
Cooke and Wheatstone's ABC telegraph transmitter
1840
1840
1839
1856
1843
1845-1855
1829
circa 1852
1854
1840-1848
circa 1852
1842
1852
1847
1842
1913; circa 900 CE
1855
1855
1856
1798 (original); 1977 (model)
1840
1845
1834
1834
1834
1845-1850
1832-1840
1851-1856
1835-1845
after 1851
1840-1850
1830
1847
1843
1846-1852
1853
1855
1852
1830
1850
1850
1838-1849
1849
1840
1836-1856
1843
1848
1830-1839
1852
1846
1828-1838