Photography of any kind was still a relatively new technology in 1895—imagine what it must have felt like to learn you could take a photograph of a living person’s bones.
On this day in 1895, scientist Wilhelm Conrad Röntgen published a paper called ‘On a New Kind of Rays.’ It was the first scientific paper to describe x-rays. Only six days earlier, he took the x-ray that was published with the paper: his wife’s hand, her wedding ring visible on the fourth finger. Although we don’t think about it much now, the x-ray gave people an entirely new ability: to see inside a living person without cutting them open first.
The English translation of Röntgen's paper appeared in the January 23, 1896 edition of Nature. He describes conducting an experiment by firing electricity through a vacuum tube. He’d covered the tube in black cardboard to block the light this produced, but even though the tube was covered he noticed that a fluorescent screen more than a meter away was glowing, writes Hannah Waters for The Scientist. (One of the earliest x-ray tubes is in the collection of The National Museum of American History.)
Röntgen dubbed these mysterious rays capable of passing through glass “X” (for unknown) and subsequently tried to block them with a variety of materials—aluminum, copper, even the walls of his lab—to no avail,” she writes. When he tried it with a piece of lead, she writes, it blocked the rays, “but he was shocked to see his own flesh glowing around his bones on the fluorescent screen behind his hand.” The step from here to an x-ray photograph was short.
The ability of the new rays to image the bones within a living hand interested the general public for some six months,” writes researcher Arne Hessenbruch. Newspapers published long explorations of how the x-ray worked and what its consequences might be, while humorists produced cartoons and theaters wrote x-ray plays. The prospect of total nakedness, as shown by early x-rays of hands, was understandably titillating to the general public.
But while the public was laughing, the x-ray was immediately useful to doctors. The first x-ray machine was used to take images of patients just a month after the publication of Röntgen's paper, reports one 2011 study. Within just a few months, it was being used by battlefield doctors, writes Dan Schlenoff for Scientific American. Before the x-ray, there was no reliable way to tell precisely what was going on inside someone’s body. The exact location of a break in a bone, a bullet, or a piece of shrapnel was a mystery.
Over the next few years, Schlenoff writes, they were used in the Greco-Turkish War, the Russo-Japanese War and the Balkan Wars. “Mobile units were developed to keep up with field hospitals,” he writes. “If surgery could be performed, x-rays became vital.” By the time WWI began, x-ray technology was well-established.
Civilian doctors were as quick to see the technology’s usefulness. “Within a year, the first radiology department opened in a Glasgow hospital,” Waters writes, “and the department head produced the first pictures of a kidney stone and a penny lodged in a child’s throat.”
X-rays are light, like any other light, but they’re not in the visible spectrum. And their properties meant that early x-rays were very damaging to people’s bodies. Barely two weeks after Rӧntgen’s discovery, a dentist used himself as a guinea pig and shot the first dental radiograph, write K. Sansare, V. Khanna and F. Karjodkar in the journal DentoMaxilloFacial Radiology. The exposure took 25 minutes, which he later described as torture, although he didn’t elaborate. But he continued to experiment with radiation—on his patients, not himself.
Many other early medical uses of x-rays resulted in patients getting burns. A 2011 study of an early x-ray machine found that its use would expose the skin to 1,500 times the amount of radiation present in a modern x-ray.