Simplify the following text for a Grade 6 native English-speaking person.
Original: Niels Ryberg Finsen ( December 15 , 1860 -- September 24 , 1904 ) was a Faroese physician and scientist of Icelandic descent .
Simplified: Niels Ryberg Finsen ( December 15 , 1860 - September 24 , 1904 ) was an Danish doctor .