Pail of Preservation

The Pail of Preservation (止水桶) is an ancient artifact of the Musk Dynasty which was traditionally used to prevent animals transformed into human women by the Jusenkyo spring, Nyannīchuan, from ever returning to their original forms so that they may give birth to the next generation of the dynasty.

Manga history
At some point into their history the Musk Dynasty acquired the Pail and began using it to seal wild animals into their cursed forms once they were placed into the Spring of Drowned Woman (Nyannīchuan); so that their sons would inherit the traits of the animal they mated with. By modern times, however, this practice was no longer carried out, with members of Dynasty just having strong martial artists from nearby villages bare their children instead.

During the events of the series, Herb, who was arranged to be married, decided he should see what a naked girl looked like first, so took a monkey and the Pail to Nyannīchuan. Once there Herb threw the monkey into the spring, which emerged as a women with a strong resemblance to Ranma's cursed form. Awestruck at this sight, Herb is quickly knocked into the spring by the irate monkey women, cursing herself as well. Shocked by the fact he now has his own breasts, Herb fails to dodge the monkey woman as she throws the cold water of the Pail over him, sealing Herb in his new female form.

Upon learning about the Pot of Liberation, Herb takes Lime and Mint with him to Japan in order to find it's whereabouts, where they encounter Ranma and co, during which time Herb uses the Pail on Ranma for being so insolent to him. Once they learn of it's location on Horai Mountain, Herb uses the Pail's ladle as a dowsing rod for the location of the Pot.