Tung T'ung-ho (1911-1963) - 董同龢 and Zhou Zumo (1914-1991) 周祖謨 are two of the earliest members of the Institute of History and Philology, Academia Sinica. On October 19, 1936 both of them went from Peking to Nanking to report for duty as Research Assistant of the Institute. Both of them were bachelors then and according to Zhou Zumo's own account, they shared a double room in the dormitory and often discussed phonological matters late into the night. What were the topics of their discussion? In Zhou Zumo's bibliography one can find his paper on the phonological system of the Yupian 玉篇 (1936), "An exegesis of the phonological chapter in Yan Zhitui's Family Instructions for the Yan Clan" 顏氏家訓音辭篇注補 (1943) and "The nature of the Qieyun 切韻 and the basis for its phonological system " 切韻的性質和它的音系基礎 (1963). In the last paper, Zhou Zumo showed that there were two major dialects during the Six Dynasties Period, the Jiangdong 江東 dialect in the south and the Hebei 河北 dialect in the north, and that the Qieyun is a composite work, based upon two distinct dialects. Tung T'ung-ho on the other hand, always believed that the Qieyun is a unitary work. Zhou Zumo's work was to have a lasting influence in my attempt to understand the history of the Wu dialects. This paper imagines a dialogue between Zhou Zumo and Tung T'ung-ho in 1936-37 on the nature of the Qieyun. It is written as a tribute to my teachers.