二戰謎圖：日治後期（1924-1945）臺灣五萬分一地形圖再考

The mystery maps during the WWII: Reinvestigating the 1/50000 topographic map in the late colonial period of Taiwan 1924─1945

日治後期五萬分一地形圖是日治時期臺灣最完整也是最後一套大比例尺地形圖。這套地形圖不僅提供了日治前期臺灣中央山地未調查完成的詳細地形資訊，更記錄了1920年大規模行政區劃改正後的完整地名資訊，以及包含蕃地在內的邊界、聚落、道路……等詳細的人文與自然環境資訊，其重要性不可言喻。然而，這套地形圖自1924年開始測量至日本戰敗為止，一再的更新補測，使其成為日治時期測繪期間最長的一套地形圖。再加上二次大戰的戰事影響，使地圖版本更趨複雜，以致目前仍無完整的典藏研究報告，坊間甚至有不少與五萬分一蕃地地形圖混用或誤用的情況。本研究藉由地理資訊系統（GIS）配合相關歷史文獻，將國內外各單位徵集與彙整的日治後期五萬分一地形圖進行系統性的比對，釐清不同版本的繪製脈絡，特別是二次世界大戰期間地圖補測、覆蓋以及應急出版的區域差異。本研究除了凸顯地理資訊系統的套疊分析在地圖彙整比對之意義，也可細緻呈現這套地圖不易得見的地理資訊。本研究的成果也展示了這套地圖在日治後期臺灣歷史地理研究上的價值，以及如何在地圖數位典藏成果上藉由地理資訊系統的分析，將歷史地圖的考察帶入更深一層的研究領域。

The late colonial period’s 1/50000 topographic map is the most completed last Large-Scale topographic maps in Taiwan. This map set not only provides detailed topographical information of Taiwan's central mountain where the investigation had not been investigated completely, but also presents the latest gazetteers after the most important reform of administrative divisions in Colonial Taiwan. Needless to say, it has remarkable achievement by recording the detail natural and humanities information including the aborigine areas.However, the fundamental topographic survey and its supplementary measurement lasted from 1924 to the end of WWII that made it has the longest topographic survey during the colonial period in Taiwan.Besides, as the result of the WWII military activities, the release of cartographic maps became more and more complex that no integral archive research had been reported and lead to cases of mix or misuse with 1/50000 aborigine topographic maps. The study aims to clarify the mapping context among different versions of the late colonial period’s 1/50000 topographic maps, especially the regional difference of additional survey, fortress cover, and the emergency release during the WWII. The digital form of late colonial period’s 1/50000 topographic maps collected around the world were systematic analyzed by Geographic Information System ( GIS ) with pivotal historical documents.This study highlights the value of GIS’s overlay analysis in organizing and regularizing hundreds of cartographic maps that reveals the detailed geographic information which was not easy to be seen.The early fruit of this study not only demonstrate the values of the late colonial period’s 1/50000 topographic maps in history and geography studies, but also present how GIS could overstep the digital preservation of maps by bringing the investigation into a further research field.