The following year, Henri Becquerel discovered that a piece of the ore pitchblend caused a photographic plate to be exposed, even when the pitchblend was wrapped in paper or tin foil (remember, aluminum was very new and terribly expensive at this time.) Although this discovery was greeted with a good bit of skepticism at the time, Becquerel convinced Pierre and Marie Curie to undertake the separation of the active materials from the pitchblend. Becquerel and the Curies shared the 1903 Nobel Prize.
At this time there was no understanding of the dangers of handling highly radioactive materials, and the Curie's hands became burned and scared by the radiation. The Curie's laboratory was little more than a shed near Marie's original storeroom laboratory. It leaked, had poor ventilation (perhaps a good thing as it allowed the radon to escape into the air) and was miserably cold in the winter. Dispite the discomforts, the result of this work was glorious to the Curie's and Marie describes her excitement in the following way:
"One of our joys was to go into our workroom at night, we then perceived on all sides the feebly luminous silouettes of the bottles or capsules containing our products. It was a lovely sight and always new to us. The glowing tubes looked like faint fairy lights."
The Curie's and Ernst Rutherford who had been a research student working for J. J. Thompson, and was at this time a professor at McGill University in Montreal, Canada, corresponded a great deal and the samples of radium used by Rutherford came from the Curie's. Working separately they established that there appeared to be three kinds of rays emitted by the radioactive samples, as determined by how the rays responded to a magnetic field. This experiment, a modification of Thompson's experiment, placed a sample of radium (or an impure sample containing radium and other radioactive materials) in a vacuum tube identical to a Crookes tube except that it didn't have a cathode or anode. The radium was the source of the rays. When a magnet was placed around the tube along the path the rays had to travel, it was found that one set of rays was unaffected by the field (later called gamma rays), while a second set bent in one direction and yet a third set bent in the other direction. Later work established that one of the rays (called beta rays by Rutherford) behaved exactly like cathode rays while a second set (alpha rays) appared to be positively charged and much heavier (based on their curvature in the field) than the beta rays.
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