This title, comparable with Huangdi Neijing 黃帝內經 "Yellow Emperor's Inner Canon", is generally interpreted as a "chart" or "diagram" of "inner" "meridians" or "channels" of Traditional Chinese medicine for circulating qi in neidan preventative and observational practices.
All received copies derive from an engraved stele dated 1886 in Beijing's White Cloud Temple 白雲觀 that records how Liu Chengyin 柳誠印 based it on an old silk scroll discovered in a library on Mount Song (in Henan).
In addition, a Qing Dynasty colored scroll Neijing tu was painted at the Ruyi Guan 如意館 "Palace of Fulfilled Wishes" library in the Forbidden City (Despeux 2008:767).
The Neijing tu laterally depicts a human body (resembling either meditator or fetus) as a microcosm of nature – an "inner landscape" (Schipper 1993:100–112) with mountains, rivers, paths, forests, and stars.
The liver and gall bladder are a forest, the stomach is a granary, and the intestines caption reads "the iron ox ploughs the field where coins of gold are sown" (tr.