Ring transformer, 1892
1892
1892
1901-1913
2000-2002
circa 1950s
1997
1880-1895
1880-1895
1895
1880-1895
1880-1895
1880-1895
1893
1880-1895
1893-1895
1893-1895
1955-1960
1982
1843-1889
1880-1895
1880-1895
1807
1842
circa 1855
1978
1886
before 1889
1939-1945
1893
1850-1900
1850-1900
1850-1900
1880-1895
1893-1895
1893-1895
1880-1895
1880-1895
1893-1895
1880-1895
1880-1895
1880-1895
1880-1895
1880-1895
2015-2018
2016-2017
1982
1993
2016-2017
2020
before 1889
1909-1910