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.

Отава Ё – Яблочко (Otava Yo – Yablochko; Russian: Яблочко, “Little Apple”). Yablochko is a Russian folk song of chastushka style and dance, traditionally presented as sailors' dance. The choreographed version of the dance first appeared in the 1926 Reinhold Glière ballet The Red Poppy and from there is known in the West as the Russian Sailors Dance.

A visitor takes a selfie with “The Breach” by Leandro Erlich, during a photo call for Kew Gardens' forthcoming “Food Forever” exhibition, examining the fragile future of food and the impact of our day-to-day eating habits on the planet, at the Royal Botanic Gardens, in Kew, Richmond, Surrey on Thursday, June 16, 2022. (Photo by Dominic Lipinski/PA Images via Getty Images)

A leopard attacks an Indian man as others climb a wall to get away from the animal in Lamba Pind area in Jalandhar on January 31, 2019. After a leopard was spotted in a house in Lamba Pind area of Jalandhar city, subsequent attempts to capture it led to the animal attacking at least six people, though none was injured seriously, local media said. (Photo by Shammi Mehra/AFP Photo)

A ten-week-old North China leopard (Panthera pardus japonensis) is handled during a routine health check in the Zoo of Debrecen, northeastern Hungary, 30 January 2024. The female cub, which was born on 21 November 2023, belongs to a leopard subspecies that is endemic to the forest habitats of Northern China. (Photo by Zsolt Czegledi/EPA/EFE)

Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

A guide dangles a live chicken in front of a crocodile in the village of Bazoule, Burkina Faso, December 4, 2015. The villagers believe the crocodiles that live there are sacred. (Photo by Joe Penney/Reuters)