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 woman poses for a photo at Hitchin Lavender farm in Ickleford, Britain, August 4, 2020. (Photo by Peter Cziborra/Reuters)

Tourists dressed in yukatas, a light, unlined, summer kimono made of cotton instead of the traditional silk, climb steps to visit a temple on April 27, 2016 in Kyoto, Japan. Now the seventh largest city in Japan, Kyoto was once the Imperial capital for more than one thousand years, it is now the capital city of Kyoto Prefecture and a major part of the Kyoto-Osaka-Kobe metropolitan area. (Photo by Carl Court/Getty Images)

Mount Whaleback iron ore mine 23°21’32.3”S, 119°40’40.1”E. The Mount Whaleback Iron Ore Mine in the Pilbara region of Western Australia. Roughly 98% of the world’s mined iron ore is used to make steel and is thus a significant component in the construction of buildings, automobiles, and appliances such as refrigerators. (Photo by Daily Overview/DigitalGlobe, a Maxar Company)

Lord Roscoe the cat runs through the crocuses on the lawns at the National Trust's 17th-century Ham House and Garden in Richmond, London on Monday, March 6, 2023. In recent years more than 500,000 bulbs have been planted to create a spectacle for visitors and to attract bees, butterflies and other pollinating insects. (Photo by Kirsty O'Connor/PA Images via Getty Images)

Performing arts titled “Solitude of Silences” by Gimhongsok is staged at Art Basel in Hong Kong, China on March 23, 2023. (Photo by Tyrone Siu/Reuters)

An osprey flies with a fish in its talons at the Sebastian Inlet State Park in Melbourne Beach, Florida on April 1, 2025. (Photo by Ronen Tivony/ZUMA Press Wire/Rex Features/Shutterstock)