November is known for turkey and football, but it also marks the anniversary of a discovery that changed medical technology forever. During this month in 1895, Wilhelm Conrad Röntgen (Rent-GEN) became the first person to discover X-rays, an advance that made the invisible visible and changed the world of medicine forever.

Before the advent of X-ray machines, doctors could only find out what was wrong inside their patient’s bodies by opening them up in surgery.

Röntgen’s discovery occurred accidentally in Germany while he was studying the path of electrical rays through a glass tube. He noticed that these newly found X-rays could penetrate a number of objects, including human flesh. He then realized he could project images showing the contrast between the bones in the body and the transparent skin.

In the first 20 years following Röntgen’s discovery, X-rays were used to treat soldiers wounded in battle. The new technology allowed doctors to find bone fractures and bullets. The downside was that scientists were somewhat slow to realize X-rays had harmful side effects, too.

Major John Hall-Edwards took one of the first radiographs for an operation in February 1896. However, in 1908, he had to have his left arm amputated due to the constant exposure to these harmful rays.

Since then, doctors have taken measures to protect people from the damaging effects of radiation. Soon came the discovery of tomography, which can show a single slice of the body on film. In the 1970s, the first C-T system, also called a CAT scan, was created.

Without Röntgen’s discovery, medical practice could still be in the dark ages. Secrets of the body were revealed because of this lucky accident. Imagine detecting cancer or deciding between a fracture or a sprain without these images. Where would we be without the X-ray?