Ungaikyo (雲外鏡)
The term "Ungaikyo" is a type of a Japanese ghost, that metamorphizes from a peculiar mirror after the passing of many long years. Ungaikyo was illustrated in the ghosts' collection "Hyakki Tsurezure Bukuro" (A Hundred Gods of Things Imagined in Idleness) made in 1784 by Sekien TORIYAMA, who was an ukiyoe (Japanese woodblock print) artist.
Seen from a folkloric perspective, Ungaikyo is a mirror version of "Tsukumo-gami" (gods of a variety of things).
Sekien's Ungaikyo
Sekien illustrates a mirror called 'Shomakyo,' in which the image of a ghost appears and then changes into the actual ghost itself after a number of years have passed by. Ungaikyo in "Hyakki Tsurezure Bukuro" (cf. the upper right image) was illustrated as a round mirror in a Court noble's residence. The right half of the mirror is hidden behind a blind screen, accompanied by a weird black cloud (or by a mirror stand with such a design). And in the mirror is the face of an evil-looking ghost staring at us with its tongue out.
Researchers' analysis and comments
Some people, like Katsumi TADA, a ghost researcher and a writer, explain in their books that Ungaikyo is a mirror version of Tsukumo-gami.
And the comic artist Shigeru MIZUKI, who produced many comic books about ghosts, explains as follows:
If you run water into a tray made from quartz - under the moonlight on the fifteenth night of the eighth lunar month - and portray a ghost on a mirror with the water, a ghost will haunt the mirror. This mirror is called Ungaikyo, he says.
Distortion
Based on the modern mass media culture, picture books of ghosts or collections of paintings of ghosts distort the form of Ungaikyo into, for example, a ghost like raccoon dog disguised as a mirror (a raccoon dog whose body incorporates a mirror), or a ghost that can project various images on its own body. However, Kenji MURAKAMI, a ghost researcher and a writer, points out such Ungaikyo that have a distorted figure and is exaggerated in its capability, originated from the Ungaikyo that appeared as an old-looking raccoon dog in "Yokai Daisenso" (The Great War of Ghosts), a special effects movie made in 1968. He says images of Ungaikyo created after that were imitations influenced by the above.
Other supernatural mirrors
A mirror that has many similarities to Ungaikyo, and other supernatural mirrors - though not similar to Ungaikyo - are explained below.
"Shoyokyo" (also called "Shoyokan") was a mirror that revealed the original shape of the subject that appeared in "Feng-Shen-Yen-I," a bizarre tale created in Ming dynasty of China. Owned by a hermit, Unchushi (雲中子), who lived in Mt. Shunan, Shoyokyo was Paopei (a weapon for senjutsu (the supernatural art of a hermit)), and it could reveal the original shape of the ghost disguised as a human. Shoyokyo has many similarities to Ungaikyo (Shomakyo), the original mirror, before it changes into Ungaikyo ghost.
"Johari no Kagami" is a crystal mirror which is said in Japanese Buddhism to be used by Enma (the King of Hell) for inquiring into if the dead were right-minded or not before its death.
The magic mirror, which appears in the German folklore and fairy tale "Snow White and the Seven Dwarfs," is the one where the spirit of mirror dwells. But this magic mirror is quite different from Ungaikyo, because the former has a strong ego and is characteristic of the crystal ball used in the Western astrology.
Makyo,' a bronze mirror existing in both ancient China and Japan, has a feature that shows an image making use of light refraction. "Kakure Kirishitan Kagami" was the mirror used by underground Christians in feudal Japan.