The Eight Techniques of the Spirit Tortoise, woodcut

Woodcut illustration from an edition of 1591 (19th year of the Wanli reign period of the Ming dynasty). The eight techniques of the Spirit Tortoise are also known as the flights of the Spirit Tortoise, the eight flying techniques and the divination techniques of the Extraordinary Channels (qi jing).This is a method based on the eight points of the Eight Extraordinary Channels (qi jing ba mai), in conjunction with the alternations of the Eight Trigrams (ba gua), the Nine Palaces, and the Celestial Stems and Earthly Branches. It was used to establish the strength or weakness of the patient's blood and Qi and hence to determine the appropriate course of acupuncture for a particular day and time.

Picture title: Illustration of the Eight Techniques of the Spirit Tortoise. Other lettering: Kan (Water trigram) 1 Shenmai (Extending Vessel); gen (Mountain trigram) 8 neiguan (Inner Pass); zhen (Thunder trigram) 3 waiguan (Outer Pass); xun (Mild Wind trigram) linqi (Close to tears); li (Fire trigram 9 ) lieque (Break in the Sequence); kun (Earth trigram) 2 5 zhaohai (Shining Sea); dui (Lake trigram) 7 houxi (Back Stream); gan (stem); 6 gongsun (Grandfather Grandson)