Library

Cinnamon (Guì): Jun Gui (Jun Cinnamon) grows in the valleys of Jiaozhi. Mu Gui (Mu Cinnamon) grows in the valleys of Nanhai. Gui (Cinnamon) grows in Guiyang. Old records describe the differences among these three types, noting that their properties, flavors, and functions also differ. However, *Erya* only mentions one type: "Qin, Mu Gui" (Qin, Tree Cinnamon). Guo Pu stated: People in the south call cinnamon; those with thick bark are called Mu Gui. Su Gong believed that Mu Gui is the same as Mu Gui, and that the single name "Gui" refers to this type. Currently, products from the Lingnan region include names such as Tong Gui (Tube Cinnamon), Rou Gui (Meat Cinnamon), Gui Xin (Cinnamon Heart), Guan Gui (Official Cinnamon), and Ban Gui (Board Cinnamon), but physicians rarely distinguish between them when using them. Old theories state that Jun Gui is perfectly round like bamboo, with two or three layers, which corresponds to what is now called Tong Gui. The characters for "Tong" and "Jun" are similar, suggesting a possible copying error. Some say it is the same as Rou Gui. Mu Gui has thin, yellowish bark with little fat tissue, its aroma resembles Magnolia denudata (Mulan), and its taste is similar; after scraping off the outer bark, it is named Gui Xin. It is suspected that what is now called Guan Gui is this type. Gui, which is semi-curved and rich in oil, is suspected to be what is now called Ban Gui. Observing the illustrations from Binzhou, Yizhou, Shaozhou, and Qinzhou, the varieties are indeed different, yet all are labeled simply as "Gui" without other specific names. Referencing old annotations, Jun Gui has leaves resembling persimmon leaves, with three distinct veins in the middle, tight texture, thin as bamboo, and both large branches, small branches, and bark are tubular, resembling current products from Binzhou. Mu Gui has leaves narrower than Jun Gui but several times longer; its tender branch bark is semi-curved and purplish, resembling current products from Yizhou and Shaozhou. Locals there call its bark Mulan Pi (Magnolia Bark) and its meat Gui Xin. There are yellow and purple colors, further verifying this. Gui has leaves resembling cypress leaves, dark and glossy, with yellow bark and reddish heartwood; current products from Qinzhou have dense, fine leaves and are likely of this category, though the leaf shape not resembling cypress causes some doubt. Thick-barked ones are called Mu Gui, which is Ban Gui. Su Gong's assertion that Mu Gui and single-named Gui are the same substance cannot be fully relied upon. These trees grow three to four zhang high, mostly in deep mountains and barbarian caves, though some are planted in household gardens. Transplanted north of the Lingling Mountains, their aroma loses much of its pungency and spiciness, rendering them unsuitable for medicinal use. They flower in March and April, looking entirely like Cornus officinalis (Zhuyu). They bear fruit in September, which people often use to decorate flowers and fruits for banquets. Its leaves are very fragrant and make an excellent tea additive. The bark is harvested in February and August; flowers are harvested in September. Both should be dried in the shade and must not be exposed to fire. Among the Middle Grade herbs, there is also Tianzhu Gui (Indian Cinnamon), said to grow in Western Hu countries. Its function is similar to Gui but less potent. It is currently rare, so it is merely appended here. Zhang Zhongjing used Guizhi Tang (Cinnamon Twig Decoction) to treat Shanghan (Cold Damage). *Jiayi Jing* describes an internal warming method for Bi syndrome caused by Yin pathogen invasion: Use 20 dou of strong wine, 1 dou of Shujiao (Sichuan Pepper), 1 dou of Ganjiang (Dried Ginger), and 1 dou of Gui (Cinnamon). Coarsely crush these four substances, place them in clear wine, along with 1 jin of cotton wadding and 4 zhang of fine white cloth. Submerge everything in the wine, place in fermenting horse manure, seal tightly to prevent gas leakage, and leave for five days and nights. Then remove the cloth and cotton wadding, dry them in the sun, and re-soak them to extract all juices. Each soaking must last a full day before removing and drying the cloth and cotton again. Mix the dregs with the cotton to make towels; the cloth should be six to seven chi long, making six or seven towels. When using, heat the towels over mulberry charcoal and apply to the site of cold-Bi pain to drive heat into the lesion. When cool, reheat and apply again, repeating thirty times until finished. If sweating occurs, wipe the body with the heated towel, also thirty times. Return home immediately and avoid wind. Every acupuncture point treated must be followed by this warming therapy; thus the disease will be cured. This is called internal warming. For treating tendon tension, mix Gui powder with white wine and apply externally. *Xu Chuanxin Fang* describes the method for making Gui Jiang (Cinnamon Syrup): Drink in summer to relieve thirst and irritability, benefit Qi, and resolve phlegm. Take two large liang of Gui powder and one sheng of white honey. Boil two dou of water down to one dou, let cool, and pour into a new porcelain jar. Add the two ingredients, stir two or three hundred turns to mix evenly. Cover first with a single layer of oiled paper, then seven layers of regular paper, and seal tightly with rope. Remove one layer of paper each day. After seven days, open it; the medicine is ready, with a pleasant aroma and flavor, possessing exceptional elegance. Many people today still make this, so the method is recorded here.