Zheng Qiao's Tongzhi（The General Documents）is a well-known history book consisting of 20 sections, among which section 3, Qiyin Lue or An Outline on Seven Sounds）, is an important article on classic Chinese phonology. Zheng Qiao says he wrote the article based on a book by a huseng （a foreign monk）. This paper discusses whether that book had been written by a huseng as Zheng Qiao says. The answer is no. However, it is true that the wonderful theory mentioned by Zheng Qiao is closely related to the knowledge of Indian Sanskrit phonology which was indeed brought to China by foreign monks. The other points advocated by Zheng Qiao in his writing are also examined and re-evaluated in the paper.
