Roentgen demonstrating his discovery

Wilhelm Conrad Roentgen (1845-1923) demonstrated his newly discovered x-rays by photographing bones in a hand at the University of Wurzburg, Germany in January 1896.

Courtesy of Parke Davis
January 1896
Wurzburg, GERMANY
© CHIN 2001


X-rays were accidentally discovered by the physicist Wilhelm Roentgen while he was studying the cathode rays produced by an electrical current passed through a glass tube. Despite the fact that the tube was encased in a black cardboard box, Roentgen noticed that a barium-platinocyanide screen, inadvertently lying nearby, emitted fluorescent light whenever the tube was in operation. With further experiments, he determined that the fluorescence was caused by invisible radiation of a more penetrating nature than ultraviolet rays. He named the invisible radiation "x-rays" because of its unknown nature.

In January of 1896, Roentgen presented his findings to the Wurzburg-Medical Society. He demonstrated his discovery with an x-ray of the hand of a famous anatomist, von Kolliker.

Roentgen was the recipient of the first Nobel Prize for Physics in 1901 for this discovery.
X-rays were accidentally discovered by the physicist Wilhelm Roentgen while he was studying the cathode rays produced by an electrical current passed through a glass tube. Despite the fact that the tube was encased in a black cardboard box, Roentgen noticed that a barium-platinocyanide screen, inadvertently lying nearby, emitted fluorescent light whenever the tube was in operation. With further experiments, he determined that the fluorescence was caused by invisible radiation of a more penetrating nature than ultraviolet rays. He named the invisible radiation "x-rays" because of its unknown nature.

In January of 1896, Roentgen presented his findings to the Wurzburg-Medical Society. He demonstrated his discovery with an x-ray of the hand of a famous anatomist, von Kolliker.

Roentgen was the recipient of the first Nobel Prize for Physics in 1901 for this discovery.
Canadian Heritage Information Network
© CHIN 2001

X-rays are a form of electromagnetic radiation created when high-speed electrons bombard and interact with the atoms in a metal target. The two essential parts of an x-ray machine are an x-ray tube and a source of high voltage electricity (the induction coil). These were common pieces of apparatus in the physics laboratories of the late 19th century.

The first x-ray tube was the Crookes tube, a partially evacuated glass bulb containing two electrodes, designed by British experimenter William Crookes. When an electric current passes through the tube, a beam of electrons is emitted from the cathode, and travels toward the anode. Experimenters in the 19th century called this a ""cathode ray."" The interaction of these rays with the gas molecules in the tube and the glass walls of the tube caused a fluorescence. These were the phenomena that Roentgen was studying. X-rays were a side-effect, produced when the high-speed electrons were suddenly stopped as they hit the anode. Crookes tubes produced "soft" x-rays of low energy.

An x-ray machine is much like a camera. X-rays cause chemical changes that darken photographic plates. Since x Read More
X-rays are a form of electromagnetic radiation created when high-speed electrons bombard and interact with the atoms in a metal target. The two essential parts of an x-ray machine are an x-ray tube and a source of high voltage electricity (the induction coil). These were common pieces of apparatus in the physics laboratories of the late 19th century.

The first x-ray tube was the Crookes tube, a partially evacuated glass bulb containing two electrodes, designed by British experimenter William Crookes. When an electric current passes through the tube, a beam of electrons is emitted from the cathode, and travels toward the anode. Experimenters in the 19th century called this a ""cathode ray."" The interaction of these rays with the gas molecules in the tube and the glass walls of the tube caused a fluorescence. These were the phenomena that Roentgen was studying. X-rays were a side-effect, produced when the high-speed electrons were suddenly stopped as they hit the anode. Crookes tubes produced "soft" x-rays of low energy.

An x-ray machine is much like a camera. X-rays cause chemical changes that darken photographic plates. Since x-rays pass through some tissues and bone more easily than others, when a body part is placed between the source of x-rays and the photographic plate, an image of the interior structure is produced. For example, the lungs contain mostly air and do not absorb x-rays. Hence they appear black on the x-ray pictures. On the other hand, bones absorb x-rays and appear white.

© CHIN 2001

Crookes Tube

The first x-ray tube was the Crookes tube.

Manufacturer unknown
Museum of Health Care at Kingston
Date unknown
994010011
© CHIN 2001


Throughout the 19th century, physicians had searched for ways to visualize the interior of the living body. The discovery of x-rays revolutionized diagnosis in medicine. At last there was a means to obtain images of disease processes in the living.

X-ray imaging was rapidly introduced in many centers of medicine. Within two months of the announcement of Roentgen's discovery, x-ray images were made by the physicist John Cochrane in his laboratory at the Royal Military College in Kingston. He gave public demonstrations and local doctors asked to use his x-ray apparatus for diagnostic purposes.

In the fall of 1896, Kingston General Hospital was one of the first hospitals in Canada to acquire an x-ray machine. It consisted of an induction coil capable of generating 100 000 volts, and an x-ray tube.

The new x-ray machine was tested with volunteers. The value of the machine was demonstrated by an x-ray of a volunteer's hand.

James Third, the hospital radiographer, was an advocate of the use of x-rays in the early diagnosis of tuberculosis in the lung and joints.
Throughout the 19th century, physicians had searched for ways to visualize the interior of the living body. The discovery of x-rays revolutionized diagnosis in medicine. At last there was a means to obtain images of disease processes in the living.

X-ray imaging was rapidly introduced in many centers of medicine. Within two months of the announcement of Roentgen's discovery, x-ray images were made by the physicist John Cochrane in his laboratory at the Royal Military College in Kingston. He gave public demonstrations and local doctors asked to use his x-ray apparatus for diagnostic purposes.

In the fall of 1896, Kingston General Hospital was one of the first hospitals in Canada to acquire an x-ray machine. It consisted of an induction coil capable of generating 100 000 volts, and an x-ray tube.

The new x-ray machine was tested with volunteers. The value of the machine was demonstrated by an x-ray of a volunteer's hand.

James Third, the hospital radiographer, was an advocate of the use of x-rays in the early diagnosis of tuberculosis in the lung and joints.

© CHIN 2001

John Cochrane

John Bray Cochrane (1860-1946), professor of physics and chemistry at the Royal Military College of Canada, was the first person in Kingston, Ontario, to build and use an x-ray apparatus.

Photo courtesy of Massey Library, Royal Military College of Canada.
1860 - 1946
Photograph
© CHIN 2001


Reproduction of original x-ray equipment

A reconstruction of the x-ray apparatus purchased for use at the Kingston General Hospital in the fall of 1896.

Bernard Ziomkiewicz
Museum of Health Care at Kingston - on loan from the Department of Physics, Queen´s University
c. 1996
Original X-ray Equipment (reproduction)
© CHIN 2001


X-ray of hand

X-ray of a hand of a volunteer to test the new x-ray machine at the Kingston General Hospital.

Kingston General Hospital
Museum of Health Care at Kingston
c. 1896
Kingston, Ontario, CANADA
X-ray
997029001
© CHIN 2001


X-ray of tubercular elbow joint

Radiograph of tuberculosis of the elbow, taken by Dr. James Third. Despite the poor quality of the image, rarefaction of the bones and soft-tissue swelling can be seen.

Kingston General Hospital
Queen´s University Archives
Date unknown
Kingston, Ontario, CANADA
X-ray
© CHIN 2001


Learning Objectives

The learner will:

  • Identify and appreciate the way history and culture shape a society’s science and technology
  • Provide examples of how science and technology have influenced the diagnosis and treatment of human illness, and have made medical technology an integral part of our lives
  • Describe scientific and technological developments, past and present, and appreciate their impact on individuals and societies
  • Describe how Canadians have contributed to science and technology on the global stage

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