A worker sings while carrying prickly pears on his head as their production is on the rise due to low water consumption and ability to withstand extreme temperatures, according to farmers, at a farm in Al Qalyubia Governorate, Egypt on August 2, 2022. (Photo by Mohamed Abd El Ghany/Reuters)

A tourist pets a cat before the “Horus protects Ramses II as a child”, dating to the reign of the Ancient Egyptian New Kingdom pharaoh (1303-1213 BC), at the Egyptian Museum in the centre of Egypt's capital Cairo on October 19, 2022. (Photo by Amir Makar/AFP Photo)

A prong extending from a remote-controlled robot prototype approaches the mouth of a volunteer to extract a throat swab sample, as part of a self-funded project to assist physicians in running tests on suspected COVID-19 coronavirus patients in a bid to limit human exposure to disease-carriers, at a private hospital in Egypt's Nile delta city of Tanta, on March 20, 2021. (Photo by Khaled Desouki/AFP Photo)

An Egyptian boy rides his donkey in front of a cafeteria with a picture of former Barcelona's forward player Lionel Messi at a village, near Giza, on the outskirts of Cairo, Egypt, February 7, 2022. (Photo by Amr Abdallah Dalsh/Reuters)

Divers watch as a crane pulls a piece of stone from the waters at Abu Qir bay in Alexandria on August 21, 2025, as part of an event organized by the Ministry of Tourism and Antiquities to recover sunken antiquities. (Photo by Khaled Desouki/AFP Photo)

An Egyptian university student drives a hybrid racing car he built with his team to compete at the Global Hybrid-Electric Challenge in Cairo, Egypt September 2, 2016. (Photo by Mohamed Abd El Ghany/Reuters)

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.