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Take half a *jin* (approx. 500g) of clean *Puxiao* (Mirabilite, Natrii Sulfas), place it in a jar, and melt it over charcoal fire. Continue to boil until it turns red and dries out. Extinguish the fire, allow it to cool and solidify, then remove it; this becomes *Xiaoshi* (Niter/Potassium Nitrate). Store it for future use.

Take one *jin* of lead, place it in a small jar, and melt it using charcoal fire. Throw two *liang* (approx. 60g) of *Baipi* (White Arsenic, Realgar/Orpiment mixture) onto the molten lead. Refine until all smoke has dissipated. After cooling and solidifying, open the container. The golden-topped arsenic will crystallize on the surface of the lead. Remove it and store it for use.

"Red Lead" refers to the menstrual blood from a woman's first menstruation. When a woman reaches the age of fourteen (two times seven years), her *Tian Gui* (Heavenly Water/Menstrual Blood) arrives. This is considered the true Yang within Yin, the primordial source of Qi and Blood. Before menstruation begins, her cheeks often appear like peach blossoms, indicating that Yang is manifesting while Yin is storing; menstruation will definitely occur within half a month. Prepare one chi five cun (approx. 50cm) of white raw silk cloth, washed clean. When the flow starts, it resembles fish eyes, red and bright, with luster like pearls; collect the remaining flow using the silk cloth. Dry it in the shade, then soak it in clear urine from a young boy (Tong Bian). After a short while, the menstrual blood will naturally detach from the cloth. Gather it in a porcelain basin and dry it in the shade for use. For subsequent menstruations, if the woman has not yet lost her virginity, they can also be collected. Dry them in the shade in a porcelain basin and refine them by sublimation; the color will resemble purple frost. The first occurrence is a precious treasure for extending life. Take it mixed with aged wine. If taken in excess causing unconsciousness or drunkenness, drink human milk, and she will recover naturally later. If sexual abstinence is maintained after taking it, life can be extended by one cycle of twelve years. Subsequent menstrual blood, if combined into "Er Yuan Dan" (Two Primordial Elixir) and taken with human milk, can also extend life and cure various diseases. This prescription is extremely mysterious and should not be lightly disclosed.

The main therapeutic functions of this product include treating arsenic poisoning and pufferfish poisoning, both with extreme efficacy. It can also treat conditions such as mania caused by Yang toxicity in Cold Damage (Shanghan), Ding sores (carbuncles/furuncles), Sha syndrome (sand disease/toxic heat), and internal invasion of toxic qi causing restlessness, thirst, and a large, forceful pulse. [Note: The original text contains a gap here regarding the preparation of "Jin Zhi"]. Take a section of large bamboo consisting of two connected nodes, shave off half of the outer green skin with a knife... this is Jin Zhi (Golden Juice). Store in a porcelain jar for use.

Regardless of size, all toads possess Su (Toad Venom/Cerumen). To extract it, use wide copper tweezers to pinch the fleshy gland above the toad's brow ridge tightly, then quickly pull away. The venom will condense in the tweezers. Scrape off the accumulated venom and dry it in the shade. The toad, having been harvested, should be kept away from wind for two days, then returned to the grassy garden; it will not suffer harm to its life.