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[Uchimizu, an Ancient Japanese Custom of Sprinkling Water on Streets and Gardens]

Uchimizu is one of the ways to cool off in summer in Japan. It has long been seen in gardens, in front of stores, and on streets. In ancient times, it was meant to purify the way for kami to pass through. Japanese people, who have cultivated fields, have long held the belief in the worship of water deities, and water sources have been revered as sacred places. With the arrival of Buddhism, purification and cleansing by water became even more sacred. Uchimizu was practiced as a courtesy in the world of the tea ceremony during the Sengoku and Azuchi-Momoyama periods, and became popular in the Edo period (1603-1868), when water was sprinkled at entrances and along streets to ease the summer heat and calm dust on the streets to make guests feel welcome.

As water evaporates, it absorbs heat from its surroundings, creating vaporization heat, which cools the air. The water vapor temporarily raises the atmospheric pressure, causing the air to flow toward the higher pressure, which in turn creates a natural breeze. Uchimizu is effective not only on streets and in gardens, but also on balconies and around outdoor units of air conditioners. Around the outdoor unit improves the efficiency of cooling operation and reduces power consumption.

The best time to sprinkle water is in the morning or evening, not during the hot daytime, and it is more effective in the shade than in a place with direct sunlight. Water evaporates quickly in the sun, making it less effective, while water evaporating slowly in the shade is more effective for cooling. However, sprinkling water in the daytime or in the sun is also effective in preventing heat caused by the return of sunlight from the road. And by using rainwater as a secondary source of water for sprinkling, it can be an environmentally friendly and sustainable measure to save electricity.

The coolness felt when touching the water stimulates the senses and makes us feel cooler. On August 4, an uchimizu event was held in various parts of Japan. As the hot days continue, why not experience the natural coolness created by uchimizu?

Rikucho Ogasawara's Nambu Wind Bell
https://www.shokunin.com/en/rikucho/furin.html
Nousaku's Wind Bell
https://www.shokunin.com/en/nousaku/furin.html
Touch Classic's Wind Bell
https://www.shokunin.com/en/touchclassic/furin.html

References
https://ja.wikipedia.org/wiki/打ち水
https://uchimizu.jp/2021/08/1957/
https://www.ntt-f.co.jp/column/0108.html
https://www.jalan.net/news/article/562561/
https://ja.ukiyo-e.org/image/bm/AN00508857_001_l