
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1760-1775
1775
1775
1752
1770
1750-1760
1755
1762
1762
1769
1757
1761
1752
1762
1762
1761
1762
1762
1762
1762
1767
1760
1755
1750-1760
1765-1775
c.1750
circa 1750
1752
1762
1750
1755
2000-100 BCE
1750
1755
1762
1765
1761
1705-1737
1761
1761
1762
1762
1762
1763
1761
1761
1761
1761
1755