Caroline van Loen was the sixth child of Abraham van Loen and Cato Hirsch. From October 1905 she studied mathematics and physics in Leiden. On 1 May 1918 she got a job at the library of the Leiden University. Besides her job at the library, she also was a member of the board of the Jewish Orphanage in Leiden. Carolina van Loen was, together with Elsa Oppenheim, responsible for "monitoring and givi…