A small pile of powder on a heat-resistant surface and a flame, that’s all it takes to create this experiment. Slowly but surely, the powder starts to smolder. At first, there’s only a wisp of smoke, but then something almost magical happens: from the powder, a strange, snake-like structure begins to grow. It twists and turns as it extends upward, slithering in slow-motion coils. As it continues to grow, the ash becomes long and snake-like, giving the illusion of a serpent rising from the ground. Of course, there’s no magic involved — just chemistry. What you’re seeing is basically a very expa…