Library

Head (referring to conditions of the head or related herbs; content is listed under the entry for Arisaema Cum Bile / Tian Nan Xing).

*Thomsoniae Radix* (Shan Dou Gen) grows in the valleys of Mount Jian. It is now also found in Guangxi, with those from Zhongzhou and Wanzhou being considered the best. Its vines resemble bean roots, which gives it its name. The leaves are green and do not wither through winter. The roots are harvested in August. Currently, people cut them into inch-long segments and hold them in the mouth to relieve sore throat and swelling, which is extremely effective. In Guangnan, *Thomsoniae Radix* resembles a small locust tree (*Robinia pseudoacacia*), growing over a chi tall. Stone rats eat its roots. Therefore, people in Lingnan capture stone rats, dissect them to take their intestines and stomachs, dry them, and use them to resolve toxicity and clear heat, with very good efficacy.

*Clematidis Radix et Rhizoma* (Wei Ling Xian) originates from Shangluo Mountain in Shangzhou, as well as Mount Hua and flat marshes. It is currently found in various prefectures and military commands in Shaanxi, Hedong, Hebei, Jingdong, and Jianghu regions. When first sprouting, it grows earlier than other grasses. The stems are like the shafts of hairpins, square in cross-section. The leaves resemble willow leaves, arranged in whorls, with six or seven leaves per whorl, resembling a chariot wheel, typically having six to seven layers. Flowers appear in July, light purple or jade-white, in spikes resembling *Acorus calamus* inflorescences, or sometimes resembling chrysanthemum heads. The fruits are green. The root system is dense with many fibrous roots, similar to grain roots, and decays annually. Roots are harvested in September and dried in the shade. Harvesting on Bing (Fire-Yang), Ding (Fire-Yin), Wu (Earth-Yang), or Ji (Earth-Yin) days is preferred, especially from areas where no water sounds can be heard. In the Zhengyuan era of the Tang Dynasty, Songyangzi Zhou Junchao wrote "Biography of Wei Ling Xian": Previously, a person in Shangzhou suffered from a severe illness that prevented him from walking on his feet for decades. Expert doctors exhausted their skills but could not cure him. His relatives placed him by the roadside to seek help. A Silla monk who saw him said: "This disease can be cured with one herb, but I do not know if it exists here." He then went into the mountains to search and indeed found it, which was *Clematidis Radix et Rhizoma*. After taking it, he could walk within a few days. Later, a mountain dweller named Deng Siqi learned of this and spread the story. Cui Yuanliang recorded the method in "Hai Shang Fang": After harvesting, dry in the shade for over a month, grind and sieve. Mix two qian bi (a traditional measure) with warm clear wine and take on an empty stomach. If the patient's constitution tolerates strong medicines, the dose may be increased to six qian bi. If diarrhea exceeds two stools, reduce the dose. Stop taking it when the disease is cured. Its nature is very gentle and does not conflict with other herbs, but it clashes with tea and wheat-based soups. Licorice root (*Glycyrrhizae Radix et Rhizoma*) and Gardenia fruit (*Gardeniae Fructus*) can be used as substitutes for drinking water.