
Cooke and Wheatstone's four needle telegraph, 1838
1838
1838
1909-1910
1936
1949
circa 1900
1800-1872
1970
1983
1752
1762
1762
1900-1909
1837
1781-1790
2014
1775
1650-1665
1752
1923
1720
1835
1853-1857
1761-1762
1930-1960
1770-1780
circa 1932
1978
1780-1790
1872
1968-1972
1900-1914
1871-1900
1980-1983
1867
1920-1925
1850-1925
1850-1904
1936-1938
1850-1905
1850-1899
1750
1890-1913
1925-1931
circa 1933-circa 1971
1900-1950
1940-1947
1916-1940
1920-1960