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.

Crowds on the beach in Cape Canaveral, Fla., watch the launch of the SpaceX Falcon 9 Crew Dragon on its Crew-1 mission carrying four astronauts, Sunday, November 15, 2020, in this 3 1/2-minute time exposure. The rocket was launched from Launch Complex 39A at Kennedy Space Center at 7:27 p.m. Sunday evening. (Photo by Malcolm Denemark/Florida Today via AP Photo)