一九五○年到五二年我們的測區幾乎全是山區和丘陵地带,在绘图方面时常得用心算,加减的數字往往达到四位數,實在消耗精力,同時還常有將地形點子算错的可能,這种错又無法找出,對我們地形的精确度有很大的影响。我們就針對着這個问题開動脑筋往里鑽研,後來想到寒暑表上攝華氏的换算法,於是就拿两根三稜尺去實驗。 From 1950 to 1982, the surveyed areas are almost all mountainous and hilly areas. They often have to figure out their drawings. The figures for additions and subtractions tend to reach four digits, which is very energy consuming. At the same time, The possibility of miscalculation, which can not be found out, has a great impact on the accuracy of our terrain. We focused on this issue to start thinking inside, then think of thermometer Fahrenheit conversion method, so take two three-foot ruler to experiment.