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 53,354 (), 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 (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 a postgraduate 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 prac ...

at the

University of Copenhagen The University of Copenhagen (, KU) is a public university, public research university in Copenhagen, Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in Scandinavia, after Uppsala University. ...

. In 1654, he received a Doctoral degree at the

University of Padua The University of Padua (, UNIPD) is an Italian public research university in Padua, Italy. It was founded in 1222 by a group of students and teachers from the University of Bologna, who previously settled in Vicenza; thus, it is the second-oldest ...

. He was a professor at the

, first in

Geometry Geometry (; ) is a branch of mathematics concerned with properties of space such as the distance, shape, size, and relative position of figures. Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician w ...

, 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 languages, North Germanic language from the Indo-European languages, Indo-European language family spoken by about six million people, principally in and around Denmark. Communities of Danish speakers are a ...

, 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 ( , ) and also called optical calcite, is a transparent variety of calcite, or crystallized calcium carbonate, originally brought from Iceland, and used in demonstrating the polarization of light. For ...

(

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

). 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 may refer to: People * List of people with given name Thomas * Thomas (name) * Thomas (surname) * Saint Thomas (disambiguation) * Thomas Aquinas (1225–1274) Italian Dominican friar, philosopher, and Doctor of the Church * Thomas the A ...

(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 Academic staff of the University of Copenhagen Medical educators Danish mathematics educators People from Roskilde Rectors of the University of Copenhagen Bartholin family