
Lord Kelvin's magnetic deflector
1901
1901
1903
1904
1904
1903
1900-1915
1903
1903
1907-1912
1912
1900
1903
1903
1903
1903
1903
1903
1903
1913
1903
1900
1920
1910-1925
1908
1904
1902
1908
1907
1910
1915-1925
1901-1910
1906
1913
1925
1906-1908
1908-1900
1910-1920
1915
1902
1902
1925
1917
1927
1917
1907
1908
1909
circa 1900
2000-1350
1914-1918