Polonium the Curies while they were investigating the cause of pitchblende radioactivity. Pitchblende, after removal of the radioactive elements uranium and thorium, was more radioactive than the uranium and thorium combined. This spurred the Curies to search for additional radioactive elements. They first separated out polonium from pitchblende in July 1898, and five months later, also isolated radium. German scientist Willy Marckwald successfully isolated 3 milligrams of polonium in 1902, though at the time he believed it was a new element, which he dubbed "radio-tellurium", and it was not until 1905 that it was demonstrated to be the same as polonium.
Discover the Networks Discover the Networks Discover the Networks (originally Discover the Network) (DtN) is a website run by the David Horowitz Freedom Center that focuses on the individuals, groups, and history of groups alleged to be politically left wing. DtN was launched in 2004 and has a staff of about a dozen contributors. Its current Editor-in-Chief is David Horowitz; John Perazzo is the project's managing editor, and Richard Poe is its investigative editor. Discover the Networks is associated with FrontPageMag.com. According to the project's mission statement, DtN's goal is to provide a comprehensive "guide to the political left" covering "the individuals and