一名石碱
苦咸微寒，无毒。
《本经》主大热消渴，狂烦，除邪及下蛊毒，柔肌肤。
发明 碱味咸性走，故能消痰磨积，祛热烦。蛊毒、消渴，属实热者宜之。肌肤粗者，
以汤洗之，顽皮渐退，是即柔肌肤之谓也。水碱乃灶灰淋汤，冲银黝脚所造，性能发面，故
面铺中无不用之，病患食之多发浮肿，故方后每忌湿面。观其善涤衣垢，克削可知。
即寒水石
辛咸寒，无毒。近世真者绝不易得，欲验真伪，含之即化为真，
否即是伪。石膏亦名寒水石，与此不同。
《本经》主身热，腹中积聚邪气，皮中如火烧，烦满。
发明 寒水石生积盐之下，得阴凝之气而成，盐之精也。治心肾积热之上药。《本经》
治腹中积聚，咸能软坚也。身热皮中如火烧，咸能降火也。《金匮》风引汤，《局方》紫雪
，皆用以治有余之邪热也。如无真者，戎盐、玄精石皆可代用，总取咸寒降泄之用耳。
辛咸寒，无毒。青白龟背者良。
《本经》除风冷邪气湿痹，益精气。
发明 玄精石禀太阴之精，与盐同性，故其形皆六出，象老阴之数也。《本经》言味咸
气温，传写之误，其气寒而不温，其味辛咸沉降。同硫黄、硝石治上盛下虚，收阳助阴，有
扶危拯逆之功。来复丹用之，专取一阳来复之义，寒因寒用，深得《本经》诸治之奥。
【卤碱】
又名石碱。
味道苦、咸，性质微寒，无毒。
《神农本草经》记载其主治大热引起的消渴症，狂躁烦闷，去除邪气及蛊毒，使肌肤柔嫩。
发明：碱味咸且性善走窜，因此能够消除痰饮、磨化积滞，祛除热邪和烦躁。蛊毒、消渴症属于实热证者适宜使用。肌肤粗糙的人，用热水洗涤患处，顽劣的皮屑逐渐退去，这就是所谓“柔肌肤”的意思。水碱是用灶灰淋滤出的汤液，冲兑银黝脚（一种含盐的沉淀物）所制成，性能发酵面团，所以面铺中无不使用它，病人食用后容易引发浮肿，所以药方后面常忌讳湿面。看它善于洗涤衣物污垢，可知其克削之力很强。
【凝水石】
即寒水石。
味道辛、咸，性质寒，无毒。近代真正的真品极难得到，想要验证真伪，含在口中即刻化为水的是真品，否则就是伪品。石膏也名叫寒水石，但与此不同。
《神农本草经》记载其主治身体发热，腹中积聚邪气，皮肤中感觉如火烧，烦闷胀满。
发明：寒水石生长在积盐之下，得阴凝之气而成，是盐的精粹。是治疗心肾积热的上药。《神农本草经》记载治疗腹中积聚，是因为咸味能软坚散结。身体发热、皮肤中如火烧，是因为咸味能降火。《金匮要略》中的风引汤，《太平惠民和剂局方》中的紫雪，都用它来治疗有余的邪热。如果没有真品，戎盐、玄精石都可以代替使用，总归是取其咸寒降泄的作用罢了。
【玄精石】
味道辛、咸，性质寒，无毒。青白色、背面有龟背纹的是上品。
《神农本草经》记载其去除风冷邪气及湿痹，补益精气。
发明：玄精石禀受太阴之精，与盐同性，所以它的形状都是六角形，象征老阴的数理。《神农本草经》说它味咸气温，这是传抄书写时的错误，实际上它的气是寒而不是温，它的味是辛咸且沉降。同硫黄、硝石一起治疗上盛下虚之证，收敛阳气、资助阴精，有扶危救逆的功效。来复丹中使用它，专门取“一阳来复”的含义，采用“寒因寒用”的方法，深得《神农本草经》各种治疗的奥妙。
[Lunar Salt / Stone Alkali]
Also known as Shi Jian (Stone Alkali).
Bitter, salty, slightly cold, non-toxic.
The *Shennong Bencao Jing* (Divine Farmer's Materia Medica) states it treats severe heat causing polydipsia (excessive thirst), mania and irritability, eliminates pathogenic factors and gu poison, and softens the skin.
Invention: The salty taste and mobile nature of alkali enable it to resolve phlegm and grind down accumulations, dispelling heat and irritability. It is suitable for gu poison and polydipsia presenting as excess-heat syndromes. For those with rough skin, washing with hot water gradually removes stubborn scales; this is what is meant by "softening the skin." Shui Jian (Water Alkali) is made by leaching ashes from kitchen stoves with hot water and mixing them with Yinyou jiao (silver-black sediment/precipitate). Its property allows it to ferment dough, so it is used in all bakeries. However, patients who consume it often develop edema; therefore, prescriptions frequently prohibit the use of wet noodles. Observing its ability to wash away dirt on clothes reveals its strong cutting and scraping power.
[Ning Shui Shi / Congealed Water Stone]
This is Han Shui Shi (Cold Water Stone).
Acrid, salty, cold, non-toxic. Genuine specimens are extremely rare in modern times. To verify authenticity, place it in the mouth; if it dissolves immediately, it is genuine; otherwise, it is fake. Shi Gao (Gypsum Fibrosum) is also called Han Shui Shi, but it is different from this herb.
The *Shennong Bencao Jing* states it treats body fever, accumulation of pathogenic qi in the abdomen, a sensation of fire burning in the skin, and irritability/fullness.
Invention: Han Shui Shi grows beneath accumulated salt, formed by yin condensing qi; it is the essence of salt. It is a superior herb for treating excessive heat accumulating in the Heart and Kidney. The *Shennong Bencao Jing* mentions treating abdominal accumulations because the salty flavor can soften hardness. Body fever and the sensation of fire burning in the skin are treated because the salty flavor can descend fire. Feng Yin Tang (Wind-Dragging Decoction) in the *Jin Gui Yao Lue* (Essential Prescriptions of the Golden Cabinet) and Zi Xue (Purple Snow) in the *Ju Fang* (Formulas of the Bureau) both use it to treat excess pathogenic heat. If genuine specimens are unavailable, Rong Yan (Roc Salt) or Xuan Jing Shi (Mysterious Essence Stone) can be used as substitutes, primarily utilizing their salty-cold descending and purgative properties.
[Xuan Jing Shi / Mysterious Essence Stone]
Acrid, salty, cold, non-toxic. Those that are blue-white with a tortoise-shell pattern on the back are of high quality.
The *Shennong Bencao Jing* states it eliminates wind-cold pathogenic factors and damp-bi syndrome, and benefits essence and qi.
Invention: Xuan Jing Shi inherits the essence of Taiyin (Great Yin) and shares the same nature as salt; thus, its shape is hexagonal, symbolizing the number of Old Yin. The *Shennong Bencao Jing* claims its flavor is salty and its nature warm, which is a transcription error; its nature is actually cold, not warm, and its flavor is acrid-salty with a sinking and descending action. When combined with Liu Huang (Sulfur) and Xiao Shi (Niter), it treats conditions of excess above and deficiency below, consolidating Yang and assisting Yin, possessing the merit of rescuing critical conditions and reversing collapse. It is used in Lai Fu Dan (Restoration Pill), specifically taking the meaning of "one Yang returning," employing the method of "treating cold with cold," deeply grasping the mysteries of the various treatments described in the *Shennong Bencao Jing*.