气热，味酸。
《象》云∶治寒嗽及痰，除肺中寒，大升肺气，少用。款冬花为使。过食损目。
味苦、辛、甘，平。无毒。
《本草》云∶主妇人阴中肿痛，男子阴痿湿痒；除痹气，利关节，癫痫恶疮，温中下气
；令妇人子脏热，男子阴强；久服，轻身、好颜色，令人有子。一名蛇粟、蛇米。五月采，
阴干。恶牡丹、巴豆、贝母。
桂心、肉桂、桂枝附
气温，味甘、辛。有小毒。
入手少阴经。桂枝，入足太阳
《本草》云∶主温中，利肝肺气，心腹寒热冷疾，霍乱转筋，头痛腰痛，出汗，止烦，
止唾，咳嗽鼻 ；能堕胎，坚骨节、通血脉，理疏不足；宣导百药，无所畏。久服，神仙不
老。生桂阳，二月、八月、十月采皮，阴干。有菌桂、牡桂、木桂、筒桂、肉桂、板桂、桂
心、官桂之类。用者罕有分别。《衍义》所言，不知何缘而得官之名。予考《本草》有出观
、宾、宜、韶、钦诸州者，佳。世人以笔画多而懒书之，故只作官也。如写黄檗作黄柏，
作姜同意。菌桂生交趾山谷，牡桂生南海山谷，木桂生桂阳。从岭至海尽有桂树，惟柳州、
象州最多。《本草》所说菌桂、牡桂、板桂，浓薄不同。大抵细薄者为枝、为嫩，浓脂者为
肉、为老，处其身者为中也。不必黄色为桂心，但不用皮与里，止用其身中者为桂心。不经
水而味薄者，亦名柳桂。易老用此，以治虚人，使不生热也。《衍义》谓桂大热。《素问》
谓辛甘发散为阳，故张仲景桂枝汤治伤寒表虚，皆须此药，是专用辛甘之意也。又云∶疗寒
以热。故知三种之桂，不取菌桂、牡桂者，盖此二种性止温而已，不可以治风寒之病。独有
一字桂，《本经》谓甘辛大热，正合《素问》辛甘发散为阳之说，尤知菌桂、牡桂不及也。
然《本经》止言桂，而仲景又言桂枝者，盖亦取其枝上皮也，其本身粗浓处亦不中用。诸家
之说，但各执一己见，终无证据。今又谓之官桂，不知何缘而立名，虑后世以为别物，故于
此书之。又有桂心，此则诸桂之心，不若一字桂也。别说交广商人所贩者，及医家见用，惟
陈藏器之说最是。然筒桂浓实，气味浓重者，宜入治脏及下焦药。轻薄者，宜入治眼目发散
药。《本经》以菌桂养精神，以牡桂利关节。仲景伤寒发汗用桂枝。桂枝者，桂条也，非身
干也，取其轻薄而能发散。一种柳桂，乃小嫩枝条也，尤宜入上焦药。仲景汤液用桂枝发表
，用肉桂补肾，本乎天者亲上，本乎地者亲下，理之自然，性分之所不可移也。一有差易，
为效弥远。岁月既久，习以成弊，宜后世之不及古也。桂心通神，不可言之，至于诸桂数等
，皆大小老壮之不同。观，作官也。《本草》所言有小毒，或云久服神仙不老。虽云小毒，
亦从类化。与黄芩、黄连为使，
参、麦门冬、甘草同用，能调中益气，则可久服。可知此药能护荣气而实卫气，则在足太阳
经也。桂心，入心，则在手少阴也。若指荣字立说，止是血药，故经言通血脉也。若与巴豆
、砂、干漆、穿山甲、水蛭、虻虫如此有毒之类同用，则小毒化为大毒，其类化可知矣。
汤液发汗用桂枝，补肾用肉桂，小柴胡只云加桂何也。《药象》谓肉桂大辛，补下焦热火不
足，治沉寒痼冷，及治表虚自汗。春夏二时为禁药。
《珍》云∶秋冬治下部腹痛，非桂不能止也。
《心》云∶桂枝气味俱轻，故能上行，发散于表；内寒，则肉桂；补阳，则柳桂。桂，
辛热散经寒，引导阳气。若正气虚者，以辛润之。散寒邪，治奔豚。
Properties: Qi is hot, taste is sour.
*Yi Xiang* (Image of Medicines) records: Treats cold cough and phlegm, clears cold from the Lungs, greatly raises Lung Qi, use in small doses. Use *Dong Hua* (Kalanchoe Flower / Tussilago Flos as indicated by context "Kuantonghua" usually refers to *Tussilaginis Flos*, here likely *Adenophorae Radix* or similar depending on specific edition interpretation, but standard is *Tussilaginis Flos* or *Kalanchoe*; given "Kuantonghua" is often *Adenophorae* or *Tussilaginis*, let's stick to literal "Kuantonghua" or standard *Tussilaginis Flos* if implied. However, "Kuan Dong Hua" is *Tussilaginis Flos*. The text says "Kuan Dong Hua". I will use *Tussilaginis Flos*.) as a guiding herb. Overconsumption damages the eyes.
Properties: Taste is bitter, pungent, sweet; nature is neutral. Non-toxic.
*Benzao* (Materia Medica) records: Primarily treats swelling and pain in the female genitalia, male impotence and damp itching in the genital area; removes Bi syndrome qi, benefits the joints, treats epilepsy and malignant sores; warms the Middle Jiao, directs rebellious Qi downward; makes the female uterus warm and enhances male sexual potency; long-term consumption leads to a light body, good complexion, and fertility. Also known as She Su (Snake Millet) and She Mi (Snake Rice). Harvested in May, dried in the shade. Incompatible with Mudan Pi (Tree Peony Bark), Badou (Croton Seed), and Beimu (Fritillaria Bulb).
Notes on Guixin (Cinnamon Heart), Rougui (Cinnamon Bark), and Guizhi (Cinnamon Twig):
Properties: Nature is warm, taste is sweet, pungent. Slightly toxic.
Enters the Hand Shaoyin (Heart) Meridian. Guizhi enters the Foot Taiyang (Bladder) Meridian.
*Benzao* records: Primarily warms the Middle Jiao, benefits Liver and Lung Qi, treats cold-heat disorders in the heart and abdomen, cholera with muscle spasms, headache and lower back pain, induces sweating, stops thirst, stops salivation, treats cough and nasal congestion; can induce abortion, strengthens bone joints, unblocks blood vessels, regulates deficiency in dispersion; promotes all other herbs without fear. Long-term consumption grants immortality like a deity. Grows in Guiyang, harvested in February, August, and October, bark dried in the shade. Varieties include Jungui (Cinnamomum Cassia Blume var. Aromaticum?), Mugui (Cinnamomum Cassia), Mugui (Cinnamomum Camphora?), Tonggui (Tube Cinnamon), Rougui (Meat Cinnamon), Bangui (Board Cinnamon), Guixin (Cinnamon Heart), and Guangui (Official Cinnamon). Users rarely distinguish between them. The explanation in *Yanyi* regarding the origin of the name "Guan" (Official) is unknown. I examined *Benzao*, which states that those from Guan, Bin, Yi, Shao, and Qin prefectures are superior. People omit characters due to laziness in writing, thus writing only "Guan". This is similar to writing Huangbai instead of Huangbo, just as Jiang (Ginger) is written. Jungui grows in the valleys of Jiaozhi, Mugui grows in the valleys of Nanhai, and Mugui (Wood Cinnamon) grows in Guiyang. From Lingnan to the sea, cinnamon trees are everywhere, most abundant in Liuzhou and Xiangzhou. *Benzao* describes differences in thickness among Jungui, Mugui, and Bangui. Generally, thin and fine ones are twigs or tender branches, thick and fatty ones are meat cinnamon or old branches, and the middle part is Guixin. It does not have to be yellow to be Guixin; simply using the middle part without the outer bark and inner pith constitutes Guixin. Those not soaked in water and having a thin taste are also called Liugui (Willow Cinnamon). Yilao uses this to treat deficient persons to prevent heat generation. *Yanyi* states Cinnamon is very hot. *Suwen* states that pungent and sweet disperse and belong to Yang. Therefore, Zhang Zhongjing's Guizhi Tang for treating exterior deficiency in Cold Damage requires this herb, utilizing the meaning of pungent and sweet dispersion. It also states: treat cold with heat. Thus, it is understood that among the three types of Cinnamon, Jungui and Mugui are not selected because their nature is merely warm, insufficient for treating Wind-Cold diseases. Only the "One-Character Cinnamon" (standard Cinnamon) is described in *Benjing* as sweet, pungent, and very hot, perfectly matching the *Suwen* principle of pungent and sweet dispersing as Yang, further proving that Jungui and Mugui are inferior. However, *Benjing* only mentions "Gui", while Zhang Zhongjing mentions "Guizhi", likely taking the bark from the twigs, as the thick trunk is not suitable. Various schools of thought hold personal views without evidence. Now it is called Guangui, and its naming origin is unknown; fearing future generations might consider it a different substance, I record it here. There is also Guixin, which is the center of various Cinnamons, but inferior to the "One-Character Cinnamon". Additionally, merchants from Jiaozhi and Guang sell, and physicians commonly use, what Chen Cangqi describes most accurately. However, Tonggui that is thick and solid with strong aroma is suitable for formulas treating Zang organs and Lower Jiao. Thin and light ones are suitable for formulas treating eyes and for dispersion. *Benjing* states Jungui nourishes spirit, and Mugui benefits joints. Zhang Zhongjing uses Guizhi for inducing sweat in Cold Damage. Guizhi refers to the twig, not the trunk, chosen for its lightness and dispersive ability. One type, Liugui, consists of small tender twigs, especially suitable for Upper Jiao formulas. In *Tangye* (Decoctions), Zhang Zhongjing uses Guizhi to release the exterior and Rougui to tonify the Kidney. This follows the principle that "what originates from Heaven relates to the upper, and what originates from Earth relates to the lower," which is natural law and immutable classification. Any deviation leads to distant efficacy. Over time, habits become弊端 (prejudices/errors), explaining why later generations fall short of the ancients. Guixin connects to the Spirit, which cannot be fully explained. As for the various grades of Cinnamon, they differ in size, age, and strength. "Guan" is written as "Guan". *Benzao* states it has slight toxicity, while some say long-term use grants immortality. Although slightly toxic, it follows the principle of transformation by affinity. If used with Huangqin (Scutellaria Root), Huanglian (Coptis Rhizome) as guides, or combined with Renshen (Ginseng), Maidong (Ophiopogon Tuber), and Gancao (Licorice Root) to regulate the Middle and benefit Qi, it can be taken long-term. It is known that this herb protects Ying (Nutrient) Qi and consolidates Wei (Defensive) Qi, acting on the Foot Taiyang Meridian. Guixin enters the Heart, acting on the Hand Shaoyin Meridian. If discussed solely based on the character "Rong" (Nutrient/Blood), it is a Blood herb, hence the classic text says it unblocks blood vessels. If used with toxic substances such as Badou (Croton Seed), Sharen (Amomum Fruit), Ganqi (Dry Lacquer), Chuanshanjia (Pangolin Scale), Shuizhi (Leech), and Mengchong (Horsefly Larva), the slight toxicity transforms into major toxicity, demonstrating the principle of transformation by affinity. In *Tangye*, Guizhi is used for sweating, Rougui for tonifying the Kidney. Why does Xiao Chaihu Tang simply say "add Gui"? *Yaoxiang* states Rougui is highly pungent, tonifies deficiency of Fire-Heat in the Lower Jiao, treats deep-seated cold and stubborn chill, and treats spontaneous sweating due to exterior deficiency. It is contraindicated in Spring and Summer.
*Zhenzhu Nang* records: In Autumn and Winter, to treat abdominal pain in the lower body, only Cinnamon can stop it.
*Xinfa* records: Guizhi has light aroma and taste, thus it ascends and disperses at the exterior; for interior cold, use Rougui; for tonifying Yang, use Liugui. Cinnamon is pungent and hot, dispersing cold in the meridians and guiding Yang Qi. If Zheng Qi (Upright Qi) is deficient, moisten it with Pungency. Disperses Cold Evil, treats Ben Tun (Running Piglet).