《缉古算经》造仰观台题新解

唐代王孝通《缉古算经》中“假令太史造仰观台”一题是书中的一个典型题目。自清代以来，对它的研究颇多，但该题仍是彻底搞清《缉古算经》的最后一道屏障。以往各家对于仰观台及其反道的形状、台与道的接合方式等问题见解不同，且都难以全合常理。本文提出了一种新的解释，认为仰观台和羡道构成的整体，从几何学上讲，就是由刍童切去一个契形后的剩余部分。羡道的广袤方向与仰观台的广裹方向相同，道与台不是垂直相接，而是紧贴在一起的。这样，以往各种难以说明的问题都得到了合理的解释，且与题文、术文及注文一一吻合。

A NEW STUDY ON THE PROBLEM OF CONSTRUCTING AN OBSERVATORY IN WANG XIAOTONG'S JI GU SVAN JING

There is a problem of constructing an obserVatory in Ji Gu Suan Jing (Continustion of Ancient Mathematics), a famous text written by Wang Xiaotong in the Tang Dynasty.A series of studies have been made on the text since the beginning of the 18th century.However, the shape Of the observatory and the methods of its construction have remained to be a puzzle. In this paper, the author deals with the problem and makes some new points as regards the shape of the obseryatory and the methods of its construction. All questions about the Problem are answered.