Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1610; 1923
1769
1990-96
1772 (original); 1919 (model)
1763
1705-1737
1761-1762
4000-2001 BCE
2000-100 BCE
1769
1771
1762
1762
1770
1761
1762
1761
1771
1765
1761
1762
1761
1762
1762
1762
1761
1762
1762
1761
1766
1772
1762
1761
1762
1762
1761
1761
1767
1668; 1924
1990-95
1642-1649 (original); 1883 (model)
1765
1762
1770
1764
1936
1600-1500 BCE (original); 1900-1914 (copy)
300 BCE; 1905-1915
6000-5000BCE