Rasmus Bartholin (; Latinized: ''Erasmus Bartholinus''; 13 August 1625 – 4 November 1698) was a Danish physician and grammarian.

Biography

Bartholin was born in

Roskilde Roskilde ( , ) is a city west of Copenhagen on the Danish island of Zealand. With a population of 51,916 (), the city is a business and educational centre for the region and the 10th largest city in Denmark. It is governed by the administrative ...

. He was the son of

Caspar Bartholin the Elder Caspar Bartholin the Elder (; 12 February 1585 – 13 July 1629) was a Danish physician, scientist and theologian. Biography Caspar Berthelsen Bartholin was born at Malmö, Malmø, Denmark (modern Sweden). His precocity was extraordinary; at thr ...

(1585–1629) and Anna Fincke, daughter of the mathematician Thomas Fincke. As part of his studies, he travelled in Europe for ten years. He stayed in the Netherlands, England, France and Italy. In 1647, he took a

Master's degree A master's degree (from Latin ) is an academic degree awarded by universities or colleges upon completion of a course of study demonstrating mastery or a high-order overview of a specific field of study or area of professional practice.

at the

University of Copenhagen The University of Copenhagen ( da, Københavns Universitet, KU) is a prestigious public university, public research university in Copenhagen, Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in ...

. In 1654, he received a Doctoral degree at the

University of Padua The University of Padua ( it, Università degli Studi di Padova, UNIPD) is an Italian university located in the city of Padua, region of Veneto, northern Italy. The University of Padua was founded in 1222 by a group of students and teachers from ...

. He was a professor at the

, first in

Geometry Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...

, later in Medicine. He was also dean of the faculty of medicine, librarian, and rector. He wrote, in Latin, the first grammar of the

Danish language Danish (; , ) is a North Germanic language spoken by about six million people, principally in and around Denmark. Communities of Danish speakers are also found in Greenland, the Faroe Islands, and the northern German region of Southern Schl ...

, the 1657 ''De studio lingvæ danicæ''. Rasmus Bartholin is remembered especially for his discovery (1669) of the double refraction of a light ray by

Iceland spar Iceland spar, formerly called Iceland crystal ( is, silfurberg , ) and also called optical calcite, is a transparent variety of calcite, or crystallized calcium carbonate, originally brought from Iceland, and used in demonstrating the polarizati ...

(

calcite Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scratc ...

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

Personal

He was a younger brother of

Thomas Bartholin Thomas Bartholin (; Latinized as ''Thomas Bartholinus''; 20 October 1616 – 4 December 1680) was a Danish physician, mathematician, and theologian. He is best known for his work in the discovery of the lymphatic system in humans and for hi ...

(1616–1680).

References

External links

* "De figura nivis". In Thomas Bartolin, . Copenhagen: P. Haubold, 1661 *
Bartholin, Erasmus 1625-1698
worldcat.org {{DEFAULTSORT:Bartholin, Rasmus 1625 births 1698 deaths 17th-century Danish physicians 17th-century Danish scientists University of Copenhagen alumni University of Padua alumni University of Copenhagen faculty Medical educators Mathematics educators People from Roskilde Rectors of the University of Copenhagen Bartholin family