The End of Medicine’s Blindness – Wilhelm Röntgen and the Discovery of X-rays
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Friday Night, 8 November 1895, in Würzburg: A Dark Laboratory, a Spontaneously Glowing Screen, and an Invisible Ray — Wilhelm Röntgen, X-rays, and Medicine’s First Look Inside the Body
Anesthesia (days 78-79) removed pain; antisepsis (day 80) prevented death. Yet at the end of the 19th century, physicians still worked with a profound blindness: they could not see inside the body. Diagnosis relied entirely on examination by touch from the outside (palpation), listening (auscultation), tapping to produce sounds (percussion), and observation. Where a tumor was located, how large it was, and whether it had spread to bone could be seen only on the operating table, once the body was opened. In a sense, surgeons worked with their eyes closed. On Friday night, 8 November 1895, that blindness suddenly ended. In the dark physics laboratory of the university in Würzburg, Germany, the 50-year-old Professor Wilhelm Conrad Röntgenwas experimenting with cathode-ray tubes (Crookes/Hittorf tubes). Although he had completely covered the tube with an opaque black cardboard sleeve, he noticed a screen across the room, approximately two and a half meters away , coated with barium platinocyanide, glowing greenish of its own accord. There was no visible light; the tube was fully covered, with cardboard, air, and distance in between. Yet the screen glowed. Röntgen was deeply astonished. He spent the next six to seven weeks investigating the properties of this invisible ray with almost no interruption, at times eating and sleeping in the laboratory. He discovered that the ray passed through paper, wood, fabric, and even the soft tissues of the human hand but was stopped by lead and bones. Because he did not know its nature, he named it using the mathematical letter for an unknown: “X-ray” (X-Strahlen) . On 22 December 1895, he placed his wife Anna Bertha Ludwig’s left hand on a photographic plate. After a fifteen-minute exposure, the resulting image became the first medical radiograph in human history: the finger bones, joints, and wedding ring on her ring finger were clearly visible through the flesh. Looking at the image, Anna shuddered and said: “I have seen my own death.” This sentence became the birth cry of modern medical imaging. Today, on day 81 of the series, we examine the discovery of X-rays, their remarkably rapid entry into medical practice, and how they led to the birth of cancer diagnosis and treatment through radiology and radiation oncology.
The man expelled from school because of someone else’s prank
Wilhelm Conrad Röntgen was born on 27 March 1845 in Lennep, in Germany’s Rhine region, now part of Remscheid and home to the Deutsches Röntgen-Museum. His father was a textile merchant. When Wilhelm was three, the family moved to his mother’s hometown, Apeldoorn in the Netherlands. While studying at Utrecht Technical School, the young Röntgen refused to identify the student who had drawn a caricature of a teacher and was consequently expelled from school. This misfortune followed him throughout his life: without an official secondary-school diploma, he could not enter Dutch or German universities through the normal route.
He found a solution in Zurich. Switzerland’s ETH Zurich (Eidgenössische Polytechnische Schule) admitted students through an entrance examination rather than a diploma. Röntgen studied mechanical engineering there and received his doctorate in physics from the University of Zurich in 1869. He became an assistant to his teacher, the renowned physicist August Kundt, and worked with him at the universities of Würzburg and Strasbourg. Interestingly, his lack of a diploma prevented him from receiving an academic appointment in Würzburg for a time, but his talent was undeniable and he was eventually accepted. In 1888, he became Professor of Physics and Director of the Physics Institute at the University of Würzburg . In 1894, he was elected rector of the university.
A note on his character: Röntgen was an exceptionally meticulous, reserved experimentalist who avoided showmanship. He often performed his famous experiments alone, without assistants. On the night of the discovery, he was alone in the laboratory; in his own words, “there were no longer any serving spirits in the house.” He was almost uncomfortable with the enormous fame that followed the discovery. He refused to patent X-rays and said that his discovery should belong to all humanity. This ethical position was the opposite of Morton’s ether patent scandal (day 78). Röntgen donated the prize money of 50.000 Swedish kronor from the first Nobel Prize in Physics, awarded to him in 1901, to the University of Würzburg.
The Crookes tube: the star of physics laboratories in the 1890s
The device Röntgen worked with in 1895 was one of the most prized objects in physics laboratories of the time: the cathode-ray tube (Crookes tube or Hittorf tube). It was an evacuated glass tube. When a high-voltage electric current passed between two electrodes inside, a visible glow traveled from the negative electrode (cathode) toward the positive electrode (anode). This glow was called “cathode rays”; they would later be understood as a flow of electrons (J.J. Thomson, 1897).
By 1895, many European physicists were studying cathode rays, including Philipp Lenard in Germany and William Crookes in England. Röntgen was part of this research effort, trying to measure how far cathode rays could travel outside the tube. An ironic historical detail is that several physicists, particularly Lenard and even Nikola Tesla in the USA, had unknowingly observed the effects of X-rays before the discovery but had passed over them without understanding them. What distinguished Röntgen was that he took the unexpected observation seriously and investigated it systematically.
A dark laboratory and a spontaneously glowing screen
Dark laboratory · The hour of modern medical imaging’s birth
That evening, Röntgen was testing whether cathode rays could escape the tube. To make a sensitive observation, he covered the tube completely with an opaque black cardboard sleeve and made the laboratory pitch-dark. The aim was to see any faint light leaking from the tube in the darkness.
He applied a high voltage to the tube. Out of the corner of his eye, he saw something unexpected: on the workbench, approximately two and a half meters from the tube , a paper screen coated with barium platinocyanide crystals was glowing greenish of its own accord.
This was impossible. The tube was fully covered; no visible light could escape. Cathode rays could not travel that far, since they faded after a few centimeters in air. There were cardboard, air, and distance in between. Röntgen switched off the tube: the glow disappeared. He switched it on: the glow returned. He moved the screen farther away: the glow weakened but persisted. He placed objects—a book, a piece of wood, a metal plate—between the tube and screen: some cast shadows, while others did not.
Röntgen realized that he had discovered an unknown, invisible, penetrating new type of ray . He named it using the mathematical letter for an unknown: “X-Strahlen” — X-rays . He returned home late that night and said nothing to his wife Anna. In the days that followed, he almost shut himself away in the laboratory.
Röntgen spent the next six to seven weeks in one of history’s most intense periods of scientific observation. Working alone and systematically, he established the basic properties of X-rays one by one: they passed through paper, wood, fabric, and thin metal; lead and thick metals stopped them; they darkened photographic plates; they traveled in straight lines; and magnets did not deflect them, distinguishing them from cathode rays—electrons.
The first medical radiograph in human history
Having realized that X-rays could pass through the human body, Röntgen decided to produce the most striking proof. On 22 December 1895 , he called his wife Anna Bertha Ludwig into the laboratory. He placed her left hand on a photographic plate and exposed it to rays from the X-ray tube for approximately fifteen minutes .
When the plate was developed, the resulting image became one of medical history’s most famous pictures: Anna’s hand bones were clearly visible, the soft tissues appeared as faint shadows, and the wedding ringon her ring finger stood as a dark, opaque band over the bones. For the first time, a person had seen their own skeleton while still alive.
(German: “Ich habe meinen Tod gesehen.”)
Anna’s reaction captures the emotional essence of modern imaging’s birth. For someone in the Victorian era, seeing one’s own skeleton was not simply a scientific curiosity, but a direct, unsettling reminder of death and mortality—a memento mori. The skeleton had always symbolized death in art and religion; now a woman was looking at her own skeleton while still alive. This image was reproduced repeatedly in newspapers as news of X-rays spread around the world and captured the public imagination.
The fastest-spreading discovery in the history of science
Röntgen wrote up his observations quickly but meticulously. On 28 December 1895, he submitted his first scientific paper to the Würzburg Physical-Medical Society: “Über eine neue Art von Strahlen” (On a New Kind of Rays). On 1 January 1896, he mailed copies of the paper and several X-ray images to leading physicists in Europe, including Ludwig Zehnder in Freiburg.
What followed was an unprecedented phenomenon of speed in the history of science:
NEWS OF X-RAYS SPREADS WORLDWIDE — WITHIN WEEKS
- 28 December 1895: The first paper was submitted to the Würzburg Physical-Medical Society.
- 1 January 1896: The paper and images were mailed to European physicists.
- 5 January 1896: The Austrian newspaper Wiener Presse announced the news on its front page—the first report to reach the public beyond the scientific community.
- 6-7 January 1896: The news reached London, Paris, and New York by telegraph. The world’s press was filled with headlines about “photographing the invisible.”
- 13 January 1896: Röntgen was summoned to Berlin and demonstrated his discovery before Kaiser Wilhelm II, who immediately awarded him the Prussian Order of the Crown (Second Class) .
- 23 January 1896: Röntgen gave his first public lecture in Würzburg and, in front of the audience, took a live radiograph of the hand of the famous anatomist Albert von Kölliker. Von Kölliker called on the audience to enthusiastically give “three cheers for Röntgen” and proposed calling the new rays “Röntgen rays,” the name still used in the German-speaking world today.
- February 1896: The first clinical X-ray images began to be taken in the USA, England, and France. Fractured bones and embedded bullets or foreign bodies were routinely imaged within weeks.
This speed was unmatched in modern scientific history. The practical value of X-rays was so obvious, and the apparatus so simple—every physics laboratory already had a Crookes tube—that only weeks after the discovery physicians around the world began imaging fractures and foreign bodies. For comparison, full acceptance of Lister’s antisepsis (day 80) took 13 years, while recognition of Long’s ether took 7 years. X-rays became a global practice within weeks.
The first Nobel Prize in Physics in history goes to Röntgen
In 1901, when Nobel Prizes were awarded for the first time, the first Nobel Prize in Physics was awarded to Wilhelm Conrad Röntgen for his “extraordinary services to science through the discovery of X-rays.” Röntgen accepted the award, but avoided publicity to the extent that he refused to give the ceremonial speech in Stockholm. He donated the prize money to the University of Würzburg and never patented his discovery.
A modest ending: The rest of Röntgen’s life was quiet. He became a professor at the University of Munich in 1900. His wife Anna Bertha died in 1919. He lost most of his wealth in Germany’s devastating inflation after World War I and died in relative poverty. On 10 February 1923, he died of intestinal cancer in Munich at the age of 77, ironically from a disease whose diagnosis his discovery would revolutionize. At his request, his personal scientific correspondence was burned after his death, a farewell fitting his modest personality. His name lives on as a unit of measurement—the roentgen, a radiation dose unit—as chemical element 111 (roentgenium, Rg), and in everyday terminology for radiology in the German-speaking world.
Two great gateways to cancer diagnosis and treatment
Röntgen’s discovery opened two separate and enormous gateways in cancer medicine: one to diagnosis, the other to treatment.
X-RAYS × ONCOLOGY — TWO REVOLUTIONS
1. Diagnostic radiology. For the first time, X-rays made it possible to see tumors without opening the body, initially bone tumors and lung masses. This gateway expanded throughout the 20th century: mammographic principles in 1913, computed tomography in the 1970s (BT/CT—Hounsfield, Nobel Prize 1979), followed by magnetic resonance imaging (MR), PET, and hybrid PET/CT imaging. Today, staging a cancer patient—mapping the extent of disease—relies entirely on imaging. The first link in this chain is the night of 8 November 1895 in Würzburg.
2. Radiation oncology (radiotherapy). Soon after it was discovered that X-rays penetrated tissue, it also became clear that they damaged biological tissue . From 1896, less than a year after the discovery, physicians began trying X-rays to treat skin tumors and other cancers. This was the birth of radiation oncology: the principle that ionizing radiation kills cancer cells by damaging their DNA. Today’s radiotherapy—modern linear accelerators, intensity-modulated radiotherapy (IMRT), stereotactic radiosurgery (SRS), and proton therapy—consists of refined descendants of this principle.
THE DARK SIDE — THE PRICE OF RADIATION
The discovery of X-rays had a tragic cost. In the early years, radiation hazards were unknown; inventors, technicians, and physicians worked without protection. Clarence Dally —Thomas Edison’s X-ray assistant—tested the beam with his hands for years. Severe radiation burns were followed by amputation of his arms and death from metastatic cancer in 1904, one of the first known occupational deaths involving X-rays. Many early radiologists developed radiation dermatitis on their hands, followed by skin cancer; many died young. At St. Georg Hospital in Hamburg, a memorial to these “martyrs of radiology” was erected in 1936, bearing 159 names; more were added in later years.
This tragic learning process laid the foundations of modern radiation safety: radiobiology, dose limits, protective equipment, and the ALARA principle—“as low a dose as reasonably achievable.” The same ray was a diagnostic tool, a treatment weapon, and, when used without control, a causeof cancer. This threefold nature remains the delicate balance at the heart of radiation oncology today.
From X-rays to radioactivity: the next link
Röntgen’s discovery in 1895 directly triggered another major discovery. In Paris, the physicist Henri Becquerelwas investigating whether X-rays came from phosphorescent substances when, in 1896, he discovered that uranium salts emitted rays spontaneously —without any external stimulus: radioactivity. A young Polish-French scientist who pursued Becquerel’s work further, Marie Skłodowska Curie, together with her husband Pierre Curie, discovered two new radioactive elements in 1898: polonium (named after Marie’s homeland, Poland) and radium.
Radium soon became the first true radioactive weapon against cancer through “Curie therapy,” or brachytherapy, in which a radioactive source is placed directly in the tumor. Marie Curie became the first person—and for a long time the only one—to win Nobel Prizes in both Physics (1903, with Becquerel and Pierre Curie) and Chemistry (1911). In World War I, she developed mobile X-ray vehicles called “petites Curies” to image wounded soldiers at the front and drove them there herself. Yet Marie Curie also paid the price of radiation: after years of unprotected work with radioactive materials, she died in 1934 of aplastic anemia, most likely due to radiation-related bone marrow failure. Her story will be explored in detail later in the series.
The arrival of X-rays in Ottoman medicine
News of X-rays reached Ottoman Istanbul as quickly as it reached the rest of the world. During 1896 —only months after the discovery—the first X-ray experiments were performed in the physics department of Mekteb-i Tıbbiye-i Şahane, the Imperial Medical School. The speed of Ottoman medicine’s modernization is evident here: each new technology entering routine European practice reached Istanbul increasingly quickly—one and a half years for ether, months for chloroform, and months for X-rays.
The first documented radiological applications in the Ottoman Empire began with X-ray devices used in military surgery during the Ottoman-Greek War of 1897 and later the Balkan Wars (1912-1913), to locate bullets and shrapnel in wounded soldiers. In the Republican era, modern Turkish radiology was established at medical faculties in Istanbul and Ankara; radiation oncology developed in the middle of the 20th century, first with radium tubes and then with linear accelerators. Today, every cancer patient’s diagnostic and staging journey in Turkish oncology—PET/CT, MR, CT—is a direct legacy of the night of 8 November 1895 in Würzburg.
THE ROOTS OF CANCER DIAGNOSIS AND RADIOTHERAPY
INFORMATION VERIFIED IN THIS ARTICLE
- Wilhelm Conrad Röntgen: 27 March 1845, Lennep (now Remscheid), Germany — 10 February 1923, Munich (intestinal cancer). Grew up in Apeldoorn in the Netherlands; expelled from Utrecht Technical School for someone else’s offense; ETH Zurich, doctorate in physics from the University of Zurich in 1869.
- Academic career: Assistant to August Kundt; Professor of Physics and Institute Director at the University of Würzburg in 1888; rector in 1894; University of Munich in 1900.
- Date of discovery: Friday evening, 8 November 1895, Würzburg. Crookes/Hittorf cathode-ray tube, opaque black cardboard sleeve, glowing barium platinocyanide screen approximately 2.7 m (9 feet) away.
- Naming: “X-Strahlen” (X-rays); X = the mathematical unknown. Von Kölliker proposed “Röntgen rays,” still used in the German-speaking world.
- First medical radiograph: 22 December 1895, his wife Anna Bertha Ludwig’s left hand + wedding ring, approximately 15 minutes of exposure. “I have seen my own death” (“Ich habe meinen Tod gesehen”).
- First paper: 28 December 1895, “Über eine neue Art von Strahlen,” Würzburg Physical-Medical Society.
- Dissemination: Mailed to physicists on 1 January 1896 (Ludwig Zehnder, Freiburg); Wiener Presse on 5 January; Kaiser Wilhelm II + Prussian Order of the Crown on 13 January; public lecture in Würzburg + demonstration of von Kölliker’s hand on 23 January 1896.
- Nobel Prize: 1901, history’s first Nobel Prize in Physics. He donated the prize money to the University of Würzburg and did not patent the discovery.
- The Becquerel-Curie chain: 1896: Becquerel, radioactivity; 1898: Marie and Pierre Curie, polonium + radium.
- Clarence Dally: Edison’s X-ray assistant, died of metastatic cancer in 1904; one of the first known occupational cancer deaths involving X-rays.
- Hamburg memorial to the martyrs of radiology: 1936, St. Georg Hospital, initially 159 names.
- Lasting legacy: The roentgen (radiation dose unit), roentgenium (element 111, Rg), and everyday German radiology terminology.
Marie Curie, Radioactivity, and the Dark Glow of Radium: Paris 1898, Two Nobel Prizes, and the First Radioactive Weapon Against Cancer
Röntgen’s discovery of X-rays (day 81) triggered Henri Becquerel’s discovery of radioactivity in Paris, and a young Polish scientist, Marie Skłodowska Curie, explored this phenomenon in depth. Together with her husband Pierre, she processed tons of pitchblende ore in a shed and isolated two new elements in 1898: polonium and radium. Radium became the first radioactive weapon for treating cancer through brachytherapy/Curie therapy. Marie Curie was the first person to win Nobel Prizes in two separate sciences—Physics in 1903 and Chemistry in 1911. She served at the front with mobile X-ray vehicles during World War I and ultimately became a victim of years of unprotected radiation exposure, dying of aplastic anemia in 1934. Her notebooks remain so radioactive today that they are kept in lead boxes and require protective clothing to read. Tomorrow, we will examine this extraordinary story.
Author’s note: Anna Bertha Ludwig’s statement, “I have seen my own death,” is an anecdote widely reported in medical history sources. The exact German wording and context vary slightly between sources, but the essence is consistent. Some sources state that Röntgen’s first image was actually a lost radiograph of his own hand, while Anna’s hand was the first documented and preserved medical radiograph. Lenard’s and Tesla’s earlier observations are discussed historically as scientific phenomena that preceded the discovery but were not understood. Priority belongs unquestionably to Röntgen because he performed the systematic investigation and publication. Day 82 will cover Marie Curie and radium, while later days will examine the development of radiation oncology, Hounsfield’s computed tomography, and modern imaging in detail.
Sources and Further Reading
- Röntgen WC. Über eine neue Art von Strahlen. Sitzungsberichte der Würzburger Physikalisch-Medizinischen Gesellschaft, 28 December 1895. (The original paper announcing the discovery of X-rays.)
- Glasser O. Wilhelm Conrad Röntgen and the Early History of the Roentgen Rays. Springfield, IL: Charles C. Thomas, 1934. (The classic scientific biography of Röntgen.)
- Nobel Foundation. The Nobel Prize in Physics 1901 — Wilhelm Conrad Röntgen. nobelprize.org. (Official record of the first Nobel Prize in Physics.)
- Linda Hall Library. Wilhelm Röntgen — Scientist of the Day. 2024. (Academic biographical summary; details of von Kölliker’s radiograph.)
- American Physical Society. November 8, 1895: Roentgen's Discovery of X-Rays. APS News, 2001. (Technical details of the night of discovery.)
- Deutsches Röntgen-Museum. Remscheid-Lennep, Germany — Röntgen biography and archive of the first radiographs.
- Deutsches Patent- und Markenamt (DPMA). Röntgen's X-rays — Inventions That Made History. (Technical and historical assessment of the discovery.)
- Mould RF. A Century of X-rays and Radioactivity in Medicine. Bristol: Institute of Physics Publishing, 1993. (A century of X-rays and radioactivity in medical history.)
- Kevles BH. Naked to the Bone: Medical Imaging in the Twentieth Century. New Brunswick: Rutgers University Press, 1997. (The social and scientific history of medical imaging.)
- Brown P. American Martyrs to Science Through the Roentgen Rays. Springfield, IL: Charles C. Thomas, 1936. (History of the early martyrs of radiology, including Clarence Dally and others.)
- Mukherjee S. The Emperor of All Maladies: A Biography of Cancer. New York: Scribner, 2010. (The chapter on the birth of radiation oncology.)
- Turkish Society of Radiology & Turkish Society for Radiation Oncology. A review of the history of radiology and radiation oncology in Türkiye. (The development of X-rays and radiotherapy from the Ottoman era to the Republic.)
This article is day 81 of the History of Cancer in 365 Days Series. Wilhelm Conrad Röntgen’s discovery of X-rays on 8 November 1895 is the birth certificate of modern medical imaging and, indirectly, radiation oncology. After anesthesia (days 78-79) and antisepsis (day 80) made modern surgery possible, X-rays added the ability to “see inside the body,” launching the diagnostic revolution. The same discovery established the foundations of cancer diagnosis through radiology, cancer treatment through radiotherapy, and, tragically, the possibility that radiation itself could be a cause of cancer. This threefold nature lies at the ethical and technical center of radiation science. In today’s oncology practice, every patient’s diagnostic, staging, and follow-up journey relies on imaging, and the first link in this chain is the night of 8 November 1895 in Würzburg. This article takes a popular historical perspective and does not provide medical treatment advice. Radiation’s tragic early cost—Clarence Dally, the martyrs of radiology, and Marie Curie—laid the foundations of modern radiation safety. This subject is presented for informational purposes for readers with concerns about radiation. All dates, biographical details, and locations in the article were verified using Röntgen’s original 1895 paper, Glasser’s classic 1934 biography, official Nobel Foundation records, biographical accounts from the Linda Hall Library and American Physical Society, the Deutsches Röntgen-Museum archive, and modern medical history sources.
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