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.

From left, Cierra Fraser, 28, Los Angeles, a nanny, and Joslin Farley, 28, Los Angeles, a barista, poses in the outfits they wore to see the movie “Barbie” at TCL Chinese Theater in Los Angeles, California, on July 22, 2023. “I just knew that it was in good hands. I knew we were not gonna get a stereotypical barbie movie. I knew it was gonna be exactly what the people needed”, said Farley. (Photo by Jenna Schoenefeld for The Washington Post)

Dublin student beat depression by befriending sharks, stingrays and pigs in the Bahamas. Awesome underwater pictures show the 23-year-old diver cosying up to a range of animals including turtles, stingray and sharks. The sunny selfies were taken in the Bahamas by Stuart’s Cove dive instructor and native of the island, Amelia Klonaris – who beat depression by embracing her incredible beach paradise lifestyle. (Photo by Amelia Klonaris/Mediadrumworld)

Grade 5 student Lovely Joy De Castro, 11, takes notes while attending an online class using a smartphone, as schools remain closed during the Coronavirus disease (COVID-19) outbreak, at Manila South Cemetery where she lives with her family in Makati City, Philippines, November 6, 2020. (Photo by Eloisa Lopez/Reuters)

A guest proposes to his companion as they arrive for the screening of “Mektoub, My Love: Intermezzo” during the 72nd annual Cannes Film Festival, in Cannes, France, 23 May 2019. The movie is presented in the Official Competition of the festival which runs from 14 to 25 May. (Photo by Julien Warnand/EPA/EFE)

People take part in a Halloween street party at Lan Kwai Fong on October 31, 2016 in Hong Kong. Halloween, a contraction of All Hallows' Evening, falls on the day before All Saints' Day on November 1, a holiday when Christians remember their deceased loved ones. (Photo by Lam Yik Fei/Getty Images)

Participants of the techno-parade “Zug der Liebe” (Train of love) dance on a street in Berlin, Germany July 25, 2015. The “Zug der Liebe” is the successor to the “Loveparade”, which in its heyday attracted up to 100,000 participants and ended in disaster and tragedy in 2010 when 21 people died and over 500 were injured due to suffocation from overcrowding at the “Loveparade” in Duisburg. (Photo by Axel Schmidt/Reuters)