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.

“The Tibetan Mastiff also known as Do-khyi (variously translated as “home guard”, “door guard”, “dog which may be tied”, “dog which may be kept”), reflects its use as a guardian of herds, flocks, tents, villages, monasteries, and palaces, much as the old English ban-dog (also meaning tied dog) was a dog tied outside the home as a guardian. However, in nomad camps and in villages, the Do-khyi is traditionally allowed to run loose at night and woe be unto the stranger who walks abroad after dark”. – Wikipedia

Photo: A man displays a Tibetan Mastiff he raised during the Tibetan Mastiff exposition on April 7, 2007 in Langfang of Hebei Province, China. (Photo by China Photos/Getty Images)

“Echus Chasma is a chasma in the Lunae Planum high plateau north of the Valles Marineris canyon system of Mars. Clay has been found in Echus Chasma that means that water once sat there for a time. Echus Chasma is approximately 100 km long and 10 km wide, with valleys ranging in depth from around 1 km to 4 km”. – Wikipedia

Photo: In this handout image supplied by the European Space Agency (ESA) on July 16, 2008, The Echus Chasma, one of the largest water source regions on Mars, is pictured from ESA's Mars Express. The data was acquired on September 25, 2005. The dark material shows a network of light-coloured, incised valleys that look similar to drainage networks known on Earth. It is still debated whether the valleys originate from precipitation, groundwater springs or liquid or magma flows on the surface. (Photo by ESA via Getty Images)

The close-up of the Pecteilis radiata is very reminiscent of a beautiful white bird soaring in the skies. This is probably the reason why people have started calling this flower the White Egret Flower. Truly, the resemblance of this flower to an egret flying through heavens is staggering. It is too bad that these flowers are so small. Otherwise, they would make for a stunning bouquet. However, who wouldn’t want to receive such a precious flower as a gift; a flower which can be used as a symbol for beauty, good intentions, and the purity of soul. (Photo by AngiBudd)

Head of European Prints, Severine Nackers holds a celestial Map of the Southern Sky by Albrecht Durer, at Sotheby's Auction House on March 25, 2011 in London, England. The two woodcut maps depicting the Northern and Southern skies circa 1515, are the earliest printed star charts of their kind ever published in Europe, and are expected to fetch between Ј120,000-180,000 GBP when they go on sale at the “London sale of Old Master, Modern and Contemporary prints” at Sotheby's Auction house on March 30, 2011. (Photo by Dan Kitwood/Getty Images)

International artist Yvette Mattern shows her stunning laser rainbow projection, Global Rainbow, on March 1, 2012 in Whitley Bay, England. The light installation celebrates the London 2012 Cultural Olympiad in the north-east of England. The Global Rainbow has previously lit up the skies of Germany, France and the United States. The projection will shine along the North Tyneside coastline for 4 days, before moving to other locations in the UK. (Photo by Bethany Clarke/Getty Images)

In his book “Side Effects”, aerial photographer Kacper Kowalski took to the skies to paint a portrait of the complex relationship between humans and nature. From the sky, he captured where nature and civilization collide into aesthetic, abstract colors and shapes. Photo: A view over fields of grain in Spring chamomile, cornflower and other weeds growing amongst the grain sprouts. (Photo by Kacper Kowalski/Panos Pictures)

Photographer Brian Finke spent nearly two years traversing the friendly skies, following the life of flight attendants in the air and on the ground, from Delta and Hawaiian Air, to Hooters Air, Southwest, Air France, British Airways, Air Asia, and dozens more. His images of flight attendants waving, applying makeup and deboarding plans while smiling appear as if they were ripped from an advertisement in a glossy magazine. Here: Tiger Airways, Singapore, 2006. (Photo by Brian Finke/The Washington Post)