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.

Gertrude “Billie” Murphy, 22, is brought in for questioning in the murder case of Michael Stopec, who was shot and killed in an apartment hotel, circa July 1927. Murphy had been friends of the married Stopec and his suspected killer Henry Guardino, 31. It is said that Stopec and Guardino were “bitter rivals for the favor of Billie” and that Murphy had tired of Guardino and was going to stay with Stopec. Murphy was also married to a man in the Joliet penitentiary. (Photo by Chicago Herald & Examiner Historical Photo)

The moon illuminates the snow-covered Concordia, the confluence of the Baltoro and Godwin-Austen glaciers, near the world's second highest mountain the K2 (8,000 meters) in the Karakoram mountain range in Pakistan September 6, 2014. While other parts of Pakistan and northern India were flooded, Concordia in the Karakoram mountain range was covered with a seasonally unusual amount of snow. Geographically, Pakistan is a climbers paradise. It rivals Nepal for the number of peaks over 7,000 meters and is home to the world's second tallest mountain, K2, as well as four of the world's 14 summits higher than 8,000 meters. (Photo by Wolfgang Rattay/Reuters)

Afghan militia men stand near to the dead body of a beheaded Islamic State group loyalist in the Achin district of Nangarhar province east of Kabul, Afghanistan, Sunday, December 27, 2015. An Afghan official says fighters for the Islamic State group and a militia controlled by a prominent lawmaker have beheaded a total of eight men in tit-for-tat revenge killings in the eastern border province of Nangarhar. (Photo by Mohammad Anwar Danishyar/AP Photo)

In this December 23, 2013 photo, Indian army soldiers patrol near one of their forward post at the Line of Control (LOC), that divides Kashmir between India and Pakistan, at Krishna Ghati (KG Sector) in Poonch, 290 kilometers (180 miles) from Jammu, India. The military commanders of longtime rivals India and Pakistan met on Tuesday in a bid to stop frequent cross-border attacks in disputed Kashmir which escalated tensions in the region in recent months. (Photo by Channi Anand/AP Photo)

Senator Barack Obama (D-IL) (R) stands in front of Senator Hillary Clinton (D-NY) as they arrive for U.S. President George W. Bush's annual State of the Union speech to a joint session of Congress at the U.S. Capitol in Washington in this January 23, 2007 file photo. Hillary Clinton announced her second run for the presidency on April 12, 2015 starting her campaign as the Democrats' best hope of fending off a crowded field of lesser-known Republican rivals and retaining the White House. (Photo by Larry Downing/Reuters)

A burning flame and a broad expanse of water are among the few things which do not tire us with their beauty. However, while we have many sources of water around us, it is quite hard to marvel at a burning flame on a daily basis. Melissa Crisp is one of the few people who were able to subdue the element of fire. She is the person who is behind the design of the uniquely-shaped fire pits, which feature mystifying themes, including a pair of lovers, a fire on the rodeo arena, a forest fire, a fiery flower, and a number of others. Each of the fire pits entrances you, and it almost seems like the characters are alive, as the hot fire burns deep within the spheres, casting dancing shadows all around. (Photo by Melissa Crisp)

Two women react to the camera as Nightclub Circus hosts the first dance event, which will welcome 6,000 clubbers to the city's Bramley-Moore Dock warehouse on April 30, 2021 in Liverpool, England. The event is part of the national Events Research Programme which will provide data on how events could be permitted to safely reopen. (Photo by Anthony Devlin/Getty Images)