X-Rays
While testing whether cathode rays could pass through glass, in 1895, a Professor of Physics in Wurzburg, Bavaria, would inadvertently discover a new type of ray. They would be dubbed ‘X’ rays (as in X for unknown), despite the man who discovered them, Wilhelm Röntgen, really hoping they would be named ‘Röntgen Rays’ (although a few countries do still use that name) in honor of him.
When Röntgen covered the cathode tube he was experimenting with heavy black paper so that the visible light from the tube would not interfere, he was shocked to see an incandescent green light escaping from the tube and being projected on a fluorescent screen about 1 meter away.
After a few experiments he quickly learned that this mysterious light would pass through most substances and leave a shadow of the solid object. He would soon discover that these ‘X-Rays’ would pass through human tissue too, rendering the bones and tissue beneath visible.
News of this amazing discovery was quick to spread around the world and within only one year doctors across Europe and in the United States were using X-rays to locate gun shots, bone fractures, kidney stones and swallowed objects. For his efforts, Röntgen would be awarded the first ever Nobel Prize for Physics in 1901.