Internal visualisation chart: Intestinal system

Woodcut, incorporated into a handwritten copy of Yuanmen maijue neizhao tu (Internal Visualisation Charts from the 'Primordial Portal' Secrets of the Pulse), attributed to Hua Tuo, a renowned physician of the third century BCE. This chart is a detailed illustration of the intestinal system, i.e. the lower aperture of the stomach is the upper aperture of the small intestine; and the lower aperture of the small intestine -- or 'Door Screen' (lanmen, ileocoecal conjunction) -- is the upper aperture of the large intestine. In the 'Door Screen' section of the small intestine, the products of digestion are divided into 'clear' (qing) and 'turbid' (zhuo); and liquids pass into the bladder to forms urine,while solids pass into the large intestine to form faeces.

PICTURE TITLE: Untitled. OTHER LETTERING: Upper aperture of the small intestine; bladder; ileocoecal conjunction (lanmen); watershed (fenshui)