Rasmus Bartholin
Rasmus Bartholin was a Danish
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

 scientist and physician. As part of his studies, he travelled in Europe for ten years. Professor at the University of Copenhagen
University of Copenhagen
The University of Copenhagen is the oldest and largest university and research institution in Denmark. Founded in 1479, it has more than 37,000 students, the majority of whom are female , and more than 7,000 employees. The university has several campuses located in and around Copenhagen, with the...

, first in Geometry, later in Medicine. He was a younger brother of Thomas Bartholin.

Rasmus Bartholin is remembered especially for his discovery (1669) of the double refraction
Birefringence, or double refraction, is the decomposition of a ray of light into two rays when it passes through certain anisotropic materials, such as crystals of calcite or boron nitride. The effect was first described by the Danish scientist Rasmus Bartholin in 1669, who saw it in calcite...

 of a light ray by Iceland spar
Iceland spar
Iceland spar, formerly known as Iceland crystal, is a transparent variety of calcite, or crystallized calcium carbonate, originally brought from Iceland, and used in demonstrating the polarization of light . It occurs in large readily cleavable crystals, easily divisible into rhombs, and is...

Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

). He published an accurate description of the phenomenon, but since the physical nature of light was poorly understood at the time, he was unable to explain it. It was only after Thomas Young
Thomas Young (scientist)
Thomas Young was an English polymath. He is famous for having partly deciphered Egyptian hieroglyphics before Jean-François Champollion eventually expanded on his work...

 proposed the wave theory of light, c. 1801 that an explanation became possible.

Important Facts

1. Dates

Born: Roskilde, Denmark, 13 Aug. 1625

Died: Copenhagen, 4 Nov. 1698

Dateinfo: Dates Certain

Lifespan: 73

2. Father

Caspar Bartholin
Caspar Bartholin the Elder
Caspar Bartholin the Elder was born at Malmø, Denmark and was a polymath, finally accepting a professorship in medicine at the University of Copenhagen, Denmark, in 1613...

Occupation: Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...

, Academic

He died when Erasmus was four. No clear information on financial status.

3. Nationality

Birth: Roskilde, Denmark

Career: Denmark

Death: Copenhagen, Denmark

4. Education

Taught initially by private teachers, then attended Latin school.

Univ. of Copenhagen (1642-4), B.A. in 1644. M.A. in 1647.

Studied mathematics at the University of Leiden for several years beginning in 1645.

1651: studied mathematics in France and Italy, ultimately at the Padua
University of Padua
The University of Padua is a premier Italian university located in the city of Padua, Italy. The University of Padua was founded in 1222 as a school of law and was one of the most prominent universities in early modern Europe. It is among the earliest universities of the world and the second...

 where he was Consiliarius for the German Nation and Vice-syndicus for the university.

M.D., 1654 at Padua.

1654-6: travelled and studied in Italy.

5. Religion

Affiliation: Lutheran.

6. Scientific Disciplines

Primary: Mathematics, Optics

Subordinate: Medicine, Astronomy

Major contribution to science was his study of Icelandic spar.

Writings in pure mathematics were fairly numerous but not of great importance.

Wrote a little on medicine.

Observed the comets of 1665 and other astronomical objects, and published about this topic.

7. Means of Support

Primary: Academia, Patronage, Government

Professor of mathematics at Copenhagen, 1657.

Extraordinary chair of medicine, 1657.

Royal Mathematician, 1667.

Ordinary chair of medicine, 1671.

Teacher to Prince Joergen, 1671.

Dean of the faculty of medicine.


Rector in three different years.

Royal physician.

Privy concilor, Advisor to the chancellor, then minister of justice.

8. Patronage

Type: Court Official

He was supported and directed by Frederick III of Denmark
Frederick III of Denmark
Frederick III was king of Denmark and Norway from 1648 until his death. He instituted absolute monarchy in Denmark and Norway in 1660, confirmed by law in 1665 as the first in western historiography. He was born the second-eldest son of Christian IV of Denmark and Anne Catherine of Brandenburg...

 to prepare for publication the collected manuscript observations of Tycho Brahe
Tycho Brahe
Tycho Brahe , born Tyge Ottesen Brahe, was a Danish nobleman known for his accurate and comprehensive astronomical and planetary observations...


In addition, all of the connections to the court, and the various appointments above.

9. Technological Involvement

Type: Medical Practice

As a physician, he introduced quinine
Quinine is a natural white crystalline alkaloid having antipyretic , antimalarial, analgesic , anti-inflammatory properties and a bitter taste. It is a stereoisomer of quinidine which, unlike quinine, is an anti-arrhythmic...

 in the fight against malaria
Malaria is a mosquito-borne infectious disease of humans and other animals caused by eukaryotic protists of the genus Plasmodium. The disease results from the multiplication of Plasmodium parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases...


10. Scientific Societies

Memberships: None

He worked with Ole Roemer on Tycho's manuscripts.

He worked with Niels Stensen on crystallography
Crystallography is the experimental science of the arrangement of atoms in solids. The word "crystallography" derives from the Greek words crystallon = cold drop / frozen drop, with its meaning extending to all solids with some degree of transparency, and grapho = write.Before the development of...


External links

  • http://www.experiencefestival.com/erasmus_bartholinus/articleindex
  • http://www.britannica.com/EBchecked/topic/54330/Erasmus-Bartholin
  • http://www.worldcat.org/identities/lccn-n93-3891
  • http://www-history.mcs.st-and.ac.uk/Biographies/Bartholin.html
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