The Electric Baths of Japan

French electric bath, circa late 1870s. Photo credit: engineeringhistory.tumblr.com

Denkiburo or “electric baths” are found throughout Japan. The bather sits in a small pool between two plates of opposite electric polarity and lets a low-level electric current to pass through their body. The current induces mild shock causing the muscles to contract and develop a tingling sensation which some people find relaxing while others find it painful.

It is used to treat back pain, muscle pain, headaches and migraines, arthritis, disorders of the nervous system, neuromuscular dysfunction and other conditions. Do not try to rig up your own denkiburo by tossing a radio into your tub - that will kill you.
 

More: Amusing Planet

Thanks Bruce!