The roots, shoots, leaves, and fruits of the ear-related plant are all collected, washed to remove sand and soil, hung in a cool place to dry, swept clean on the ground, and burned into ash. Hot water is poured over the ash to leach out the concentrated lye, which is then applied to two stoves for refining. When the lye level drops, fresh boiling lye from adjacent pots is added immediately. Fire is maintained without interruption for one day and one night until frost-like crystals form. These are stored in a dry porcelain bottle. Every morning and evening before sleep, one *qianbi* (an ancient unit of weight) is mixed with wine and taken orally. It has the effects of warming the body, dispelling wind, and preserving youthfulness, with benefits beyond description. It is particularly effective in treating skin wind pathogens, making the skin smooth and clean. A small amount can be used during face washing or bathing, similar to using bath beans, which is especially good, with no dietary restrictions. Congjian, father of Changtu, served as a Literary Official in Yizhou and resided in Yongzhou. He took this medicine for over ten years and is now in his seventies or eighties, yet remains ruddy, light, and vigorous, entirely due to this specific remedy. (From *Liangfang*)

Zheng Yun, a Prime Minister of the Tang Dynasty, said: "When I served as the Military Governor of Nanhai, I was seventy-five years old. The Lingnan region is low-lying and damp, causing internal and external pathogenic factors to attack simultaneously, resulting in various diseases arising together and the decline and exhaustion of Yang Qi. Various medicinal supplements derived from mineral drugs (*rushii*) were tried but failed. In the 7th year of Yuanhe (812 AD), Li Mohe, a shipowner from the Kingdom of Heling (modern-day Java, Indonesia), presented this formula. After taking it for seven or eight days, efficacy was felt. Since then, regular use has proven miraculous. In the second month of the 10th year, upon resigning from my post and returning to the capital, I recorded this formula to pass it on. The prescription uses: *Po Gu Zhi* (Psoraleae Fructus) 10 *liang*, selected, washed, and ground into powder; Walnut meat 20 *liang*, peeled and ground into a paste. The powder is mixed into the walnut paste, combined evenly with refined fine honey to a consistency like maltose syrup, and stored in a porcelain container. In the morning, one spoonful is dissolved in warm wine and taken; if alcohol is not consumed, warm water may be used. Long-term use extends life, tonifies Qi, soothes the mind, brightens the eyes, and strengthens bones and sinews. Avoid eating rapeseed greens (*Yuntao*) and mutton blood. Barbarians call this 'Boguzhi Pill'." (From *Benshi Fang*)

Shi Cangyong, a native of Shu, traveled to the capital practicing medicine and became highly renowned. Chen Cheng, from Yuhang, also gained fame through his medical skills. Shi favored warm-natured herbs, while Chen favored cold-natured herbs. Ancient excellent physicians would always assess the patient's deficiency or excess, observe the Yin-Yang nature of the disease, and then administer decoctions, either tonifying or purging according to the specific condition. However, these two held biased views, insisting on either warmth or coldness. As the saying goes: "Under Shi Cangyong's eaves lie three dou of fire [indicating preference for hot medicines]; inside Chen Cheng's chest lies a plate of ice [indicating preference for cold medicines]." (From *Bozhai Bian*)

Zhou Liheng once recounted: "When I served as an official in the Hanlin Academy, a colleague suffered from an illness characterized by whole-body pain, unbearable during attacks. Physicians in the capital diagnosed it variously as wind-stroke, damp-wind invasion, or gout (*Xianggangjiao*), but none of the medications worked. Suspecting qi-blood stagnation, I prepared a powder for him, which proved very effective. At that time, I had not asked about the specific ingredients. After deep contemplation, I stated: 'Based on this syndrome, *Yan Hu Suo* (Corydalis Rhizome) is indispensable.' Lord Zhou was greatly astonished and asked, 'How did you know?' I replied, 'I deduced it by reasoning; it seemed likely.' The formula consists of equal parts *Yan Hu Suo* and *Dang Gui* (Angelicae Sinensis Radix), processed into powder according to standard methods. During an attack, 3–4 *qian* are mixed with warm wine and administered frequently, adjusted according to the patient's tolerance to alcohol, stopping when relief is achieved. This is because *Yan Hu Suo* is the premier herb for invigorating blood and regulating qi. Later, Zhao Daizhi Ting suffered limb spasms and contractures due to improper practice of *Dao Yin* (ancient therapeutic exercises). Several doses of this remedy cured him."