If we were to burn NH4Cr2O7 with HgSCN in the Dark Ages in Europe and show it to anyone, it is us who would be burning next on a fiery cross of Inquisition. And it’s no wonder, since this experiment produces a truly marvelous result. At first, as you ignite the mixture of NH4Cr2O7 and HgSCN, all you can see is that it is slowly burning with a reddish flame. After a while, however, a crater is formed in the middle of the burning pile, and then, suddenly, tentacle-like appendages start sprouting from the burning mixture. And you can almost hear the scream of the mad occultist – “Come forth, Kraken! Come forth!” But of course, this is simply a chemical reaction that is called the "Pharoah's Serpent". It was also often sold in firework stores until people realized that it was toxic.

A gilrl plays games in a shopping mall in Beijing, China, 24 November 2021. Demographers in China have called for more efficient implementation of supportive measures to encourage births to address the country's dwindling population growth as country's birthrate last year was 8.52 births per thousand people, the lowest level since 1978, according China Statistical Yearbook 2021. (Photo by Wu Hong/EPA/EFE)

A model backstage ahead of the Rasit Bagzibagli show during Mercedes-Benz Fashion Week Istanbul at on March 27, 2018 in Istanbul, Turkey. (Photo by Sinem Yazici/Getty Images for IMG)

A child dressed as an Ewok character participates in a Star Wars parade in Mexico City, Saturday, October 15, 2022. (Photo by Marco Ugarte/AP Photo)

A rider picks up a hada, a traditional Tibetan ceremonial scarf, during a horse racing event of the 18th Mount Qomolangma culture and tourism festival in Xigaze, southwest China's Tibet Autonomous Region on June 20, 2023. (Photo by Sun Fei/Xinhua News Agency/Alamy Live News)

Russian riot policemen beat young PREGNANT female anti-Putin activist during a protest rally against the Presidential inauguration of Vladimir Putin on May 6, 2012 in Moscow, Russia.

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