Uchide no kozuchi

Uchide-no-Kozuchi (打ち出の小槌^?) is a legendary Japanese "magic hammer" which can "tap out" anything wished for. This treasure is also rendered into English as "magic wishing mallet" or "lucky hammer," "the mallet of fortune", etc.

In popular belief, magic wooden hammer is a standard item held in the hand of the iconic deity Daikoku-ten, who is often represented as figurines, statues, netsukes, and in architecture.

It is also a stock item in popular tales. In Issun-bōshi ("One-Inch Boy"), the hero gains the mallet defeating an ogre (oni) and amass wealth, while in modern embellishments, he even transforms himself into full adult-size. In Momotarō ("Peach Boy"), the mallet is captured from the ogres in Onigashima, alongside the kakure mino (raincoat of invisibility) and kakurekasa (hat of invisibility)

The notion that ogres possessed this prized mallet dates much earlier than the tales, which are part of the otogizōshi collection from the Muromachi Period. It can be traced at as far back as The Tale of Heike (ca. 1240), or, if the instance of use in the work has any historicity, datable to before ca. 1118.

In folkloristics, the uchide no kozuchi is catalogued in the Stith Thompson motif index scheme under ""magic hammer, D 1470.1.46".

In the legend, the one-inch tall Issun-boshi, after leaving his parent's home, comes under the employ of a wealthy daimyo, whose daughter is an attractive princess. Although scorned for his height, he is given the job of accompanying the princess. While traveling together, they are attacked by an Oni, who deals with pesky Issun-boshi by swallowing him. He defeats the Oni by pricking him from within with his needle/sword. The Oni spits out Issun-boshi and drops the 'Uchide-no-Kozuchi as he runs away. In the otogizōshi, he then shakes out opulent riches with the mallet and becomes a court favorite. In the better-known modernized versions, the princess uses the power of the mallet to grow him to full size. At the end of the story, Issun-bōshi and the princess are married.

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