
Moving magnet galvanometer with dial inscribed "Greenwich Mean Time", 1843-1897
1843-1897
1843-1897
1831
1930
1900-1950
1857
1868
1940-06-15
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1966-1970
1870-1900
1857
1938-11
1906-1907
1939
1937-02
1939
1925-1935
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920
1900-1920