Sister Rebecca Leis pours low-gluten alter bread batter into a machine that bakes the thin bread at the Benedictine Sisters of Perpetual Adoration monastery in Clyde, Missouri, December 18, 2014. The Sisters have made communion wafers since 1910 and began making a low-gluten version in 2003 and have gone from 143 customers in 2004 to more than 11,000 customers from around the world. (Photo by Dave Kaup/Reuters)

Women porters load bundles onto their back for transport across the El Tarajal boarder separating Morocco and Spain's North African enclave of Ceuta, in Ceuta on December 4, 2014. Unemployment among Ceuta and Melilla's native workforce is more than 30 percent – among the highest rates in Spain. Meanwhile, authorities say some 30,000 Moroccan traders and menial workers cross into each territory every day. (Photo by Jorge Guerrero/AFP Photo)

Aymara witchdoctor Ricardo Quispe, also called “Lord of the Lake”, throws coca leaves during a ritual to predict the future, at the witches market of El Alto, on the outskirts of La Paz, December 31, 2014. Dozens of witch doctors tend to a warren of stalls in El Alto, making offerings to give thanks, to promise luck at work or in love, or to call up spirits and banish curses at the end of the year. (Photo by David Mercado/Reuters)

Anand Varma, a U.S. photographer working for the National Geographic, won the First Prize in the Nature Category, Stories, of the 2015 World Press Photo contest with his series of pictures, which includes this one of spores of a fungus landing on an ant, penetrating its exoskeleton and entering its brain, compelling the host to leave its normal habitat on the forest floor and scale a nearby tree, in this picture taken January 22, 2014 and released by the World Press Photo on February 12, 2015. (Photo by Anand Varma/Reuters/National Geographic/World Press Photo)

In Mumbai, the windows of new high-rise apartment blocks, old low-rise residential buildings and shantytown shacks portray the disparity in living conditions and incomes in the Indian city. Rents for a place to live range from more than $2,000 to less than $5 a month. Here: Windows and doors of an old residential building are pictured in central Mumbai October 10, 2014. The cost for buying a residential apartment in Mumbai close to the city centre ranges from 12,000 Indian rupees ($ 200) per square feet to 112,552 Indian rupees ($ 1800) per square feet. (Photo by Danish Siddiqui/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.

A boy does a bicycle kick as he practises on the Marina beach ahead of the World Cup soccer tournament in Brazil, in Chennai June 4, 2014. REUTERS/Babu

An old woman looks from inside a car with bullet holes and shattered windows as she flees fighting in the eastern Ukrainian town of Slaviansk June 9, 2014. REUTERS/Gleb Garanich.