
Theodolite used for the Principal Triangulation of Great Britain
1791
1791
1668; 1924
1610; 1923
1642-1649 (original); 1883 (model)
1791
1792
1792
1792
2000-100 BCE
1772 (original); 1919 (model)
1792
1791-1792
1990-96
1705-1737
1791
4000-2001 BCE
1990-95
1730-1760 (original); 1931-1939 (replica)
2800 BCE
circa 3000 BCE
1792
2050-1750 BCE
1936
300 BCE; 1905-1915
1960-1979
1845-1964
700 BCE; 1931
2000-1001 BCE
1791 - 1871
1791
1880-120
1792
circa 1800 BCE
15/7/27
15/7/27
1840-160
circa 3000 BCE
3000 BCE
circa 3000 BCE
circa 3000 BCE
circa 3000 BCE
circa 3000 BCE
1792
1791
1791
circa 3000 BCE
circa 3000 BCE
1791
1910-130
1965-195