Then, on 26 December, they announced the discovery of a second new element: radium. But it still didn’t explain all of the radiation seen in pitchblende. That July, the couple announced the discovery of the element polonium, which they named after Marie’s native Poland. Two years earlier Henri Becquerel had discovered that uranium salts gave off rays that could penetrate objects in a similar way to the newly discovered X rays, but Marie had noticed that pitchblende gave off much more of what she later called radioactivity than would be expected if uranium alone was to blame.Įxcited by Marie’s work, Pierre stopped his own research into crystals to help her grind down tonnes of the mineral in search of an answer. Marie had been investigating the unusual properties of pitchblende, a black mineral that is rich in uranium. More than 100 years after their discoveries, the couple’s notebooks are still so radioactive they have to be kept in lead-lined boxes and handled only while wearing protective clothing.ġ898 was a busy year for the couple. Marie even kept vials of what she was working on in her pockets or her desk drawers. At the time no one knew about the effects of radioactivity on the body, so they handled the elements they used in their research without any of the precautions or protective clothing we would use today. The couple set up a joint laboratory in a basement, building their own equipment for their experiments. There she met Pierre Curie, who worked at the university, and they married in 1895. She also carried out pioneering research into radioactivity.īorn Maria Skłodowska in Warsaw on 7 November 1867, Marie moved to Paris in 1891 to study physics, chemistry and maths at the University of Paris, where she earned two degrees, supporting herself through her studies by tutoring in the evenings. Along with her husband Pierre, she discovered two elements: polonium and radium. "In England by Queen Alexandra, and in Russia by her sister, the Czarina, they both investigating the system while visiting their father, the King of Denmark." There is even a claim that Finsen was able to spare smallpox victims from scarring by keeping them in a room with red glass windows while the disease went through certain stages.Marie Curie was a physicist and chemist who became the first woman to win a Nobel prize. to-day the world rings with his praises." It is claimed that by 1903, Finsen's work was approved of. time Finsen's work received little credence. The book concludes with nine pages concerning the work of Niels R Finsen of Copenhagen who was treating various diseases with light. Ruhmer is also credited with using a seleniun cell to turn off the lights of maritime navigation buoys during daylight hours, thus conserving the gas they burned. It recorded sound rather in the manner of a phonograph, but the sound waves were used, via a selenium cell, to vary the brightness of a beam falling on a moving strip of photographic film. The variation in the light falling on the sensor translated to a varying electrical signal which could be transmitted, then turned back into vibrations in the air.) The photographophone of Ernest Ruhmer is described. A beam of light bounced off the mirror onto a selenium object. (Bell used the sound waves to be transmitted to vibrate a mirror. Use of selenium in a "radiophone" devised by Alexander Graham Bell around 1883 is described. A quantitative measurement of an eclipse of the sun, by means of a selenium based sensor, is reported. There are 21 pages devoted to "The properties and applications of selenium", including the use of its changing electrical resistance in different light levels. Alpha, Beta, Gamma, X-rays, including radiographs of mice made by the latter, and experiments into the lethal effects both of X-rays and of radioactive sources.The work of Pierre and Marie Curie, Dewar, Roentgen, Henri Becquerel, Rutherford, J.In addition to the matters implied by the title of the lecture, ( radium, polonium, actinium, thorium) Hammer discusses such things as:
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