This Chapter from the Yellow Emperor's Classic of Internal Medicine, details the measurements of the body's meridian pathways within traditional Chinese medicine. It describes the lengths of various meridians, differentiating between yin and yang channels of the hands and feet, and the unique characteristics of the Qiao Mai (Heel Vessels), Du Mai (Governing Vessel), and Ren Mai (Conception Vessel). The text also explores the relationships between the five zang organs and the seven orifices, the consequences of imbalances between yin and yang, and the cyclical nature of qi flow within the meridians. Finally, it explains the flow of qi to the zang organs and the role of meridians in maintaining health and preventing disease.