燧火（本草纲目）主救人四时之疾因时钻取因病而用五色之火煎五脏之药（品汇续集）
【名】榆柳木火 杏枣木火 桑柘木火 柞 木火 槐檀木火【时】（生）四时四季（采）
春夏
季夏秋冬取之【用】取于四时配合五脏【质】榆柳先百木而青故春取之其火色青杏枣之木心
赤故夏取之其火色赤桑柘之木肌黄故季夏取之其火色黄柞 之木里白故秋取之其火色白槐檀
之木心黑故冬取之其火色黑【色】青赤黄白黑【性】热【气】上炎升也阴中之阳也【治】（李
时珍云）周官司 氏四时变国火以救时疾季春出火季秋纳火民咸从之盖人资于火食者疾病寿
夭生焉因时钻燧取新火以为饮食之用依岁气而使无亢不及所以救民之时疾也【禁】（道书云）
灶下炭火谓之伏龙屎不可 香祀神【解】天文大火之次于星为心季春龙见于辰而出火于时为
暑季秋龙伏于戍而纳火于时为寒顺天道而百工之作息皆因之以免水旱灾伤之流行也【赝】后
世寒食禁火乃季春改火遗意而俗作介推事谬矣
桑柴火主痈疽发背不起瘀肉不腐及阴疮瘰 流注 疮顽疮然火吹灭日炙二次未溃拔毒止
痛已溃补接阳气去腐生肌（本草纲目）【用】（李时珍云）桑木能利关节养津液得火则拔引毒
气
而祛逐风寒所以能去腐生新【制】凡一切补药诸膏宜此火煎之【治】（朱震亨云）火以畅达
拔
引郁毒此从治之法也【助】（抱朴子云）一切仙药不得桑煎不服桑乃箕星之精能助药力除风
寒
痹诸痛久服终生不患风疾故也【行】（陈藏器云）桑柴火灸蛇则足见【忌】此火不可点艾伤
肌
燧火（出自《本草纲目》）主治四季发生的疾病，根据时节钻木取火，依据病症使用对应颜色的火来煎煮调理五脏的药物（出自《品汇续集》）。
【名称】榆柳木火、杏枣木火、桑柘木火、柞木火、槐檀木火。
【时令】（生长）于四季之中。（采集）在春夏、季夏及秋冬时节采取。
【用法】根据四季变化配合五脏进行应用。
【质地】榆柳树木先于其他树木发芽变青，所以在春季采取，其火焰颜色为青色；杏枣树木心材为红色，所以在夏季采取，其火焰颜色为赤色；桑柘树木肌理为黄色，所以在季夏（长夏）采取，其火焰颜色为黄色；柞树木里层为白色，所以在秋季采取，其火焰颜色为白色；槐檀树木心材为黑色，所以在冬季采取，其火焰颜色为黑色。
【颜色】青、赤、黄、白、黑。
【性质】热。
【气机】向上炎升，属于阴中之阳。
【治疗】（李时珍说）《周礼·司爟氏》记载四季变更国家之火以救治时令疾病：季春（春季第三个月）取出旧火，季秋（秋季第三个月）收纳旧火，百姓都遵从。大概人类依赖火食，疾病的产生和寿命的长短都与火有关。因此根据时节钻燧取新火作为饮食之用，顺应岁气而使用，避免阳气过亢或不足，从而救治民众的时令疾病。
【禁忌】（道书说）灶下的炭火被称为“伏龙屎”，不可用于烧香祭祀神灵。
【解释】天文星宿中，“大火”星次位于心宿。季春时节，苍龙七宿的角宿出现在辰位，于是出火，此时节为暑热；季秋时节，苍龙七宿的房宿伏于戌位，于是纳火，此时节为寒冷。顺应天道，百工的作息都因此遵循，以避免水旱灾害流行的伤害。
【伪误】后世寒食节禁火的习俗，是季春改火制度的遗留意思，但世俗将其附会为介子推的故事，这是错误的。
桑柴火主治痈疽发背不起、瘀肉不腐，以及阴疮、瘰疬、流注、顽疮等。燃火吹灭后，经日光照射两次，未溃破者可拔毒止痛，已溃破者可补接阳气、去腐生肌（出自《本草纲目》）。
【用法】（李时珍说）桑木能通利关节、滋养津液，得到火的作用则能拔引毒气，祛除风寒，所以能去腐生新。
【炮制】凡是所有的补药和各种膏剂，适宜用此火煎煮。
【治疗】（朱震亨说）火可以畅达拔引郁结之毒，这是从治的方法。
【辅助】（抱朴子说）一切仙药如果没有桑木煎煮就不服用。桑树是箕星的精华，能助药力，祛除风寒痹症等各种疼痛，长期服用终生不会患风疾，就是这个原因。
【行效】（陈藏器说）用桑柴火灸蛇，蛇足会显现出来。
【忌宜】此火不可用来点燃艾草，以免损伤肌肤。
Sui Fire (from *Bencao Gangmu*) is indicated for diseases occurring in the four seasons. Fire is drilled and obtained according to the season, and medicines targeting the five Zang organs are decocted using fire of corresponding colors based on the disease (*Pinhui Xuji*).
[Names] Elm and Willow Wood Fire, Apricot and Jujube Wood Fire, Mulberry and Morus Alata Wood Fire, Oak Wood Fire, Locust and Sandalwood Wood Fire.
[Seasons] (Growth) Throughout the four seasons. (Harvesting) Collected in Spring, Summer, Late Summer, Autumn, and Winter.
[Usage] Applied according to the four seasons to correspond with the five Zang organs.
[Properties] Elm and Willow trees turn green before other trees, so they are harvested in Spring; their fire color is Green. Apricot and Jujube trees have red hearts, so they are harvested in Summer; their fire color is Red. Mulberry and Morus Alata trees have yellow flesh, so they are harvested in Late Summer; their fire color is Yellow. Oak trees have white interiors, so they are harvested in Autumn; their fire color is White. Locust and Sandalwood trees have black hearts, so they are harvested in Winter; their fire color is Black.
[Colors] Green, Red, Yellow, White, Black.
[Nature] Hot.
[Qi Movement] Flaring upward and ascending; it is Yang within Yin.
[Treatment] (Li Shizhen stated) The *Rites of Zhou* records that the Official of Fire changes the national fires in the four seasons to save people from seasonal illnesses: in Late Spring, old fires are removed; in Late Autumn, old fires are stored, and the common people follow this. Generally, humans rely on fire for cooking, and diseases and longevity arise from this. Therefore, new fire is drilled and obtained according to the season for dietary use, following the Qi of the year to prevent excess or deficiency, thereby saving the people from seasonal illnesses.
[Contraindications] (According to Daoist texts) Charcoal fire under the stove is called "Fulong Shi" (Dragon's Stool) and must not be used for burning incense to worship deities.
[Explanation] In astronomy, the star "Da Huo" (Great Fire) is located in the Heart mansion. In Late Spring, the Horn constellation of the Azure Dragon appears in the Chen position, and fire is issued; the season is hot. In Late Autumn, the Room constellation of the Azure Dragon hides in the Xu position, and fire is stored; the season is cold. Following the Way of Heaven, the work and rest of all artisans follow this pattern to avoid the spread of water and drought disasters.
[Falsification] The custom of prohibiting fire during the Cold Food Festival in later generations is a remnant of the Late Spring fire-changing ritual, but popularly attributing it to Jie Tui is erroneous.
Mulberry Wood Fire is indicated for carbuncles and back sores that do not suppurate, necrotic flesh that does not rot, as well as yin sores, scrofula, flowing abscesses, and stubborn ulcers. After igniting the fire and blowing it out, exposing it to sunlight twice, it can extract toxins and stop pain for unruptured lesions, and replenish Yang qi, remove necrotic tissue, and generate new flesh for ruptured lesions (*Bencao Gangmu*).
[Usage] (Li Shizhen stated) Mulberry wood can benefit the joints and nourish body fluids. When acted upon by fire, it draws out toxic qi and expels wind-cold, thus enabling the removal of necrotic tissue and generation of new tissue.
[Processing] All tonifying medicines and various plasters are suitable for decoction using this fire.
[Treatment] (Zhu Zhenheng stated) Fire can facilitate the free flow and extraction of pent-up toxins; this is a method of treating according to the nature of the disease.
[Assistance] (Baopuzi stated) All immortal medicines are not taken without mulberry decoction. Mulberry is the essence of the Ji Star; it assists medicinal power, dispels wind-cold and bi-syndrome pains. Long-term consumption ensures one will never suffer from wind diseases.
[Efficacy] (Chen Cangqi stated) Moxibustion with Mulberry Wood Fire on a snake causes its feet to appear.
[Taboo] This fire must not be used to ignite moxa, as it may damage the skin.