Ueber eine neue art von strahlen
1895
Wilhelm Conrad Röntgen(1845-1923)
 In the autumn of 1895, Roentgen, a professor of physics at Wurtzburg University carried out experiments on cathode rays with a crooks tube. While he was investigating the fluorescent action of cathode rays, he accidentally discovered that a paper coated with barium-platinocyanide was fluoresced, although the paper was placed two meters apart from the paper covered tube. He thought that this fluorescence was caused not by cathode rays, which could penetrate the paper, but by an unknown penetrative radiation which was excited by the cathode rays on the glass wall of the tube. He called this radiation X-rays. Roentgen repeated the experiments for seven weeks and confirmed the fundamental qualities of X-rays.
 The papers above were Roentgen’s first and second announcements of this discovery which were made in lectures. In the second lecture he demonstrated by taking X-rays of the hand of Kolliker, his colleague and a famous anatomist. These reports and the picture caused a world-wide sensation in the scientific world. It was a great discovery that became useful for various applications, particularly medicine, and also initiated a new realm in physics, called radiological science.