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.

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Hundreds of volunteers stand at Goma International Airport receiving instructions before boarding a plane that will take them to a training center after responding to Democratic Republic of Congo's President Felix Tshisekedi's call to join the army to go to the front lines to fight against the M23 rebellion (March 23 Movement) in Goma, Democratic Republic of Congo, on November 14, 2022. (Photo by Guerchom Ndebo/AFP Photo)