伊能図に基づいたイギリス製日本沿海図

抄録

In 1861, following the Treaty of Yedo in 1858, HMS Actaeon and Dove, assisted by the gunboats Algerine and Leven, visited Kanagawa (Yokohama) and asked the Tokugawa Government the permission of surveying the coast south and westwards to Nagasaki. The Government was in a difficult situation, because it was well aware that anti-foreign feeling ran in the coastal districts. Therefore, Japanese officials were appointed to serve on each of the four ships to meet emergencies. The officials took with them a copy of the Japanese map-a small-scale map in three sheets produced by Tadataka (Chûkei) Inô's survey-which attracted the attention of Commander Ward, captain of Actaeon. He found that the map was so correct and that he could hardly improve on it. Through Sir Rutherford Alcock, the Ambassador, he obtained a copy and it was used to complete the coastline on the relevant Admiralty charts, without getting into trouble with the people of the coastal districts of Japan.
The story was certified by a diary of one of the appointed officials and it has been told with great pleasure in many biographical publications of Tadataka Inô since Meiji era, placing the emphasis upon the fact that the scientific accuracy and reliance of Inô's map were proved by the British surveyors and cartographers. Unfortunately, the fire caused by the Kantô Earthquake in 1923 destroyed the archives Hydrographic Department of Japanese Navy, of Tokyo Geographical Society, etc., and many charts and documents were lost, and little has been known about the copy of Inô's map brought to England by the squadron and the chart produced according to it.
In 1951, N. Pye and W. G. Beasley informed in the article of “An Undescribed Manuscript Copy of Inô Chûkei's Map of Japan” (Geogr. Journal, 117, p. 178-187) that the coastline of the chart produced by the Admiralty (Chart No. 2347, published 15 May 1863) was based on the Inô's map and that the manuscript map of Japan is now on permanent loan to the National Maritime Museum at Greenwich, and geographers and cartographers of Japan have been very much pleased by this information. Recently, through the kindness of Mr. L. N. Pascoe of Hydrographic Department, Ministry of Defence, United Kingdom, the photographic copies of that chart as well as of “Seto Uchi” were sent to Hydrographic Division, Maritime Safety Agency of Japan, and the author had an opportunity to examine these charts (Fig. 3, 4, 5, 6.).
The author illustrated firstly how the coastline of Japanese Islands was correctly improved in these charts as compared with the former Admiralty chart of Japan, which was compiled from Krusenstern's Atlas in 1827 with some corrections afterwards and published in 1862 (Fig. 1, 2.). Secondly the author reviewed some part of the discussions made by N. Pye and W. G. Beasley in 1951 and answered to the questions concerning Ino's survey and the map raised by them. And lastly reviewed relevant part of L. N. Pasco's detailed report in 1969 under the title of “The British Contribution to the Hydrographic Survey and Charting of Japan 1854 to 1883”. The author is indebted to Dr. Kiyoshi Kawakami, Chief Hydrographer, Maritime Safety Agency of Japan for his kindness in making available the sources.