Pham Thi Thanh drinks a glass of water used as a treatment during a medium ritual at a Hau Dong ceremony at Phu Day temple in Nam Dinh province, Vietnam, May 7, 2017. Dating to the 16th century, Hau Dong centres on a belief in the Mother Goddesses of three realms – forest, water and heaven. It draws from elements of Taoism, Buddhism and other religions. (Photo by Reuters/Kham)

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.

A 20 metre high spiral staircase in a tower used as an emergency exit, is seen inside a Federal Reserve bank (Bundesbank) bunker, prior to the bunker's official opening to the public in Cochem, Germany, March 18, 2016. West Germany's Central Bank (Deutsche Bundesbank) stored some 20 billion German marks of emergency notes in two underground bunkers, one in Frankfurt the other in Cochem, between 1964-1988 during the cold war. (Photo by Kai Pfaffenbach/Reuters)

The Moonlight Rainbow Fountain is the world's longest bridge fountain that set a Guinness World Record with nearly 10,000 LED nozzles that run along both sides that is 1,140m long, shooting out 190 tons of water per minute. Installed in September 2009 on the Banpo Bridge, former mayor of Seoul Oh Se-hoon declared that the bridge will further beautify the city and showcase Seoul's eco-friendliness, as the water is pumped directly from the river itself and continuously recycled. The bridge has 38 water pumps and 380 nozzles on either side, which draw 190 tons of water per minute from the river 20 meters below the deck, and shoots as far as 43 meters horizontally.

A Russian Orthodox believers dips in the icy water during a traditional Epiphany celebration in St. Petersburg, Russia, Wednesday, January 19, 2022. Thousands of Russian Orthodox Church followers plunged into icy rivers and ponds across the country to mark Epiphany, cleansing themselves with water deemed holy for the day. The temperature in St. Petersburg is –1C (30F). (Photo by Dmitri Lovetsky/AP Photo)

Scuba divers during an ice diving class at the Sea Frogs scuba diving center in the Russian Far Eastern city of Vladivostok on January 30, 2022. The air temperature is –11°C (12.2°F), the water temperature is –2°C (28.4°F). Scuba divers undergo theoretical and practical training in ice diving and perform dives in the open water during the day and the night time as part of the Ice Diver NDL special program. (Photo by Yuri Smityuk/TASS)

Egrets stand on a field as an Egyptian farmer plants rice seedling in Egypt's fertile Delta in Tanta, Algharbeya governorate, 100 km from Cairo, Egypt, 22 June 2022. Egyptian Government reduced the planting of some crops that need a massive amount of irrigation water, while the government said it will reduce the rice agriculture area in Egypt, amid fear the Renaissance Dam project in Ethiopia could affect the amount of River Nile water reaching Egypt. (Photo by Khaled Elfiqi/EPA/EFE)

Believers bathe in the icy water during a traditional Epiphany at the Church of the Holy Trinity in Ostankino near TV Tower in Moscow, Russia, Wednesday, January 18, 2023. Across Russia, the devout and the daring are observing the Orthodox Christian feast day of Epiphany by immersing themselves in frigid water through holes cut through the ice of lakes and rivers. Epiphany celebrates the revelation of Jesus Christ as the incarnation of God through his baptism in the River Jordan. (Photo by Alexander Zemlianichenko/AP Photo)