Polonium in the Earth's crust are not harmful. Polonium has been found in tobacco smoke from tobacco leaves grown with phosphate fertilizers. Because it is present in small concentrations, isolation of polonium from natural sources is a tedious process. The largest batch of the element ever extracted, performed in the first half of the 20th century, contained only (9 mg) of polonium-210 and was obtained by processing 37 tonnes of residues from radium production. Polonium is now usually obtained by irradiating bismuth with high-energy neutrons or protons. In 1934, an experiment showed that when natural Bi is bombarded with neutrons, Bi
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