Rasmus Bartholin

Rasmus Bartholin studied at University of Copenhagen and University of Padua. The recorded working language is Latin, Danish and German. The field of work recorded is physics, astronomy and medicine. Residence is recorded at Denmark. Employment is recorded with University of Copenhagen. Positions recorded include rector.

• Name — Rasmus Bartholin • Born — 13 August 1625 • Birthplace — Roskilde • Died — 4 November 1698 (aged 73) • Place of death — Copenhagen • Field — Physics • Known for — Double refraction of a light ray

Bartholin was born in Roskilde. 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 at the University of Copenhagen. In 1654, he received a Doctoral degree at the University of Padua. He was a professor at the University of Copenhagen, first in Geometry, 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, 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 (calcite). 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.

He was a younger brother of Thomas Bartholin (1616–1680).

His recorded languages were Latin, Danish and German. He was the child of Caspar Bartholin the Elder and Anna Cathrine Thomasdatter Bartholin. One child is recorded: Anne Marie Bartholin. Other recorded relations include Thomas Fincke and Ole Rømer.