By SAURABH JHA and JEANNE ELKIN
Mr. Smith’s pneumonia was clinically shy. He didn’t have a fever. His white blood cells had not increased. The only sign of infection, other than his cough, was that his lung was not as dark as it should be on the x-ray. The radiologist, who learned to see, noticed that the normally sharp border between the heart and the lung was blurred like ink smeared on blotting paper. Something that had colonized the lungs was stopping the x-rays.
One hundred and twenty-five years ago, Wilhelm Conrad Roentgen, German physicist and rector of the University of Wurzburg, made an accidental discovery when he saw something he was not looking at. Roentgen studied cathode rays – invisible forces created by electricity. Using a Crookes tube, a pear-shaped vacuum glass tube with a pair of electrodes, Roentgen pulled the cathode rays from one end with an electric shake. At the other end, the rays would leave the tube through a small hole and generate a colored light on a striking fluorescent material placed near the tube.
By this time, photography and fluorescence had captured the literary and scientific imagination. At Arthur Conan Doyle’s Baskervilles Hound, the fire-breathing dog’s jaw had been soaked in phosphorus by its owner. Electricity and magnetism were the new forces. Physicists were experimenting in backwaters of the electromagnetic spectrum without knowing where they were.
November 8eIn 1895, when after supper Roentgen went to his laboratory for routine experiments, something else caught Roentgen’s eye. Roentgen closed the curtains. He wanted his pupils to be as wide as possible to spot tiny twinkles of light. When he put tension on the Crookes tube, he noticed that a paper soaked in barium platinocyanide on a bench nine feet away was wavering. The cathode rays only traveled a few centimeters. In addition, he had covered the tube with thick cardboard to block the light. Why then was the paper shining?
Roentgen’s scientific ethos was replication. Only the reproducibility of the results could convince him that his eyes were not deceived. The glow was not an artifact because the paper only glowed when the Crooke tube was lit. Had he underestimated the distance traveled by the cathode rays? The paper still glowed when placed further from the tube. Not even a deck of cards stopped the glow.
By the 19th century, physicists had replaced chemists as alchemists of nature. While chemists have tried to convert metal to gold, physicists have created invisible material from invisible material. One of those invisible materials were cathode rays, which then turned out to be electrons. Roentgen did not know their precise nature. He deduced their properties only by careful experimentation. He didn’t think they were responsible for the distant glow. But cathode rays were somehow responsible for this “new kind of rays”, which were similar to light but could penetrate solid material, which he called “x-rays” – the “x” indicating that their nature was. unknown.
X-rays were accidentally discovered because Roentgen accidentally left the fluorescent paper on the remote bench. But they had been discovered because Roentgen was following his pointed observation with a diligent investigation. X-rays could have been discovered earlier if they had been noticed. A few years earlier, Arthur Godspeed, a physicist at the University of Pennsylvania, who also experimented with cathode rays, developed photos, some of which had disc-shaped shadows that were unbeknownst to coins being cast by coins. of change on the x-ray path. William Crookes, the inventor of the Crookes tube, returned several photographic plates to the manufacturers because they were fogged up. After Roentgen’s discovery, he realized that the “damage” he had reported was in fact the x-ray signature.
Roentgen’s laboratory, like Victor Frankenstein’s study, was a Gothic room with devices powered by lightning bolts of electricity. Like Frankenstein, he unleashed science to untangle the supernatural. With curiosity and doubt, Roentgen spent several weeks experimenting with x-rays. He studied the stopping properties of various metals by observing their shadows. Then on one occasion, when he held a piece of lead in his hand, he saw shadows of his bones.
Radiology was conceived on December 22nd, 1895 when Roentgen placed his wife’s left hand in the x-ray path. After a fifteen minute exposure, an iconic photograph emerged. Only bones and a wedding ring cast a shadow. Until then, the bones were only visible when the dead were opened. To see bones stripped of flesh, bare bones, in the living must have seemed supernatural. Six days later, Roentgen published his findings in an article titled “On a New Kind of Rays” in the Proceedings of the Wurzburg Physical Medical Society, a relatively obscure publication with a rapid publication time. Roentgen told Bertha Ludwig, his wife, “now the devil will have to pay.”
January 5e, 1896 the Vienna Press, an Austrian newspaper, published Roentgen’s discovery. Even though there was no social media and only the telegraph shortened distances, news of its discovery went viral. Within ten days, the London Standard and the New York Times ran history. Science disseminated by the media. The medical journals arrived late for the party. The press immediately recognized the medical importance of x-rays, noting that they could photograph broken bones and bullets in human bodies.
The first amateurs of X-rays were photographers, doctors, engineers like Thomas Edison and crooks. X-rays quickly became known for their harmful potential and became antithetical to Victorian sensibilities. An editorial in the Londoner Pall Mall Gazette in March 1896, expressed concern about the “Roentgen rays” and, warning readers of the “revolting indecency” of being able to see people’s bones with the naked eye, asked the legislature to restrict vision to X-rays.
The first medical x-ray in the United States was of a Colles fracture in a boy who had injured his wrist, taken by Edwin Frost, an astronomer from Dartmouth in February 1896, for his doctor brother. That same month, John Cox of McGill University in Canada located a bullet in the leg of a patient who had escaped surgeons. At the end of the year, X-rays entered the battlefield during the Nile Expedition, to help surgeons cope with war wounds. Much of current radiographic practice dates back to 1896, when clinical radiology was born.
Before Roentgen, the disease was inferred by sound, percussion and auscultation. X-rays ensured that the disease was not only heard but seen. The Frankfurter Zeitung called X-rays “a historical result of exact science research”. Rightly so, the first Nobel Prize in Physics, awarded to Roentgen in 1901, was for a medical breakthrough. Roentgen made medicine an applied science by introducing physics into medicine. X-rays later revealed another mystery – the structure of DNA – thanks to X-ray crystallography.
Roentgen dodged fame and turned down fortune. He refused to copyright his discovery. He donated his Nobel Prize to universities. Unpretentious in fame, he was unfazed even before his fame. Known for his honor as a scout, he was once kicked out of school for refusing to denounce his classmate who drew a caricature of a teacher.
When a reporter asked him what he thought when he saw the glow of the distant paper, he replied curtly. “I didn’t think so, I investigated.” Roentgen’s legacy to mankind made the disease more visible to doctors. His legacy to doctors was the double act of observation and investigation.
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Roentgen WC. On a new type of rays. German to English translation of Roentgen’s first radiographic publication by A. Stanton. Science 1896; 3: 227 – 231
Saurabh Jha is a radiologist and contributor to THCB. Jeanne Elkin is MS-3 at the Perelman School of Medicine at the University of Pennsylvania
A modified version of the article was published in Medscape