（《拾遗》）
【主治】以器承取，沐头，长毛发，令黑润；朝朝用梳摩小儿头，久觉有益也（藏器）。
【附方】新一。
小儿诸疮，遍身或面上生疮，烂成孔臼，如大人杨梅疮，用蒸糯米时甑蓬四边滴下气水，
以盘承取，扫疮上，不数日即效。百药不效者，用之神妙。（《集简方》）
（《纲目》）
【主治】性滑，上可至颠，下可至泉，宜煎四末之药（虞抟）。
（《拾遗》）
【主治】恶疮久不瘥，煎沸入盐洗之，不过三五度，立效（藏器）。
（《纲目》）
【气味】咸，寒，无毒。
时珍曰∶洗手则生癣。
【主治】利小便，消热肿（时珍）。
【附方】新五。
小便不通∶磨刀交股水一盏，服之效。（《集简方》）
肛门肿痛，欲作痔疮∶急取屠刀磨水服，甚效。（《集简方》）
盘肠生产，肠干不上者∶以磨刀水少润肠，煎好磁石二杯，温服，自然收上，乃扁鹊方
也。
蛇咬毒攻入腹∶以两刀于水中相摩，饮其汁。（《救急方》）
耳中卒痛∶磨刀铁浆，滴入即愈。（《活人心统》）
（《纲目》）
【气味】辛、苦，寒，无毒。
【主治】除热，解毒，杀虫。治误吞水蛭成积，胀痛黄瘦，饮之，取下则愈（时珍）。
染
布水，疗咽喉病及噎疾，温服一钟，良（时珍）。
【发明】时珍曰∶蓝水、染布水，皆取蓝及锻石能杀虫解毒之义。昔有人因醉饮田中水，
误吞水蛭，胸腹胀痛，面黄，遍医不效。因宿店中渴甚，误饮此水，大泻数行，平明视之，
水蛭无数，其病顿愈也。
(From *Bencao Shiyi* [Supplement to Materia Medica])
[Indications] Collected in vessels for bathing the head, it promotes hair growth and makes hair black and lustrous; combing a child's head daily with a comb is considered beneficial over time (Chen Zangqi).
[Additional Prescriptions] One new prescription.
Various sores in children, appearing all over the body or on the face, ulcerating into crater-like holes similar to condyloma lata in adults: Use the "vapor water" dripping from the edges of the steamer basket when steaming glutinous rice. Collect it in a dish and apply/sweep it onto the sores. Effect is seen within a few days. When other medicines fail, this method is miraculous (*Jijian Fang*).
(From *Bencao Gangmu*)
[Indications] Its nature is slippery; it can reach upwards to the vertex and downwards to the sole. It is suitable for decocting medicines intended for the four extremities (Yu Tuan).
(From *Bencao Shiyi* [Supplement to Materia Medica])
[Indications] For chronic malignant sores that do not heal: Boil it, add salt, and wash the affected area. Within three to five applications, immediate effect is achieved (Chen Zangqi).
(From *Bencao Gangmu*)
[Flavor and Nature] Salty, cold, non-toxic.
Li Shizhen states: Washing hands with it causes tinea (scabies-like skin lesions).
[Indications] Promotes urination, reduces heat-induced swelling (Li Shizhen).
[Additional Prescriptions] Five new prescriptions.
Urinary retention: Take one cup of water collected where two whetstones cross during grinding; ingestion is effective (*Jijian Fang*).
Anal swelling and pain, impending hemorrhoids: Immediately take the water from grinding a butcher's knife and ingest it; very effective (*Jijian Fang*).
Prolapsed rectum during childbirth, dry intestine unable to retract: Moisten the intestine slightly with grinding water, decoct two cups of Magnetitum (Cishi), and take warm; it will naturally retract. This is a formula from Bian Que.
Snake bite venom attacking the abdomen: Rub two knives together in water and drink the juice (*Jiuji Fang*).
Sudden ear pain: Drip iron-rich slurry from knife grinding into the ear; it heals immediately (*Huoren Xintong*).
(From *Bencao Gangmu*)
[Flavor and Nature] Pungent, bitter, cold, non-toxic.
[Indications] Clears heat, detoxifies, kills parasites. Treats accumulation caused by accidentally swallowing leeches, characterized by abdominal distension and pain, yellowish complexion, and emaciation. Ingesting this water expels the leeches, leading to recovery (Li Shizhen).
Dyeing water treats throat diseases and dysphagia (Yie disease); taken warm in one cup, it is beneficial (Li Shizhen).
[Elucidation] Li Shizhen states: Both Indigofera tinctoria water (Lan shui) and cloth-dyeing water derive their efficacy from the insecticidal and detoxifying properties of Indigo naturalis (Qingdai) and calcined gypsum/iron-rich stones (Duanshi). Once, a person drank field water while intoxicated and accidentally swallowed leeches, resulting in chest and abdominal distension and pain, yellowish face, and no response to various physicians. Thirsty while staying at an inn, he mistakenly drank this dyeing water, suffered several episodes of severe diarrhea, and upon inspection at dawn, found countless leeches in the stool. His illness was instantly cured.