[Analysis on length of meridians and ebb-flow of ying-qi based on ancient Shushu]

The theories of Shushu in the literature of Qin and Han periods are reorganized and expositions of foreigner scholars about ancient way of thought are consulted, and compared with the recordation about the ebb-flow of ying-qi and the length of meridians in ancient medical books to probe into the relationship between Shushu and these recordation. It is found that the ebb-flow of ying-qi and the length of meridians are completely conform with the principle of Shushu, i. e. the ebb-flow degrees of ying-qi and the length of meridians all are deduced from Shushu for building the close inseparable response relation between nature and humans. Because Shushu can not be verified, modern scientific methods are not suitable to the study on the ebb-flow of ying-qi.