This kind of information depends on actual measurements. Since Japan intended to invade Taiwan, they must have had these kinds of maps. "This is a suspicion Wei Te-wen held throughout his many years of studying Taiwan maps.
這些訊息都要靠實際測量，日本既然有意攻打台灣，一定有這種地圖，」這是魏德文多年鑽研台灣古地圖，存放於心的疑問。