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Flickr photo of the day: Thank saltpeter for that

Michael Clemmer
July 4, 2013

It is said that about 2,000 years ago, during the Song Dynasty, a Chinese cook spilled saltpeter onto a cooking fire and made a really pretty flame. Used since time immemorial as a food preservative and additive, saltpeter (potassium nitrate) was also believed to be an anaphrodisiac that, when ingested, would cause men to become temporally impotent.

The cook told his friends about the pretty flame, experimentation followed, and — BANG! — gunpowder was invented. Then a monk named Li Tian thought of putting the new invention into bamboo shoots and exploding them to scare off evil spirits.

Last July 4, when Flickr member m01229 captured this image, she was just one of 500,000 who were thrilled by seeing 33 tons of well-timed, expensive explosions over Washington, DC.

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