Lenses from the Finsen lamp
1890-1900
1890-1900
1900-1950
1920-1930
1897
1971
1960
1888
1945-1955
1921
1893
1977
1980-1982
circa 1890
1870-1878
1801-1822
1916
1913-1914
circa 1900-20
1895
1950-1970
1977
1914
1900
1926
1979
2006
2020
1998
1954
1936-1985
c1850
1839
c1870
1967
c1900
1955
1933
1955-1960
1937
1922
circa 1940
1850
1860-1950