Wilhelm Conrad Roentgen
1845-1923
His X-rays changed
medicine & technology
Structure
 Biography
 X-rays
 Domains
 Historical events
Biography
 Youth
 Study
 Work area
Youth
 27th March 1845:
Wilhelm Conrad Roentgen was born in Lennep (Remscheid)
 1861-1863:
He visited the technical school in Utrecht;
He left without school leaving examination
Study
 1865-1868:
Entrance exam instead of school leaving examination;
Study of mechanical engineering in Zurich
 1868:
Diploma as a mechanical engineer;
After that: study of physics
Work area
 1870:
Move to Wuerzburg; Publication of „Annalen of Physics and Chemistry“
 8th November 1895:
Roentgen discovered the X-rays
 22nd November 1895:
First X-ray pictures
 28th December 1895:
Manuscript „A new kind of rays“ ("Eine neue Art von Strahlen");
Roentgen pointed to the medicine use at the publication;
The deadly side effects of the X-rays were unknown for a long time
 1st April 1900:
Roentgen got the professorship at University Munich
 10th December 1901:
Awarding of the Nobel Prize of Physics
 1st April 1920:
Roentgen was retired in Munich
 10th February 1923:
Wilhelm Conrad Roentgen died in Munich
The X-RAYS
 Pure research
 The „X-rays“
 Applications & property
Pure research
At the end of the 19th century many physicist worked on the “Cathode
ray tube“ that is built like this:
1. Closed glass flask
2. Tension source (a battery wouldn't produce enough tension, so a
spark inductor was used)
3. Anode
4. Cathode
5. Bright ray
The air is pumped out as much as possible of a closed glass flask with
the help of a vacuum pump. The tension source conducts the tension
in the discharge tube: the positive charge to the anode and the negative
one to the cathode. A tension between the anode and the cathode
originates, so you can see a bright ray.
The „X-rays“
On 8th November 1895 Roentgen carried out the experiment with a
charge. He covered the discharge tube completely with black paper,
and light couldn't get out of the tube. Next to the building he put up a
screen with a special mass that lighted up when it was illuminated.
The screen lighted up, although light couldn't get out of the discharge
tube through the black paper. Because of different reasons the rays
couldn't be cathode rays. He took the screen and carried it to the tube.
After that the light became stronger and the bones of his fingers
appeared on the screen. So the rays came through the human body.
Roentgen called them X-rays.
Applications & Property
Application
Property
• in medicine
• invisible for human eyes
• in metallurgy
• ionisers air, gas and
• in technology
light molecules
• in chemical Fundamental • carcinogenic
research (very important) • short wave light
Domains
Universities
Zurich
Strasbourg
Hohenheim
Giessen
Wuerzburg
Munich
Roentgen's work
Doctorate of physics at
University Zurich
Habilitation at
University Strasbourg
Professorship in Physics
and
Mathematic at
agricultural
Academy Hohenheim
Vocation to Giessen as
professor
Vocation for an
ordination in
Wuerzburg; Election as
a
vice-chancellor at
University Wuerzburg
Roentgen got the
professorship
at University Munich
Historical events during his lifetime
 1870's
 1880's
 1890's
 1900's
 1910's
1870's
 1870–1872:
German-French War
 18th January 1871:
Foundation of the German Reich
 1873:
Three-Emperor-Agreement (Germany, Austria, Russia) in Berlin was signed
 1878:
Otto von Bismarck's law against social democracy
 1879:
Alliance between Germany and Austria
1880's
 1882:
Italy became part of the alliance between Germany and Austria (till 1914/15)
 1881-1889:
Installation of Bismarck's social laws in
Germany: Health insurance, accident insurance and pension insurance scheme
1890's
 25th January 1890:
The German sovereign assembly declined the bill of the government about the prolongation of
the socialist law for an indefinite period
 1st April 1892:
Installation of the Central European Time as standardized time for the entire Germany
 5th December 1894:
Emperor Wilhelm II. opened the German sovereign assembly building in Berlin
1900's
 8th April 1904:
Entente Cordinale (Alliance between Great Britain and France to solve a conflict of interests)
1910's
 14th December 1911:
First person reached the South Pole
 1912:
Maiden voyage and sinking of the Titanic
 1914-1918:
First World War
 1918:
November Revolution in Germany
 1919:
Foundation of the Weimarer Republic