
Strowger step-by-step automatic telephone exchange switch, 1897-1898
1897-1898
1897-1898
1801-1840 (original); 1901 (model)
1839 (original); circa 1988 (replica)
1897
1898
1955; 1830
1897
1898
1872 (original); 1909 (model)
1898
circa 1897
2000-100 BCE
1898
1934
1898
1897
1897
1897
1897
1772 (original); 1919 (model)
1990-96
1830 (original); 1967 (model)
1775-1799 (original); 1900-1907 (model)
1897
4000-2001 BCE
1897
1897
1897
1930 (replica); 1834 (original)
1897
1925; 1862
1705-1737
1801-1892 (prepared); 1946 (element replaced)
1898
1934
1898
1898
1990-95
1897
1668; 1924
1897
1897
1976; 1776
1834-1836
1610; 1923
1897
1929 (copy); 1702-1714 (original)
300 BCE; 1905-1915
1897
1897