Radioactive substances spontaneously emit rays that are similar to X-rays, however these rays are generated from the actual substances. These continual emissions can last for months at a time without outside assistance. An example of these natural substances are Uranium and radium, they are found in small quantities throughout the interior of the earth.
Soon after the discovery of the X-ray, Henry Becquerel the effects of radioactive substances in 1896. When uranium salts affected a photographic plate without any assistance of a fluorescent light, the rays emitted from the radioactive subs…