A wild leopard runs on the stairs as it tries to escape from a compound of a house in Kathmandu, Nepal June 1, 2016. (Photo by Navesh Chitrakar/Reuters)

Detainees look out from a prison cell at a compound of the Lukyanivska detention centre in Kiev, Ukraine, July 19, 2016. (Photo by Valentyn Ogirenko/Reuters)

Gloria Grahame in state of undress in a scene from the film “Naked Alibi”, 1954. (Photo by Universal/Getty Images)

An incredible clear-air lightning display from storms to the east of Noonamah, just outside Darwin on April 6, 2015. (Photo by Jacci Ingham/The Guardian)

American rapper from Memphis GloRilla attends the Billboard Women in Music Awards in Inglewood, California on March 7, 2024. (Photo by Mario Anzuoni/Reuters)

A pedestrian holds an umbrella to protect from the sun in Bangkok, Thailand, Friday, May 3, 2024. (Photo by Sakchai Lalit/AP Photo)

People jump into a swimming pool seeking relief from the summer heat, in Sanaa, Yemen on August 7, 2025. (Photo by Khaled Abdullah/Reuters)

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.