The New Book of Táng (新唐書) and the Book of Suí (隋書), the official histories of the Táng and Suí Dynasties of China, both record the existence of a now-vanished demonography of legendary origin. ¹

Though the original text and illustrations have been lost, a few fragments of the Baí Zé Tú (白澤圖) survive, quoted in other texts. They all seem to be entries from a catalogue of demons, spooks and monsters, each one listing the type of spirit, its name, and the proper way to avoid being harmed by it or to exploit it for human gain. ²

One such entry goes:
The spirit of abandoned tomb mounds is named Wolf Demon (láng guǐ 狼鬼). It likes to engage people in combat and does not desist. Make a peach bow, jujube arrows, and attach kite feathers to them. Shoot it with them. If Wolf Demon becomes Whirling Wind (piāo fēng 飄風), remove a shoe, throw (the shoe) at it, and it cannot transform.³

Another portion concerning the spirits of valuable minerals is quoted in the fifty-eighth volume of the Táng Dynasty manuscript Fǎ Yuàn Zhū Lín (法苑珠林):

The spirit of jade is called Daì Weǐ (岱委). It takes the form of a beautiful woman and wears blue clothes. When you come across it, if you stab it with a dagger made of peach wood and call out its name, it will become yours.

The spirit of gold is called Cāng Táng (see note). It has two heads on the body of a pig, and when you boil and eat it it has a flavor like dog's meat. ⁴

Just as interesting as the Baí Zé Tú's curious contents is the legend behind its authorship - it was apparently dictated by a monster itself. The story of how Huáng Dì (黄帝, the legendary Yellow Emperor) encountered the wise beast Baí Zé while he was touring in the East was recorded in several sources from the Sixth Century onward. ⁵ One version of the Yellow Emperor's legend states:

Huáng Dì made an imperial visit to inspect the East, and when he went up a mountain here called Mount Huán (桓山), he met a god-beast called Baí Zé. This beast spoke human language well, and knew everything there was to know about every single thing in all of creation. Then the Baí Zé said that, of spirits which have hardened their vital essence and achieved physical form, and apparitions produced by the changing of playful spirits, there are approximately 11520 kinds. Here Huáng Dì commanded that drawings be made based on the things recited by the Baí Zé, and that they be shown to all under heaven, and it became the book called the Baí Zé Tú. ⁶

The Baí Zé is also mentioned in the Classic of the Mountains and Seas (山海経) as a creature living on Mount Dōng Wàng (東望山) in Jiāngnán. It is adept at speaking and appears when the king is virtuous.⁷

In China the Baí Zé beast is usually portrayed with a lion-like shape, but when it was imported to Japan its image became slowly altered, first with horns and hooves and later with a bearded human face, an extra eye in the forehead and two horns and three eyes on each flank, leaving it with an auspicious nine eyes. This fortuitous image, representing a creature who removed the harm of evil spirits, became very popular as a good luck charm in the Edo Period. Today many representations the Hakutaku (the Baí Zé's Japanese name) remain, as protective amulets for travelers and against calamity and disease, as the guardian deities of medicinal shops, and as all manner of objects created in pursuit of a better fortune. ⁸



Sources:
• Harper, Donald. "A Chinese Demonography of the Third Century B.C." Harvard Journal of Asiatic Studies 45.2 (1985): pp 491-4.
• Tada, Katsumi 多田克己 and Natsuhiko Kyōgoku 京極夏彦. Hyakki Kaidoku 百鬼解読 (Deciphering the Hundred Demons). Tokyo: Kodansha, 2006. p 247-50.

Citations:
1. Harper p. 491 and Tada p. 248.
2. Harper p. 492.
3. Harper p. 493. Harper's translation with romanizations changed to modern Pinyin. Source is given as "Pai tse t'u (Yü han shan fang chi i shu ed.), 3b."
4. Tada p. 248. Cāng Táng is written 倉[口唐], where the bracketed portion represents the components of a character not yet renderable in unicode.
5. Harper p. 491.
6. Tada pp. 247-8. The book names this text as 黄帝内伝, but this appears to be a Japanese rendering of the title.
7. Tada p. 247.
8. Tada pp. 249-50