（《纲目》）
【释名】水银霜、白雪（《纲目》）、白灵砂。
时珍曰∶以汞粉转升成霜，故曰粉霜。《抱朴子》云∶白雪，粉霜也。以海卤为匮，盖
以土鼎。勿泄精华，七日乃成。要足阳气，不为阴侵。惟姜、藕、地丁、河车，可以炼之点
化。在仙，为玄壶；在人，为精原；在丹为木精；在造化为白雪；在天为甘露。
【修治】时珍曰∶升炼法∶用真汞粉一两，入瓦罐内令匀。以灯盏仰盖罐口，盐泥涂缝。
先以小炭火铺罐底四围，以水湿纸不住手在灯盏内擦，勿令间断。逐渐加火，至罐颈住火。
冷定取出，即成霜如白蜡。按《外台秘要》载古方崔氏造水银霜法云∶用水银十两，石硫黄
十两，各以一铛熬之。良久银热黄硝，急倾入一铛，少缓即不相入，仍急搅之。良久硫成灰，
银不见，乃下伏龙肝末十两，盐末一两，搅之。别以盐末铺铛底一分，入药在上，又以盐末
盖面一分，以瓦盆覆之，盐土和泥涂缝，炭火 一伏时，先文后武，开盆刷下，凡一转。后
分旧土为四分，以一分和霜，入盐末二两，如前法飞之讫。又以土一分，盐末二两，和飞如
前，凡四转。土尽更用新土，如此七转，乃成霜用之。此法后人罕知，故附于此云。
【气味】辛，温，有毒。
时珍曰∶畏荞麦秆灰、硫黄。
【主治】下痰涎，消积滞，利水，与轻粉同功（时珍）。
【发明】元素曰∶粉霜、轻粉，亦能洁净腑，去膀胱中垢腻，既毒而损齿，宜少用之。
时珍曰∶其功过与轻粉同。
【附方】新六。
小儿急惊，搐搦涎盛∶粉霜二钱，白牵牛（炒）、轻粉各一钱。为末。每服一字，薄荷
汤下，吐涎为效。（《全婴方》）
小儿躁渴∶粉霜一字，大儿半钱，莲花汤调下。冬月用莲肉。（《保幼大全》）
风热惊狂∶神白丹∶治伤寒积热，及风生惊搐，或如狂病，诸药不效。粉霜一两，（以
白面六钱，和作饼子，炙熟同研），轻粉半两，铅白霜二钱半。为末，滴水丸梧子大。每服
十丸至十五丸，米饮下。（《宣明方》）
疹生翳∶粉霜八分，朱砂一钱。为末。水调少许，倾入耳内。（《鸿飞集》）
腋下狐臭∶粉霜、水银等分，以面脂和涂之。（《圣济录》）杨梅恶疮∶粉霜一味搽之。
（《集简方》）
(From *Bencao Gangmu*)
[Names] Shuiyin Shuang (Mercurial Frost), Baixue (White Snow, from *Bencao Gangmu*), Bailingsha (White Spirit Cinnabar).
Li Shizhen stated: It is called Fen Shuang (Powdered Frost) because it is produced by sublimating mercury powder into a frost-like substance. *Baopuzi* states: "Baixue" is Fen Shuang. It is made using a container crafted from sea salt, covered with an earthen tripod. The essence must not be leaked; it takes seven days to complete. Sufficient Yang Qi is required to prevent Yin invasion. Only Ginger (*Shengjiang*), Lotus Root (*Ouyu*), Field Bindweed Flower (*Diding*), and Placenta Humanum (*Ziheche*) can be used to refine and transform it. Among immortals, it is called Xuanhu; in humans, it is called Jingyuan; in alchemy, it is called Mujing; in creation, it is called Baixue; in the heavens, it is called Ganlu (Sweet Dew).
[Preparation] Li Shizhen stated: The sublimation method: Use one qian of genuine mercury powder, place it evenly in a clay pot. Cover the mouth of the pot upside down with a lamp saucer, and seal the seams with salt mud. First, spread small charcoal fire around the bottom of the pot. Continuously wipe the inside of the lamp saucer with wet paper held in hand without interruption. Gradually increase the heat until the neck of the pot stops heating. After cooling and removing, it forms a frost resembling white wax. According to the ancient prescription for making mercurial frost by Cui recorded in *Waitai Mi Yao*: Use ten liang of mercury and ten liang of realgar (Arsenic Sulfide), each boiled in separate pots. After a long time, when the mercury becomes hot and the realgar melts/nitrates, quickly pour them into one pot; if delayed slightly, they will not mix, so stir urgently. After a long time, the realgar turns to ash, and the mercury disappears. Then add ten liang of Fulonggan (Stove Earth) powder and one liang of salt powder, and stir. Spread one fen thickness of salt powder at the bottom of the pot, place the medicine on top, cover the surface with another fen thickness of salt powder, cover with a clay basin, seal the seams with mud mixed from salt and earth, and roast with charcoal fire for one shichen (two hours), starting with gentle fire then strong fire. Open the basin and brush off the product; this constitutes one cycle. Later, divide the old earth into four parts; use one part to mix with the frost, add two liang of salt powder, and process by flying (levigation/sieving) as before. Again, use one part earth and two liang salt powder, mix and fly as before, totaling four cycles. When the earth is exhausted, use new earth. Repeat this seven times to obtain the frost for use. This method is rarely known by later generations, so it is attached here for reference.
[Properties and Flavor] Acrid, Warm, Toxic.
Li Shizhen stated: It is incompatible with Buckwheat Straw Ash and Realgar.
[Indications] To descend phlegm-saliva, eliminate stagnation, promote urination. Its efficacy is similar to that of Qinfen (Calomel) (Li Shizhen).
[Elucidation] Zhang Yuansu stated: Fen Shuang and Qinfen can also cleanse the fu organs and remove greasy deposits in the bladder. However, due to their toxicity and tendency to damage teeth, they should be used in small amounts.
Li Shizhen stated: Its efficacy surpasses that of Qinfen.
[Attached Prescriptions] Six new prescriptions.
Pediatric acute convulsion with excessive salivation: Fen Shuang 2 qian, Baqian Niu (Fried White Morning Glory Seed) 1 qian, Qinfen 1 qian. Grind into fine powder. Administer one zi dose per time, taken with Mint Decoction. Efficacy is indicated by the expulsion of phlegm-saliva. (*Quanying Fang*)
Pediatric restlessness and thirst: Fen Shiang one zi dose, half a qian for older children, mixed and taken with Lotus Flower Decoction. In winter, use Lotus Seed Meat. (*Baoyou Daquan*)
Wind-heat induced mania and convulsions: Shenbai Dan: Treats accumulated heat from cold damage, wind-induced convulsions, or manic-like conditions where other medicines are ineffective. Fen Shuang 1 liang (mixed with 6 qian white flour to make cakes, roasted and ground together), Qinfen 0.5 liang, Qianbaishuang (Lead Subnitrate) 2.5 qian. Grind into powder, add water drop by drop to form pills the size of wutong seeds. Take 10 to 15 pills per dose with rice drink. (*Xuanming Fang*)
Rash with corneal opacity: Fen Shuang 8 fen, Zhusha (Cinnabar) 1 qian. Grind into powder. Mix with a small amount of water and drip into the ear. (*Hongfei Ji*)
Axillary osmidrosis: Equal parts Fen Shuang and Mercury, mixed with animal fat cream and applied. (*Shengji Lu*) Yangmei severe sores: Apply single ingredient Fen Shuang externally. (*Jijian Fang*)