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.

Looking for a reason to visit the Philippines? This mermaid school should do the trick. No, seriously, there’s an actual school that will teach you how to be a mermaid. It’s called the Philippines Mermaid Swimming Academy. (Photo by Philippine Mermaid Swimming Academy/Exclusivepix Media)

My name is Jakub and I’m a painter, illustrator & concept artist who lives and work in Poland. My speciality is dark fantasy, character design, concept art and portrait. Since several years I work and paint digitally, but I never gave up traditional drawing and painting. For me the most important in my work, is create unique atmosphere and tell some kind of story through my creations.

Photographer Han Youngsoo captured the ordinary people of Korea as the country emerged from war into an age of prosperity. Han Youngsoo: Photographs of Seoul 1956–63 is at the International Center of Photography (ICP), Jersey City, New Jersey, until June 9, 2017. Here: Seoul, Korea. (Photo by Han Youngsoo/The Guardian)

Sprout A Pencil That Grows is a very simple but excellent concept. We all know that as soon as a pencil gets down to the point where there’s only an inch or so left it’s pretty much useless. The Sprout lets you put that little stub to get use. The end of the Sprout has a seed capsule that is water activated, after you plant your pencil and water it a few times the capsule dissolves and the seed’s start germinating. The plants usually take about a week to sprout. The Sprout pencils come in a number of varieties including vegetables, herbs and flowers like rosemary, tomato, marigold, and many more.

Suso33 spent the last few days perched on a yellow crane to work on this impressive new piece on the streets of Madrid, Spain. Using a rather simple technique, the Spanish artist painted a brilliant piece which enters directly amongst our favourite artworks this year. This mural is a concentration of slightly outlined figures which are persecuted by their shadows, but if the viewer, instead of focusing on details, looks at the entire picture, what he sees is another figure. Take a look at more images after the jump and if you are in the area, you'll be able to find the piece at plaza del Poeta Leopoldo de Luis.

Watermelons are one of the sweetest parts of summer, but there’s no reason not to have some fun with them before you start eating. Artist Clive Cooper of Sparksfly Design saw beauty in the rinds and got to work carving sculptures out of the fruit before digging in. (Photo by Clive Cooper)