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 stranded cat swims through flood water searching for dry land June 16, 2008 in Oakville, Iowa. (Photo by Scott Olson/Getty Images)

A mahout splashes water on his elephant in the river Sabarmati on a hot summer day in Ahmedabad, India, May 20, 2015. (Photo by Amit Dave/Reuters)

A man drinks at a "colored" water cooler in a streetcar terminal in Oklahoma City, July 1939. (Photo by Reuters/Library of Congress)

A mahout splashes water on his elephant on a hot summer day in Ahmedabad, India on April 8, 2019. (Photo by Amit Dave/Reuters)

The performers prepare for the show. Fontana, a travelling water circus produced by Cirque Du Liban at Festival City in Dubai. (Photo by Chris Whiteoak/The National)

People use large water guns to spray each other as they celebrate the annual Songkran festival in Bangkok, Thailand on April 14, 2025. Thailand celebrated the Thai traditional New Year, called Songkran in Thai and also known as ëthe water festivalí, on 13 April, with festivities going on on throughout the weekend. During Songkran, people celebrate the New Year by splashing water to each other as a sign of washing away sins and bad luck from the previous year. People across Thailand celebrate the New Year with parties and water related activities throughout the weekend. (Photo by Diego Azubel/Matrix Images)

Two daredevil photographers have risked their lives to become the first people to capture the explosive moment fiery lava crashes into the sea – while in the water themselves. Fearless duo Nick Selway, 28, and pal CJ Kale, 35, brave baking hot 110F (43,3C) waters to snap the amazing images – standing just feet away from scalding heat and floating lava bombs. Using a simple protective casing around their cameras, and donning just swimming shorts and flippers, they bob up and down with the water as the surf washes over their heads. (Photo by Nick Selway/CJ Kale/Caters News Agency)