Kekule The Beautiful Dreamer

In 1856, Henri Becquerel was studying the phosphorescence (glowing of certain minerds when exposed to light. In his experiments, he d take a mineral sample, place it on top of a heavily wrapped photographic plate, and expose it to strong sunlight. 

He was preparing to conduct one of these experiments when a cloudy spell hit Paris. Becquerel put a mineral sample on top of the plate and put it in a drawer for safekeeping. Days later, he went ahead and developed the photographic plate and, to his surprise, found the brilliant image of the crystal, even though it hadn t been exposed to light. The mineral sample contained uranium. Becquerel had discovered radioactivity. 

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