9781422279465

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Helium

discovery. Time passed, and helium was still not found on Earth. Some began to doubt the research that Janssen and Lockyer had done. That all changed a few decades later in 1882, when the Italian physicist and meteorologist Luigi Palmieri was studying the historic eruptions of volcanoes in Italy. While studying the gases seeping from Mt. Vesuvius, he identified that same yellow spectral line—the line of the element named helium. Then, in 1889, the American chemist William Hillebrand was ex- perimenting with the mineral uraninite, which is composed of urani-

um and oxygen. He found that as uraninite dis- solves in sulfuric acid, it releases an inert gas. He thought at the time that the inert gas was nitrogen, and while a portion of that gas was ni- trogen, there was another gas involved. Further research by the Scottish chemist William Ramsay proved that the inert gas from the dissolving uranium-rich mineral was in fact helium. Ramsay repeated Hillebrand’s experi- ment using another mineral composed of ura-

William Hillebrand

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