble , 1972: 215– 218), they learned navigational skills at a traditional meeting house, called maneba (Figure 3). Navigators’ lessons began in the maneba when the novice navigators sat at the base of the central pillar facing the eastern slope of the roof. The navigator regarded the sky as a vast roof supported by imaginary rafters (oka)—3 on the eastern slope and 3 on the west (Figure 4). Grimble explained in detail how to conceive astronomical phenomena in relation to the house roof (Figure 5): Just as the roof was divided by vertical lines of rafters, so the heavens were plotted out for him in lines of principal stars. Every constellation was allocated its imaginary place in the thatch, according to what we would call its angula distance east or west of Rigel and its declination north or south of that star. (Grimble, 1972: 215–216). The apex of the middle pair of rafters is held to be at the point where the star Rigel (beta Orion) crosses the meridian. These middle rafters represent the Gilbertese celestial equator, which, being fixed by the declination of Rigel, is seen to be placed about 8° south of our own. The apex of the northern pair of rafters is said to be where the Pleiades cross the meridian which is about 24° north of true celestial equator and 32° north of the Gilbertese; while the 112 A. Goto, H. Ohnishi, and T. Ishimura Figure 4. Inside the Maneba Figure 5. Model of Indigenous Astronomy and Calendar in Kiribati (Makemson, 1941: Figure 4) star Antares (alpha Scorpionis) marks the meeting-point of the southern pair at 26° true south declination, or 18° south of the Gilbertese equator..... Lying across the rafters, like the steps of a ladder up the sky, the astronomer imagines a series of 3 equally spaced crossbeams or purlins on each slope of the roof (Grimble , 1972: 216). Navigators had to memorize the names of more than 178 stars and also learned their courses and positions at particular seasons and times. One of the methods of memorizing the guiding stars Navigation Stones on Arorae 113 Figure 6. Orientation of Navigation Stones Researched by Hilder (Hilder, 1959: Figure 1) was to create a tale about them, wherein they figured as persons or objects seen during the voyage. Folk stories were often adapted to this purpose. Navigators watched the stars lying on their backs on the outrigger platform. Sometimes they turned around and, when they could no longer see any differences in a star’s altitude, that star was at the zenith. They memorized the stars that passed exactly over certain islands and would then try to keep directly beneath them as they approached the islands. On ocean voyages they may also have been able to estimate latitude by observing the meridian altitude of stars nearer the horizon (Grimble, 1972: 218–219). Like Carolinian navigators (Goodenough, 1952 ; Gladwin, 1970), Kiribati navigators also used the sun, wind direction, ocean swells, birds, color of the sea, floating objects, and other indices. 3. Navigation Stones 3.1 Survey by Hilder Hilder first published a map of navigation stones and analyzed their orientation (Table 1). He identified 9 stones as educational tools for navigation and saw the land where stones were distributed as a “navigational school” (Figure 6). 114 A. Goto, H. Ohnishi, and T. Ishimura Figure 7. Estimated Target Island (Hilder, 1959: Figure 2) Hilder considered the easternmost stone, Stone A, whose direction did not seem to be related to those of other stones, as an entrance mark for the school. As for the other stones, Stones F and G are a pair and Stones H and I are another pair. In contrast, the remaining stones, B, C, D, and E, are lain independently. Hilder used a magnetic compass to estimate the orientation of each stone, considering the offset value (between true north and magnetic north). He then suggested to which island each stone or pair of stones was directed (Figure 7): B to Onotoa 305° true, distant 86 miles; C and D to Tamana 273° true, distant 52 miles; F and G to Tamana 286° true, distant 52 miles; H and I to Nukunau 345° true, distant 74 miles (Hilder, 1962: 86). Since Stone C and Stone D had almost the same orientation, Hilder believed both stones were directed toward Tamana Island. Stone C was originally situated near the beach, but the accumulation of sand caused Stone C to be situated inland. That is why another stone, Stone D, was lain near the beach. The pairs H-I and F-G are ideal devices for learning the course of stars used for navigation. The paired stones might be the improved form of a single stone (Figure 8). All the stones were paired originally, but some of the stones were lost, resulting in stones A, B, C, and D being independent. Navigation Stones on Arorae 115 Figure 8. Model of How to Use Navigation Stone (Hilder, 1959: Figure 3) Hilder further considered the reason why pair stones H and I were directed toward Nikunau Island but not to the neighbor island, Beru. Beru lies 23 miles leeward of Nikunau. Hilder argued that if the navigator aimed to reach Nikunau it was easy to go down to Beru with wind. Neither the eastern nor western extension of Stone E is directed toward any island. Hilder argues that the direction of this stone is something mythical and that it may be directed toward “hell,” where outcasts were sent. Hilder’s estimate of the orientation of these stones, however, deviated about 5° from each island. Hilder argued that this systematic error was intentional, considering the effect of Equatorial Current. 3.2 Reanalysis of Ward by Lewis When Captain Ward surveyed these stones in 1946, he found 13 stones except for one that is considered to have been the entrance stone. According to Lewis, who reanalyzed Ward’s data, Hilder collected the names of each stone that indicate toward which island each stone was directed (Table 1). Lewis further pointed out that Hilder’s analysis was based on an interpreter who was not proficient in English, but that Ward himself and his informant could understand Kiribati. Unfortunately, Ward’s research has never been published. A famous researcher of indigenous navigation of the Pacific, Lewis reanalyzed Ward’s manuscript and found differences from Hilder’s estimate. For instance, a pair of stones, G and H, that Hilder considered to be directed toward Tamana, appears to actually be directing eastward toward Orana or Hulu Island in the Phoenix Islands.